[House Hearing, 116 Congress]
[From the U.S. Government Publishing Office]
EVENT HORIZON TELESCOPE:
THE BLACK HOLE SEEN ROUND THE WORLD
=======================================================================
HEARING
BEFORE THE
COMMITTEE ON SCIENCE, SPACE, AND TECHNOLOGY
HOUSE OF REPRESENTATIVES
ONE HUNDRED SIXTEENTH CONGRESS
FIRST SESSION
__________
MAY 16, 2019
__________
Serial No. 116-19
__________
Printed for the use of the Committee on Science, Space, and Technology
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
Available via the World Wide Web: http://science.house.gov
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COMMITTEE ON SCIENCE, SPACE, AND TECHNOLOGY
HON. EDDIE BERNICE JOHNSON, Texas, Chairwoman
ZOE LOFGREN, California FRANK D. LUCAS, Oklahoma,
DANIEL LIPINSKI, Illinois Ranking Member
SUZANNE BONAMICI, Oregon MO BROOKS, Alabama
AMI BERA, California, BILL POSEY, Florida
Vice Chair RANDY WEBER, Texas
CONOR LAMB, Pennsylvania BRIAN BABIN, Texas
LIZZIE FLETCHER, Texas ANDY BIGGS, Arizona
HALEY STEVENS, Michigan ROGER MARSHALL, Kansas
KENDRA HORN, Oklahoma RALPH NORMAN, South Carolina
MIKIE SHERRILL, New Jersey MICHAEL CLOUD, Texas
BRAD SHERMAN, California TROY BALDERSON, Ohio
STEVE COHEN, Tennessee PETE OLSON, Texas
JERRY McNERNEY, California ANTHONY GONZALEZ, Ohio
ED PERLMUTTER, Colorado MICHAEL WALTZ, Florida
PAUL TONKO, New York JIM BAIRD, Indiana
BILL FOSTER, Illinois JAIME HERRERA BEUTLER, Washington
DON BEYER, Virginia JENNIFFER GONZALEZ-COLON, Puerto
CHARLIE CRIST, Florida Rico
SEAN CASTEN, Illinois VACANCY
KATIE HILL, California
BEN McADAMS, Utah
JENNIFER WEXTON, Virginia
C O N T E N T S
May 16, 2019
Page
Hearing Charter.................................................. 2
Opening Statements
Statement by Representative Eddie Bernice Johnson, Chairwoman,
Committee on Science, Space, and Technology, U.S. House of
Representatives................................................ 7
Written statement............................................ 8
Statement by Representative Frank Lucas, Ranking Member,
Committee on Science, Space, and Technology, U.S. House of
Representatives................................................ 8
Written statement............................................ 9
Witnesses:
Dr. France Cordova, Director, National Science Foundation
Oral Statement............................................... 11
Written Statement............................................ 13
Dr. Sheperd Doeleman, Director, Event Horizon Telescope; Center
for Astrophysics - Harvard & Smithsonian
Oral Statement............................................... 21
Written Statement............................................ 23
Dr. Colin Lonsdale, Director, MIT Haystack Observatory
Oral Statement............................................... 28
Written Statement............................................ 30
Dr. Katherine Bouman, Postdoctoral Fellow, Center for
Astrophysics - Harvard & Smithsonian
Oral Statement............................................... 36
Written Statement............................................ 38
Discussion....................................................... 45
Appendix I: Additional Material for the Record
List of authors submitted by Representative Bill Foster,
Committee on Science, Space, and Technology, U.S. House of
Representatives................................................ 76
EVENT HORIZON TELESCOPE:
THE BLACK HOLE SEEN ROUND THE WORLD
----------
THURSDAY, MAY 16, 2019
House of Representatives,
Committee on Science, Space, and Technology,
Washington, D.C.
The Committee met, pursuant to notice, at 10:02 a.m., in
room 2318 of the Rayburn House Office Building, Hon. Eddie
Bernice Johnson [Chairwoman of the Committee] presiding.
[GRAPHICS NOT AVAILABLE IN TIFF FORMAT]
Chairwoman Johnson. Good morning. This hearing will come to
order. And without objection, the Chair is authorized to
declare recess at any time.
We're delighted to see everyone this morning and welcome to
our witnesses. I'm eager to hear more about this exciting
breakthrough. Not long ago, scientists were not sure black
holes were real. Even Einstein had his doubts. Scientists have
since uncovered evidence of black holes, but they had no way to
capture an image until the Event Horizon Telescope.
In science, most knowledge is gained incrementally. From
efforts to peer into the far reaches of the universe, to
experiments conducted at the smallest scale, our collective
understanding of the world around us is built piece by piece.
Each hard-earned discovery brings reality into better focus.
Every once in a while, a discovery will jolt us forward.
Such breakthroughs generate entirely new avenues and tools for
scientific study and a new appreciation for what we can
achieve. The black hole image captured by the Event Horizon
Telescope is both a jolt and the culmination of decades of
incremental advances, most of which were made possible by the
National Science Foundation (NSF).
The dark shadow bounded by a ring of light may look simple
enough, but don't be fooled. The first-ever image of a black
hole is a groundbreaking advancement in science, setting the
stage for a new era of black hole astronomy. This new Earth-
sized telescope also opens up a new window for observation of
other astronomical objects and may further our understanding of
gravity and the evolution of galaxies.
An enormous amount of effort went into clearing the
necessary technological, logistical, political, and scientific
hurdles. While there was never a guarantee that this project
would succeed, the National Science Foundation invested in a
good idea with potentially enormous payoff. This achievement
demonstrates that when the Federal Government invests in our
Nation's best and brightest and in the facilities necessary to
do cutting-edge science, and, importantly, remains committed to
those investments, we are limited only by our imaginations.
I congratulate each of our witnesses and the entire Event
Horizon Telescope team on this astonishing achievement.
Another important part of this story is the international
partnership. This discovery would not have been possible
without contributions from partners around the world, including
from Spain, Chile, Mexico, Europe, Taiwan, China, South Korea,
and Japan. At a time of rising global tensions, let this be a
reminder that the pursuit of science is still a unifying force.
Perhaps the most lasting impact of this discovery will be
the inspiration for students to pursue STEM (science,
technology, engineering, and mathematics) studies. The
excitement of this discovery has no doubt instilled a hunger
that will drive the next generation of scientists to make
discoveries of their own. Today, we celebrate your success. I
look forward to learning more about this incredible image, the
global team that made it possible, and future plans for the
Event Horizon Telescope.
[The prepared statement of Chairwoman Johnson follows:]
Good morning and welcome to today's hearing.
Welcome to our witnesses. I am eager to hear more about
this exciting breakthrough. Not long ago, scientists were not
sure black holes were real. Even Einstein had his doubts.
Scientists have since uncovered evidence of black holes, but
they had no way to capture an image until the Event Horizon
Telescope.
In science, most knowledge is gained incrementally. From
efforts to peer into the far reaches of the universe, to
experiments conducted at the smallest scale, our collective
understanding of the world around us is built piece by piece.
Each hard-earned discovery brings reality into better focus.
Every once in a while, a discovery will jolt us forward. Such
breakthroughs generate entirely new avenues and tools for
scientific study, and a new appreciation for what we can
achieve. The black hole image captured by the Event Horizon
Telescope is both a jolt and the culmination of decades of
incremental advances, most of which were made possible by the
National Science Foundation.
The dark shadow bounded by a ring of light may look simple
enough, but don't be fooled. The first-ever image of a black
hole is a groundbreaking advancement in science, setting the
stage for a new era of black hole astronomy. This new Earth-
sized telescope also opens up a new window for the observation
of other astronomical objects and may further our understanding
of gravity and the evolution of galaxies.
An enormous amount of effort went into clearing the
necessary technological, logistical, political, and scientific
hurdles. While there was never a guarantee that this project
would succeed, the National Science Foundation invested in a
good idea with potentially enormous payoff. This achievement
demonstrates that when the Federal government invests in our
nation's best and brightest, and in the facilities necessary to
do cutting-edge science - and importantly, remains committed to
those investments - we are limited only by our imaginations. I
congratulate each of our witnesses and the entire Event Horizon
Telescope team on this astonishing achievement.
Another important part of this story is the international
partnership. This discovery would not have been possible
without contributions from partners around the world, including
from Spain, Chile, Mexico, Europe, Taiwan, China, South Korea
and Japan. At a time of rising global tensions, let this be a
reminder that the pursuit of science is still a unifying force.
Perhaps the most lasting impact of this discovery will be
the inspiration for students to pursue STEM studies. The
excitement of this discovery has no doubt instilled a hunger
that will drive the next generation of scientists to make
discoveries of their own.
Today we celebrate your success. I look forward to learning
more about this incredible image, the global team that made it
possible, and future plans for the Event Horizon Telescope.
Chairwoman Johnson. I now will recognize Mr. Lucas for his
statement.
Mr. Lucas. Thank you, Chairwoman Johnson, for holding this
hearing, and thank you to all our witnesses for coming to
discuss this incredible discovery.
Since Einstein predicted the existence of black holes,
scientists have been able to observe their effects and refine
theories on how they affect our universe, but this is the first
time we've been able to see a black hole directly, and it marks
a huge milestone in our understanding of the universe.
We have this first-ever image of a black hole thanks to a
pioneering collaboration between observatories around the
world. To detect an image of a black hole we needed a telescope
as big as our entire planet. Not surprisingly, building that
was out of the question. But every challenge presents an
opportunity.
And science funded by the National Science Foundation
joined forces with astronomers, data scientists around the
world to coordinate their observations, in effect, creating a
global telescope. This is a great example of NSF's approach to
basic research and driving scientific progress.
And, as Dr. Cordova told this Committee just last week,
NSF's 10 Big Ideas are about enabling research that crosses
scientific disciplines to make big discoveries. NSF's
coordinated and interdisciplinary approach has already produced
two groundbreaking discoveries in its ``Window on the
Universe,'' first the detection of gravitational waves by LIGO
(Laser Interferometer Gravitational-Wave Observatory) and now
this image of a black hole.
I want to put these achievements in perspective. When
Einstein predicted the existence of gravitational waves, he
also questioned whether these ripples in space-time could ever,
ever be observed on Earth. The signals are so small, traveling
over such an enormous distance, that he doubted whether we
would ever be able to create instruments sensitive enough to
detect them. But now, 100 years later, technology funded by the
NSF, developed over decades, makes it possible for us to
confirm this fundamental prediction.
That matters not only because it helps us understand the
universe in which we live, also because it contributed to the
creation of other technologies that directly affect scientific
progress, including semiconductors that our cellphones and
computers use more powerful.
The NSF's investments in ground-based astronomy have also
given birth to technologies used in everything from airport
security to Lasik eye surgery.
But the scientists these projects have produced may be the
greatest return on our investment. Hundreds of graduate
students worked on this discovery, and their careers will be
informed by this experience. And thousands of young students
who watched this announcement may be inspired to pursue careers
in STEM. These are whole generations of new discoverers that
will contribute to scientific knowledge and American progress.
We don't yet know all the ways in which the Event Horizon
Telescope will broaden our knowledge of the universe or our
technological development here on Earth, but it's certain that
this image is just the beginning of what's to come.
I'm looking forward to learning more about this from our
witnesses, what their discoveries teach us about the universe,
what lessons we can take away from how to coordinate basic
research in the U.S., and what's next for this project.
Thank you for being here, and I yield back the balance of
my time, Chair.
[The prepared statement of Mr. Lucas follows:]
Thank you, Chairwoman Johnson, for holding this hearing and
thank you to all our witnesses for coming to discuss this
incredible discovery.
After Einstein predicted the existence of black holes,
scientists have been able to observe their effects and refine
theories on how they affect our universe.
But this is the first time we've been able to see a black
hole directly, and it marks a huge milestone in our
understanding of the universe.
We have this first-ever image of a black hole thanks to a
pioneering collaboration between observatories around the
world. To detect an image of a black hole we needed a telescope
as big as our entire planet. Not surprisingly, building that
was out of the question.
But every challenge presents an opportunity.
Scientist funded by the National Science Foundation joined
forces with astronomers and data scientists around the world to
coordinate their observations-in effect, making a global
telescope.
This is a great example of how NSF's approach to basic
research is driving scientific progress.
As Dr. Cordova told this Committee just last week, NSF's 10
Big Ideas are about enabling research that crosses scientific
disciplines to make big discoveries.
NSF's coordinated and interdisciplinary approach has
already produced two groundbreaking discoveries in its "Window
on the Universe"-first the detection of gravitational waves by
LIGO and now this image of a black hole.
I want to put these achievements in perspective. When
Einstein predicted the existence of gravitational waves, he
also questioned whether these ripples in space-time could ever
be observed on Earth.
The signals would be so small, traveling over such an
enormous distance, that he doubted whether we would ever be
able to create instruments sensitive enough to detect them.
But 100 years later, technology funded by NSF, developed
over decades, made it possible for us to confirm this
fundamental prediction.
That matters not only because it helps us understand the
universe in which we live, but also because it has contributed
to the creation of other technologies that directly affect
scientific progress-including semiconductors that make our
cellphones and computers more powerful.
NSF's investments in ground-based astronomy have also given
birth to technologies used in everything from airport security
to Lasik eye surgery.
But the scientists these projects have produced may be the
greatest return on our investment. Hundreds of graduate
students worked on this discovery, and their careers will be
informed by this experience. And thousands of young students
who watched this announcement may be inspired to pursue careers
in STEM. These are whole generations of new discoverers that
will contribute to scientific knowledge and American progress.
We don't yet know all the ways in which the Event Horizon
Telescope will broaden our knowledge of the universe or our
technological development here on Earth. But it's certain that
this image is just the beginning of what's to come.
I'm looking forward to hearing more about this from our
witnesses-what this discovery teaches us about our universe,
what lessons we can take away about how to better coordinate
basic research in the U.S., and what's next for this project.
Thank you for being here, and I yield back the balance of
my time.
Chairwoman Johnson. Thank you, Mr. Lucas.
If there are Members who wish to submit additional opening
statements, your statements will be added to the record at this
point.
And at this time, I'll introduce our witnesses. Our first
witness will be Dr. France Cordova. Dr. Cordova was confirmed
as the 14th Director of the National Science Foundation in
2014. She's President Emeritus of Purdue University. I think we
might have some people here on this Committee who might be a
little biased for Purdue--and Chancellor Emeritus of the
University of California at Riverside.
Previously, she was Chief Scientist at the National
Aeronautics and Space Administration. Dr. Cordova also headed
the Department of Astronomy and Astrophysics at Pennsylvania
State University and was Deputy Group Leader in Earth and Space
Sciences at the Los Alamos National Laboratory.
She received her bachelor of arts from Stanford, her
doctorate in physics from California Institute of Technology.
And our next witness is Dr. Sheperd Doeleman. Dr. Doeleman
is Director of the Event Horizon Telescope and an
astrophysicist at the Harvard & Smithsonian Center for
Astrophysics. He's also a Harvard Senior Research Fellow and
project co-leader of the Harvard Black Hole Initiative.
He received his bachelor's of arts degree from Reed College
and his Ph.D. in astrophysics from MIT.
Our third witness is Dr. Colin Lonsdale. Dr. Lonsdale is
the Director of the MIT Haystack Observatory, where he has
worked as a radio astronomer for 32 years. He's been heavily
involved in the development of new techniques and instruments
in radio astronomy, including the VLBI (very-long-baseline
interferometry). He's been involved in the EHT (Event Horizon
Telescope) project from its early days. He also serves on the
governing Board of the international EHT Collaboration, is Vice
Chair and member of the Board Executive Group.
He received his bachelor of science from St. Andrews
University in Scotland and his Ph.D. in radio astronomy from
Nuffield Radio Astronomy Labs in England.
Our final witness is Dr. Katherine Bouman. Dr. Bouman is
currently a postdoctoral fellow at the Harvard & Smithsonian
Center for Astrophysics. In June 2019 she will be starting as
an Assistant Professor in the Computing and Mathematical
Sciences Department at the California Institute of Technology.
As a member of the EHT collaboration, she worked to develop
innovative ways to combine techniques from astronomy and
computer science to construct the first image of a black hole.
She received her BSE from the University of Michigan and
her Ph.D. from MIT.
Our witnesses should know that we will allow each of you 5
minutes for the spoken testimony. Your written testimony will
be included in the record for the hearing. When all of you have
completed your spoken testimony, we will begin questions, and
each Member will have 5 minutes to question the panel. We'll
start with Dr. Cordova.
TESTIMONY OF DR. FRANCE CORDOVA,
DIRECTOR, NATIONAL SCIENCE FOUNDATION
Dr. Cordova. Chairwoman Johnson, Ranking Member Lucas, and
Members of the Committee, thank you for holding this hearing
and for the opportunity to discuss the Event Horizon Telescope,
or EHT, collaboration and the resulting first image of a
supermassive black hole. And thank you for your commitment to
science.
We're excited by this remarkable accomplishment, one that
will transform and enhance our understanding of black holes,
and I'd like to pause for a minute so that we can all in this
room recognize the representatives of the EHT team.
[applause].
I want to focus my remarks today on EHT's history with the
National Science Foundation, the vision and support of so many
dedicated researchers, and what this discovery means for the
future of scientific research. Black holes have captivated the
imaginations of scientists and the public for decades. No
single telescope on Earth has the sharpness to create an image
of a black hole. This team did what all good researchers do;
they innovated. The EHT observation synchronized telescope
facilities around the world to form one huge Earth-sized
telescope.
While this technique, called very long baseline
interferometry, or VLBI, was initially supported by NSF in the
late 1960s. The EHT team took it to a whole new level. They
developed the extraordinary sharpness and sensitivity required
to image a black hole.
Enabled by technology, observations have always advanced
our understanding of the universe, and that is why, for more
than 30 years, NSF has supported technology development for
astronomy through the advanced technologies and instrumentation
program. This program supported EHT with eight separate awards
that got the project started and sustained its early
development. Without this early seed funding, the EHT would not
have succeeded. Thanks to its early support, the EHT project
grew from a small exploratory group to a large international
collaboration.
This discovery would not have been possible without
cooperation and coordination. Such cooperation is exemplified
in the telescope in Chile called ALMA (Atacama Large
Millimeter/submillimeter Array), which was crucial to EHT's
success. While ALMA is a major NSF-supported facility, it's
also supported by international partners.
The success of the EHT also highlights the need for
midscale research infrastructure, one of NSF's 10 Big Ideas.
After more than a decade of development and piecemeal funding,
the EHT was finally reviewed as a whole in our Division of
Astronomical Sciences Mid-scale Innovations Program where EHT
received the funding that enabled these observations. Increased
NSF support of midscale research will enable more effective
support of comparably sized projects in the future.
Supporting basic research has tremendous benefits. As an
example, the methods developed by astronomers in the late 1960s
for measuring positions of distant galaxies had surprising
down-to-Earth benefits. These galaxies served as a reference
for measuring imperceptible changes in the orientation and
rotation of the Earth. Such measurements are now used routinely
to aid modern satellite navigation and the global positioning
system, GPS. Everyone who uses a smartphone to find directions
or search for a nearby restaurant or reserve a rideshare
benefits from astronomy and decades of Federal investment in
such basic research.
In producing the first image of a black hole, the EHT has
generated a global phenomenon. Astronomy is a point of entry
for young people into STEM. This is incredibly important to our
Nation's competitiveness and economic success, as science and
technology are drivers of the economy. Our future prosperity
depends on inspiring the next generation to be curious to learn
and explore, and I'm happy to see lots of next-generation
scientists and engineers in the audience today.
Astronomy is a source of such inspiration. It's just as
important that we continue to support the students and postdocs
as they enter their chosen fields. Their contributions were key
to the success, and this experience will prepare them to reach
even further in the future. This discovery is historic for
astrophysics, it's incredibly meaningful for me personally as
an astrophysicist.
NSF exists to enable scientists and engineers to illuminate
the unknown, to reveal the subtle and complex majesty of our
universe.
Thank you again for your continued support for NSF's
mission and for holding this hearing today and the opportunity
to testify.
[The prepared statement of Dr. Cordova follows:]
[GRAPHICS NOT AVAILABLE IN TIFF FORMAT]
Chairwoman Johnson. Thank you very much. Dr. Doeleman.
TESTIMONY OF DR. SHEPERD DOELEMAN,
DIRECTOR, EVENT HORIZON TELESCOPE,
CENTER FOR ASTROPHYSICS - HARVARD & SMITHSONIAN
Dr. Doeleman. Chairwoman Johnson, Ranking Member Lucas,
Members of the Committee, thank you for the opportunity today
to describe the recent EHT results and their impact.
On April 10, 2019, our collaboration held simultaneous
international press conferences to announce the first image of
a black hole. And as you see--if you did see this image, you
were not alone. On the front page of almost every major
newspaper in the world you could see the bright ring caused by
light bending in the immense gravity of a supermassive black
hole that is 6.5 billion times the mass of our sun. It's
estimated that 4.5 billion people saw these results, all eyes
focused on the same cosmic wonder at the same time.
Why did this result resonate with so many people,
scientists, and the curious public alike? In part it was
because, for over 100 years, black holes have remained one of
the greatest mysteries of modern physics. They are gravity run
amok, a complete collapse of matter into a volume so small that
nothing, not even light, can escape their gravitational pull.
And based on growing evidence, we now believe that
supermassive black holes, with masses of millions or billions
of times our sun's, exist in the centers of all galaxies, where
the hot gas that surrounds them can outshine the combined light
of all the stars in their host galaxy.
This animation shows how light rays from this hot gas are
bent by the black hole, shown here outlined in red. Some light
paths make complete loops around the black hole forming a
bright circular boundary around the event horizon, the point
where gravity traps the light, preventing it from reaching us.
Einstein's equations tell us the precise size and shape of
this ring, so by measuring this feature for the galaxy M87
that's 55 million light-years from Earth, the EHT team has put
Einstein's theories to the most stringent test yet. And this
image, the highest-resolution picture ever taken from the
surface of the Earth, is what we saw. It is confirmation of
Einstein's theory at the edge of a supermassive black hole. It
allows mathematicians, physicists, astronomers the ability to
refine their models of how black holes reprocess matter and
energy on galactic scales.
In fact, the brightening you see at the bottom of this ring
is perfectly consistent with near light speed motions of gas
around the black hole. It also opens a new window on ever more
precise tests of gravity. This is critical because our theory
of gravity is incomplete. We have not yet been able to unify
our understanding of gravity in the quantum world.
To make this image, we developed specialized
instrumentation that link together existing radio facilities,
enabling them to work together as an Earth science telescope.
We reached across borders, included experts from around the
globe, and leveraged billions of dollars of international
resources to deliver extraordinary scientific return on
investment.
Support from the NSF was crucial. Before success of this
project was assured, NSF funding enabled the small U.S. EHT
team to grow and carry out key proof-of-concept experiments. As
confidence in the project grew, we attracted additional
investment from the international science community, which is
why U.S. groups are in leadership positions within the larger
collaboration today.
The EHT collaboration now has over 200 members representing
60 institutes working in over 20 countries and regions. It
truly takes a global team to build a global telescope. And
because the EHT relies on so many technical and theoretical
advances, there are myriad opportunities for early-career
researchers to make fundamental and profound contributions.
Undergraduates, graduate students, postdoctoral fellows, and
junior staff have taken on leadership roles and
responsibilities in areas of high-speed electronics design,
innovative imaging algorithms, and modeling black holes using
national supercomputer facilities. The EHT footprint across
STEM fields is exceptionally broad with rich opportunities for
mentorship.
Building on this success, we are working with our
international partners to enhance the EHT. We aim to move
beyond the still images to making real-time movies of black
holes, enabling entirely new tests of gravity and extreme
astrophysics. We will explore purposefully situating new dishes
to fill out the global virtual telescope and even launch radio
satellites into orbit to realize an EHT that is not bound by
the dimensions of the Earth.
Having worked on the EHT from the earliest stages, I
experienced a deep sense of fulfillment following the result.
But in the end, I personally feel the greatest accomplishment
was assembling an expert and committed team. The look on the
faces of my colleagues when the first M87 images appeared on
computer screens will never leave me. A mix of astonishment,
wonder, pride, awe, and humility. Imaging a black hole for the
first time has inspired our team, and we hope it has inspired
you, too.
Thank you for the opportunity to testify today, and thank
you for your commitment to keeping the U.S. a global science
leader. I look forward to answering any questions you may have.
[The prepared statement of Dr. Doeleman follows:]
[GRAPHICS NOT AVAILABLE IN TIFF FORMAT]
Chairwoman Johnson. Thank you very much.
Dr. Lonsdale.
TESTIMONY OF DR. COLIN LONSDALE,
DIRECTOR, MIT HAYSTACK OBSERVATORY
Dr. Lonsdale. Chairwoman Johnson, Ranking Member Lucas, and
Members of the Committee, thank you for the opportunity to talk
to you about how the Event Horizon Telescope works and how its
truly extraordinary capabilities allowed our team to achieve
the scientific milestone we're recognizing today.
A conventional telescope creates an image by focusing light
from a distant object onto a sensor, much like a digital camera
with a really long telephoto lens attached. Naturally, the
bigger the lens, the more detail that you can see. In fact, if
you can make optically perfect lenses, the magnification you
can get depends only on how big they are.
As Dr. Doeleman has already mentioned, since it's so far
away, the black hole in the galaxy M87 appears extremely tiny
on the sky, so to see it, you need a really big lens with a lot
of magnification. So let's take a more careful look at just how
tiny this black hole is as it appears from the Earth 55 million
light-years away.
And I have a short video here. This is what my observatory
looks like from 25 miles away, and that dome there has a large
radio telescope inside it and down at the bottom right there's
a small figure. That figure is Jason SooHoo, who is one of our
staff members who went to the South Pole actually twice to
support the EHT. And as we continue zooming in and zooming in,
we get down to the level of individual human hairs. And if you
look at an individual human hair under an electron microscope,
it looks like that, and on this, to scale, that is the size of
the black hole image. And just to reiterate, if we zoom all the
way back out, the Event Horizon Telescope can see things much
smaller than a human hair from a distance of 25 miles. So
that's a fairly remarkable amount of magnification.
A conventional optical telescope would need a lens several
miles across to see such a small object, which is impractical,
but the EHT is no conventional telescope. The Event Horizon
Telescope operates with short radio waves, not light, and at
radio wavelengths our lens must be several thousand miles
across, in fact, the size of a planet to get such precision.
The EHT simulates such a lens by combining signals from radio
dishes thousands of miles apart using computational techniques.
Imagine that these radio dishes sit directly in front of an
Earth-sized lens. Radio photons come toward us from the M87
galaxy. Instead of hitting the giant imaginary lens and being
focused onto a sensor, some of them are intercepted by our
dishes. At each dish we capture the photons and record them as
digital data on ordinary computer disk drives. So far so good.
But to make images with our simulated lens, we need a lot of
photons, the more the better. Getting enough photons to image a
black hole simply has not been technically possible until quite
recently.
So how did we do it? Well, first, with strong NSF support,
we have greatly increased the available dish area at key sites
like the ALMA array Chile. And second, we, quote, ``listen''
for photons at many different radio frequencies simultaneously,
generating more digital data. The more digital data, the more
photons. So we record to 128 disk drives in parallel at each
dish site. It's equivalent to simultaneously downloading 11,000
full H.D. movie streams from Netflix. This fills up thousands
of high-capacity disks in one observing campaign, weighing
several tons.
Each campaign involves extensive preparation and logistical
complexity. Talented and dedicated staff from different
institutions travel to some of the most remote and inhospitable
places on Earth like the South Pole, driven by a common goal to
create a unique window into the most extreme environments known
to science.
The effort level and unity of purpose is something I
personally find to be truly inspiring as a tangible
reaffirmation of the spirit of human curiosity that fuels basic
research and the quest for knowledge.
We ship the recorded disks to two locations, my observatory
in Massachusetts and the Max Planck Institute for Radio
Astronomy in Bonn, Germany, where the data streams are combined
in a complex, precise, and computationally intensive process
known as correlation. Now, correlators simulate what a physical
lens does, bringing photons that follow different paths to a
common focal point, synchronized with pinpoint accuracy by
atomic clocks at each observing site. After rigorous quality
checks that can take several months, the correlated data are
released for further analysis.
Because our dishes are few and far between, we can recreate
only small pieces of our imaginary planet-sized lens. Our next
speaker, Dr. Bouman, will talk about how the team has used
innovative new approaches to make a reliable image from
incomplete data.
I want to express my gratitude to the Committee for the
opportunity to speak to you here today, and I'd be pleased to
answer any questions you may have.
[The prepared statement of Dr. Lonsdale follows:]
[GRAPHICS NOT AVAILABLE IN TIFF FORMAT]
Chairwoman Johnson. Thank you very much.
Dr. Bouman.
TESTIMONY OF DR. KATHERINE BOUMAN,
POSTDOCTORAL FELLOW, CENTER FOR ASTROPHYSICS -
HARVARD & SMITHSONIAN
Dr. Bouman. Chairwoman Johnson, Ranking Member Lucas, and
Members of the Committee, it's an honor to be here today. I
thank you for your interest in studying black holes through
imaging and your support of this incredible breakthrough
enabled by the National Science Foundation.
My name is Katie Bouman. I'm currently a postdoctoral
fellow at the Harvard & Smithsonian Center for Astrophysics and
in a few weeks will be starting as an Assistant Professor at
the California Institute of Technology. This morning, I want to
tell you more about the diverse team and imaging methods that
helped make the first picture of a black hole.
The Event Horizon Telescope is an Earth-sized computational
telescope where instruments and algorithms work together to see
something that would be invisible to even the most powerful
conventional telescopes of the future. Unlike a backyard
telescope you may have peered through to study the night sky,
the EHT doesn't capture a picture directly. It collects light
at only a few locations, resulting in gaps of missing
information.
As an analogy, observing the black hole with the EHT a bit
like listening to a song being played on a piano with many
broken keys. Since the EHT only collects sparse measurements,
there are an infinite number of possible images that are
perfectly consistent with the data measured. But just as you
may still be able to recognize a song being played on a broken
piano if there are enough functioning keys, we can design
methods to intelligently fill in the EHT's missing information
to reveal the underlying black hole image.
To construct the image, we develop different imaging
methods based on both established and newer techniques in radio
astronomy. All of these methods require us to specify a
preference toward certain images in order to choose among the
infinite possibilities. And therefore, it was important that we
carefully validate the results.
To assess the reliability of imaging results obtained from
M87 data, we split roughly 40 scientists from around the world
into four teams. Each team worked in isolation, blind to the
others' work, while creating an image of M87. After 7 weeks, we
held a workshop where members from around the globe gathered to
reveal their images to one another. Here, we show the images
that were revealed.
Seeing these images for the first time was truly amazing
and one of my life's happiest memories. This test was hugely
significant. Although each picture looks slightly different, we
found the same asymmetric ring structure no matter what method
or person reconstructed the data. After working for months to
further validate this ring shape, we combined images produced
by various methods to form the image that we showed to the
world on April 10.
No one algorithm or person made this image. It required the
talent of a global team of scientists and years of hard work to
develop not only imaging techniques but also cutting-edge
instrumentation, data processing, and theoretical simulations.
There is a particular group of members I wish to celebrate
today, the early-career collaborators composed of graduate
students, postdocs, and even undergraduates who have devoted
years of work to this project. Early career scientists have
been a driving force behind every aspect of the EHT. By
providing opportunities for young scientists to take on
leadership roles and direct significant work in the project,
the EHT is training the next generation of scientists and
engineers.
So I personally stumbled upon the EHT project as a graduate
student studying at MIT's Computer Science and Artificial
Intelligence Laboratory nearly 6 years ago and immediately fell
in love. Like many big science projects, the EHT had a need for
interdisciplinary expertise, and taking an image of a black
hole shared striking similarities with problems I had
encountered earlier in my studies such as capturing a picture
of your brain from limited data using an MRI scanner.
Thus, although I had no background in astrophysics, I hoped
that I could contribute from my area of expertise in advancing
the EHT technology. If it wasn't for the help of the National
Science Foundation Graduate Fellowship which gave me the
freedom to work on risky projects, I may have never had the
chance to be part of this incredible endeavor.
The EHT introduced me to an entirely new domain where
emerging computational methods were essential to the success of
scientific goals. Moving forward, the computational imaging
tools that we developed to study black holes could help improve
technologies of the future.
My story is just one of many. I'm one of the numerous
early-career scientists who have devoted years of their lives
to making this picture a reality. However, like black holes,
many early-career scientists with significant contributions
often go unseen. Although the EHT has been a remarkable success
story, we must not forget the contributions of all these young
scientists whose names might not make it into the newspapers,
for only with them and the diverse group of astronomers,
physicists, mathematicians, and engineers from all around the
globe have we been able to achieve something once thought
impossible, taking the first image of a black hole.
Thank you for the opportunity to testify and for your
support of groundbreaking, collaborative, and interdisciplinary
science.
[The prepared statement of Dr. Bouman follows:]
[GRAPHICS NOT AVAILABLE IN TIFF FORMAT]
Chairwoman Johnson. Thank you very much.
At this point we'll begin our first round of questions, and
the Chair recognizes herself for 5 minutes.
And this question goes to all. NSF made a significant
commitment to this project without any guarantee that it would
succeed. In a time with many competing financial priorities,
why is it important that the Federal science agencies take
risks like this for basic research even if there's no
foreseeable application?
Dr. Cordova. Sure, I'll start. Thank you very much for the
question, Madam Chairwoman.
The definition of NSF is to take risks in science and
engineering, risks that have potentially very high rewards. We
saw an example of this with the first detection of
gravitational waves on Earth a few years ago, and subsequently,
a project that we invested in starting 40 years ago has just
yielded tremendous results, most recently, many more detections
of gravitational waves in the third run of LIGO.
And then just a short while ago we announced really a
solution to the enduring mystery for over 100 years of the
origin of cosmic rays, with the detection of neutrinos and
high-energy gamma rays using our South Pole telescope and many
other telescopes on Earth and in space.
Doing this kind of observation--and the discoveries--is
really what NSF is about. We like to say that NSF is where
discoveries and discoverers, as you heard from Dr. Bouman,
begin.
In my testimony, I mentioned that GPS, and in previous
testimonies MRI, companies like Google and Symantec, Qualcomm,
all of these are benefits of investing in basic research. It
just has--sometimes we can have benefits that happen
immediately, and sometimes it takes a very long time to realize
benefits. But the upside is that they are truly outstanding
miracles that happen when we invest in basic research.
Dr. Doeleman. Could I add to that, Chairwoman Johnson? I'd
also add that the risks taken by the National Science
Foundation for basic science are really critical, that with
basic science, you don't always know where you're going to go,
where you're going to wind up, but by addressing the deepest
mysteries in the universe, black holes, with the best
technologies that we have, we have a chance to answer the
deepest fundamental questions about our universe.
If you had asked Einstein, you know, what ramifications his
theory of general relativity would have had when he came up
with it, he would have had no answer, right? We would've said
with our cell phones we can now locate ourselves to within
pinpoint accuracy on the globe, and he would have looked at you
and said what's a phone, right? He wouldn't have had any idea
really to even understand the question. That's how long it
takes sometimes for the fruits of basic research to be
realized. But when you ask those basic questions, they almost
always pay off.
Dr. Lonsdale. So I'd like to add something. I think that
when the NSF invests in something speculative and high risk
like this and it pays off, as it has in this case, it is a real
attention-grabber not just for all the scientists who are
interested in doing this but the whole world. We heard Dr.
Doeleman say that 4.5 billion people around the planet saw
this. And this is the way that young people can be inspired to
think about, you know, emulating some of this work and getting
involved in the STEM disciplines, so it is an important
component of feeding the STEM pipeline.
Dr. Bouman. Yes, I agree with everything that has been said
by my colleagues here. I think technology and basic science,
you know, really drive each other. They feed off each other and
they help each other grow. And so it's important that we
continue to invest in basic science because we don't
necessarily know the ramifications of how that will manifest in
technology of the future. Lots of the techniques that we've
developed for imaging black holes can be adopted potentially in
the future for other applications that we might not have even
thought of now.
And another thing is I do want to emphasize Dr. Lonsdale's
point as well in that I think that this picture has really
captured the imaginations of a generation of new young
scientists, and I've even had, you know, 4-year-old girls come
up to me and tell me about the black hole, and I think that
getting that interest in science to young students at a young
age, it will help them enter the STEM fields and make
contributions to many different projects.
Chairwoman Johnson. Thank you very much. I'm not out of
questions, but I'm out of time.
Mr. Baird?
Mr. Baird. Thank you, Madam Chair. And to all the
witnesses, we really appreciate your testimony and the
discoveries you're sharing with us today.
I would also like to congratulate all of you on receiving
the Diamond Achievement Award this week at the National Science
Foundation awards gala, so I commend you for that.
Dr. Bouman, I have a question that relates to the
importance of the opportunity you had to do research at such a
young age and a career as a scientist. I think you conducted
some imaging research at Purdue University while you were still
in high school. So would you care to elaborate on that?
Dr. Bouman. Sure. So I actually was--got a job at a lab
in--at Purdue University when I was--in the summer after 11th
grade partly because I had kind of stumbled upon a class taking
a computer science class in high school, which I had never
really thought about taking but I took on a whim and, because
of that, I had an interest from--because I understood this new
language of computing, a professor there, Professor Edward
Delp, invited me to help his graduate students in the lab there
that summer. And that was the first time I had exposure to real
research, to imaging and the--kind of the exciting world of
imaging.
And one thing that really grabbed me from that was being
able to see the results. And I really loved being able to work
on problems where you can visualize your results. And so from
that I kind of gained a love of imaging and images, and that
drove me in my future--my path toward studying electrical
engineering and computer science, computer vision, and
eventually being on the Event Horizon Telescope project. So I
think that spark of passion at a young age really brought me to
where I am now, so I'm eternally grateful to my opportunities
at Purdue for that.
Mr. Baird. Thank you. My next question, maybe all of you
might want to respond, but it's in keeping with the theme that
you had for the National Science Foundation award. Do you have
any recommendations on how we might ignite the spark that
stimulated you to get into your profession so that we can keep
these students encouraged and excited and fulfilling that
pipeline to have more researchers in the future?
Dr. Cordova, do you want to start with that?
Dr. Cordova. Sure. Well, my own STEM spark was from
watching a television show ages ago about neutron stars when
they were first hypothesized as being responsible for certain
phenomena that were being observed. And one of the MIT
professors on the show talked about the energy that would be
liberated if you dropped a marshmallow onto a neutron star. And
I was so mesmerized by that concept.
The next day--I was actually doing an education project in
Cambridge, Massachusetts--I took a bus and went right down to
MIT to meet that professor, and I said this is what I want to
do for the rest of my life. I want to work on this. And so for
some reason they gave me a job for the summer, and it all
worked out. So I really believe that you can have your
inspiration from so many different places.
And what NSF is trying to do is find curriculum projects
that happen in schools, like computer science in the classroom,
and to help wonderful teachers get more skills. But we also
spend part of our portfolio, as I think you know, on informal
science education, such as money to museums and to television
shows about science. There has to be a myriad of ways of
reaching out and trying to inspire people to know more about
science and be attracted to it.
Dr. Doeleman. It's a wonderful question, and it's one that
we really focused on in the project. I think you've seen that
this image and the pins you have in front of you are--really
resonate with the public and scientists alike. It's a real
opportunity to get people at a young age, which is really when
you want to ignite that spark into science. Mine came about
with a stint at a museum that I worked at actually looking over
animals, so I got into this through biology if you can possibly
believe that, so you never know where the spark is going to
ignite.
But getting the outreach is really important for this. It's
really important to get into museums, informal outreach, and
also to invite the young people into labs in places where they
can really do research.
Mr. Baird. I'm out of time, but the Chairwoman has allowed
me to go ahead and let the other two finish.
Dr. Lonsdale. Thank you very much. Yes. Well, my own spark
was at a very early age also, which seems to be a bit of a
consistent theme. I was looking up at the night sky when I was
5 years old and had a hunger to read all about it, and my
parents got me a telescope when I was 8. And also at the same
time the U.S. space program was taking off quite literally, and
that--all of this was completely mesmerizing to me, and it set
me on a course for life to pursue this type of work.
And I see that in very tangible ways in what I'm doing now.
My observatory, we have a fair amount of public outreach, and
one form this takes, for example, is open houses. And just
recently I held an open house where I was, for the first time,
able to talk about the black hole result, and the children in
the audience were by far--they were absolutely thrilled to
pieces. And I got lots of questions afterwards. But the longest
time and the most questions came from a 10-year-old.
And I think that connecting the scientists who have the
enthusiasm for the work with the young people, you know, like
10-year-olds who are--who have minds that are sponges for
information, that is incredibly potent. And that's been my
experience throughout my work in public outreach.
Dr. Bouman. Yes, so I would say, you know, throughout my
early years I had many different sparks, and I think having
many opportunities to continue to grow that interest in science
is so important, to have many different programs and
opportunities.
However, I will--I want to highlight one that I had in
sixth grade. My science teacher had us all enter the science
fair, and I--this was the first time where I really did a
science project that was outside of just your standard homework
that you do, and I thought for ages about what I would work on.
And I decided to work on how--what makes the best bread. So I
actually baked probably hundreds of loaves of bread with
different amounts of salt, different amounts of sugar, and
different types of yeast, and I measured how big they rose and
the taste. I even filled out IRB forms to have my friends taste
the different bread. And that was a really fun experience, a
wonderful experience. I entered it into the science fair in the
area and won gold in my category. And that I think was my first
true excitement where I knew research was a pathway for me.
Mr. Baird. Thank you, and I yield back.
Chairwoman Johnson. Thank you very much.
Ms. Bonamici?
Ms. Bonamici. Thank you very much, Chair Johnson and
Ranking Member Lucas. And thank you to all of our witnesses.
I also want to congratulate the National Science Foundation
and the entire team around the world for this groundbreaking
work on the Event Horizon Telescope project. Congratulations.
Not only was this an incredible scientific achievement, the
release of the first-ever image was of course--sort of
shattered the glass ceiling for women in STEM, so it was a
pretty significant day. I remember when the news hit, and it
was an inspiring moment of course for young women who want to
go work in what are still traditionally male-dominated fields
in the sciences. This certainly demonstrates the value of
teamwork and collaboration in scientific discoveries.
Dr. Bouman, I'm the Founder and Co-Chair of the STEAM
caucus, where we advocate for integrating arts and design into
STEM learning to spark creativity, to get more people involved,
and to really have that well-rounded education that stimulates
both halves of the brain. I appreciated the analogy in your
testimony comparing the observations from the telescope to a
song on a piano with broken keys. There is some research that
shows the Nobel Laureates in the sciences are more inclined to
be engaged in arts and crafts than other scientists, so it's
just a little story there.
So why was it important to have an interdisciplinary team
to develop the imaging algorithms, and what did you learn from
the development of the algorithms that could benefit future
unexpected observations going forward?
Dr. Bouman. Yes, so the EHT, like many big science
projects, really draws on many different areas. So, you know,
at its core it's a science project. We're trying to learn about
black holes, and there, we need theorists to tell us, you know,
what do we expect? But also it's an engineering project. You
know, we spent over a decade building a telescope with new
instrumentation that had to be put together, and because it is
a computational telescope, we also had to develop algorithms
and methods, and this requires us to understand computation and
optimization and many different--kind of how do all these
pieces play together and come together to give us this kind of
amazing result, so we really had to have, you know,
instrumentation, algorithms, theory. But it was really all--
each part was essential.
And you also have to understand each part as a--you know,
when I started this project actually, as I said, I came from a
computer science kind of area, and I--you know, I met with Dr.
Doeleman and I was like, oh, this is such an exciting project.
And I kind of--I decided, oh, I really want to work on it, but
I kind of went off on my own and started to try to read about
the ideas of interferometry and how to make an image and, you
know, coded up some little simple algorithm, but I really--you
know, that doesn't get you anywhere just being by yourself. I
didn't understand the intricacies of the data. What kind of
challenges do we have with this data?
And so it was really essential when it really started--when
we really started being able to push the algorithms is when we
all kind of got together from different parts of the team,
understood what kind of noise do we see in our data, what is
really different about the data and challenging about the data.
Even time that I spent at a telescope at over 15,000 feet above
sea level I learned where does--where do things go wrong, and
how do we account for this in our algorithms?
And so I think it was really essential even on just one--
you know, making an imaging algorithm, which is just one part
of this huge project, even combined information from across the
project.
Ms. Bonamici. Wonderful. Your enthusiasm is amazing. I hope
it's contagious. I want to get a question into Dr. Doeleman,
who I learned is an Oregonian.
And, Dr. Doeleman, you told me about some of your early
days with all the hands-on learning at the Oregon Museum of
Science and Industry, which is a gem in the Pacific Northwest,
and I know gets a lot of children and adults engaged in
science.
You noted that capturing an image of a black hole was
presumed to be impossible just a generation ago but now can
lead to the emergence of a totally new field of science. So how
can black holes be used as tests of our universal theories and
what further resources are needed to succeed in the EHT's next
scientific feat?
Dr. Doeleman. Thank you for the question. There are a lot
of different ways to proceed from here. This really is the tip
of the iceberg. Imagine when Galileo was looking through the
first telescope. It wasn't the end of astronomy, it was the
beginning of astronomy. In the same way, this image you see
here is creating the ability for us to use the most intense
cosmic laboratory as a way to understand the universe.
Normally, you would have to build a supercollider or something
like that to attain the energies and the extreme physics to
probe the unknown. Here, we're using the edge of a black hole
that nature presents us as a natural laboratory.
So in the future, we want to make movies, not just still
images, because what you're seeing here is light orbiting
around the black hole. That's one test of Einstein. Now, we can
move to matter orbiting around the black hole, make movies of
this, a completely different test of Einstein, testing the
period it takes for matter to orbit around. And more than that,
we can see how these black holes are ferocious engines at the
centers of galaxies launching these jets that can pierce an
entire galaxy and disrupt star formation.
So black holes are at the heart of why the night sky looks
the way it does. And, as we move forward, we'd like to fill in
this virtual telescope with putting new telescopes tailor-made
to fill out that virtual Earth-sized array, and that will
sharpen our focus and let us make movies.
Ms. Bonamici. Fascinating. My time is expired, but be
assured we will be following the work. It's wonderful. Thank
you. I yield back.
Chairwoman Johnson. Thank you. Mr. Biggs.
Mr. Biggs. Thank you, Madam Chair, and thank you, Ranking
Member Lucas. And thank you to each member of the panel for
being here today. I appreciate you sharing your experience and
sharing with us this important discovery and how you went about
it. And I think many of us are very excited to see what the
next step is going to be.
I would be remiss, however, if I didn't mention the
contributions of the university in my home State, University of
Arizona, where the submillimeter telescope on Mount Graham was
used and coming up for the 2020 series will be the Kitt Peak
Observatory will also be joining, and I'm excited about that.
So having made a commercial now for my own State
University, I will now go to my questions. Dr. Doeleman and Dr.
Lonsdale, when the news broke that the first image of a black
hole was going to be released, many of us thought it might be
Sagittarius A*, the supermassive black hole at the center of
the Milky Way. What have been the challenges for imaging that
black hole, and do you expect to be able to produce an image of
that particular black hole?
Dr. Doeleman. It's a wonderful question. We have two
primary targets in the Event Horizon Telescope project, both of
which we--for both of which we can resolve that event horizon.
We focused on M87 because the results started falling out very
cleanly in a very pure way at the get-go, so we oriented all of
the efforts of the collaboration toward that goal to get our
first results out. But Sagittarius A* is next on our list.
It is a little bit more difficult because, during the
course of one evening of observing where we fill out the
virtual lens because the Earth rotates and changes our points
of view of the object during the night of observing, the source
itself is changing because it is 1,000 times smaller in mass
and therefore it's 1,000 times faster in evolution than M87.
During one night of observing, M87 stays static, but
Sagittarius A* evolves in front of our eyes so to speak. So
we're developing some new algorithms, courtesy of Katie and the
other early-career scientists, to handle that.
Dr. Lonsdale. And I can speak a little bit to the ways that
we might be able to enhance the Event Horizon Telescope. And,
I'm sorry, thank you very much for the question. It is right on
point for some of the things that we're thinking about for the
future.
One of the things that Dr. Doeleman has already mentioned
is adding additional telescopes to the array, and what this
does is create more points in front of that giant imaginary
lens to collect information. And, as it turns out, if you
double the number of telescopes, you actually quadruple the
amount of information that's available to reconstruct the
images.
So because Sagittarius A* is changing quickly, we need to
gather a lot of information in a shorter amount of time so that
it doesn't change too much. There's a couple of ways to do
that. One is to add telescopes. Another, which is perhaps a
little further into the future, is to put dishes into low-Earth
orbit because those move much more quickly than the Earth
rotates and sample more data more quickly. So we've got a
couple of ways to improve the potential for imaging and making
movies of Sagittarius A*.
Mr. Biggs. Yes. I'm looking forward to that. Dr. Bouman,
what other applications can come from the computational, and
you had kind of touched on this, but I want to know what other
applications you think might develop from computational imaging
tools that were developed to study black holes.
Dr. Bouman. Sure. If we're on the topic of Sagittarius A*
and how it's evolving really quickly where you have this huge
amount of evolution over the course of the night, this causes
challenges from us from an imaging perspective because the
measurements that we take are taken over the course of a night,
so each measurement is basically from a different snapshot of
the black hole. And so we're coming up with ways of tying this
information together to make not just pictures of black holes
but movies of it evolving over the course of a night.
And this kind of similar--this kind of approach could be
applied to many different problems. So, for instance, one that
has I think a very similar problem is an MRI. When you're
studying, for instance, organs that are moving or even like a
fetal MRI, taking images of a baby inside of a mother's womb--
and because, as the MRI machine scans, the baby is moving, you
actually also have to have kind of a model of motion and
understand that the picture is also evolving. So techniques
that we use for imaging a black hole, similar ones could be
applied to this idea of how do we image a baby inside of a
mother to get a better diagnosis of issues that might happen?
Mr. Biggs. Great, thank you. I still have time. I'm going
to zip through this question real quick. This project is a
great example of international collaboration and science, and
questions are these. What makes a successful S&T international
cooperation agreement, and how do we ensure these agreements
are two-way streets and not the U.S. feeding its knowledge and
talents to other countries without reciprocation? So whoever
wants to take those two questions.
Dr. Cordova. Yes, I'll start. We have a lot of
international collaborations on our various facilities. A great
example is the ALMA telescope that played such a big role in
this observation. Also, we are contributors to the Large Hadron
Collider at the CERN in Europe, and many, many of our biggest
projects have international collaborators because the talent is
worldwide, and also they help with the funding of course.
And so we have those principles for international
collaboration, but it has to be a win-win situation, as you
said, Congressman. Everybody has to gain from this, everybody
has to contribute scientific talent and get something from it.
And the collaborations have to do something really important
that's going to move the discovery needle forward. Shep?
Dr. Doeleman. It's a great question. We wrestle with that,
and we were successful because we adhered to some principles as
we put together this collaboration. One was transparency. You
have to make sure that you know what everybody is doing at all
times. And we ensured that by making sure that all the working
groups that we put together had members from all the different
constituencies so everybody can see actively what's going on.
We didn't sequester one group here to work on one thing or
one group here to work on something else. We really combined
everything through the miracle or burden of videoconferencing.
We tend to live our lives on video cons these days, but it's
really true that you can publish with someone now that you've
never met. And it's kind of an uplifting way to think about
things, right? I mean, we can really broaden the team across
borders and across cultures and across different practices in
this way.
And we also had very strong policies on publication and how
to proceed with allocation of resources and planning for the
next arrays and how we're going to go to the next generation.
So by being very inclusive, we got the best of everyone, and we
also made sure that everyone saw what we were doing. And that
is one of the principles that I think has made us successful.
Chairwoman Johnson. Thank you very much. Mr. Lamb.
Mr. Lamb. Thank you, Madam Chairwoman.
This is a question for anyone that's knowledgeable about
it, but I was curious about the supply chain for the
construction of the telescopes themselves, both the current
ones that we have and the additional ones that may be coming.
Are we relying on a lot of American businesses and American
materials for these things? And I would ask the same thing
about the software and computers that we're using for the
imaging as well. So if anyone is able to address that, thank
you.
Dr. Cordova. This particular project was completely reliant
on telescopes that already existed all over the world,
obviously on many continents. Their supply chains are all
different. In the case of U.S. telescopes, of course, we try to
do our best to use American-made products. We have a few
telescopes that were used in Arizona and Hawaii, and we
anticipate more of those. But this is really all about a global
supply chain.
Dr. Doeleman. Yes, thank you for the question. I would add
that while we all work together, all the constituencies within
the project realize that they want to use local resources where
possible, so we lever that. So Europe uses the best
construction practices and companies in Europe, but we use the
best construction practices and companies here in the United
States. We define what the instrumentation has to do, and then
we apportion who's going to do what based on the local
resources. So we've been very careful to lever U.S. businesses
when we can.
And I just want to give a shout-out to Arizona again that
the submillimeter telescope on Mount Graham was involved in the
very first observations that we ever made of Sagittarius A*
that got this whole thing started, and it was the investment of
the NSF in that U.S. site that really made that possible.
Mr. Lamb. Thank you. Is--are there particular companies in
the American telescopes that have been leaders or been
especially reliable for us in the construction of these things
or that we might be looking to going forward?
Dr. Doeleman. Do you want----
Dr. Cordova. You may have particular examples, but we can
certainly, Congressman, get together a list of that and give it
to you. They are many and complex.
I do know that at our own universities, amazing work is
going on by investigators that we fund to build a lot of
telescope optics, so that's a great credit to the way the
science engine works.
Dr. Doeleman. Actually, if I may, a very interesting tie-in
here is that the size of the telescope you need depends on the
bandwidth, as Dr. Lonsdale was describing. So by investing in
high-speed electronics, for which we use, you know, like
Xilinx, for example, which is a U.S. company to do the
throughput on our field-programmable gate arrays get a little
bit wonky, that decreases our reliance on steel necessarily, so
we don't need to build huge telescopes. We can collect more
data by recording bigger slices of the radio spectrum and make
the dishes smaller. That changes the kind of company you go to
or the kind of designs you do, so it's very interrelated. And
it's a very interesting optimization problem, and that's what
we're working on now.
Mr. Lamb. Thank you. Madam Chairwoman, I yield back.
Chairwoman Johnson. Thank you very much.
Miss Gonzalez-Colon.
Miss Gonzalez-Colon. Thank you, Madam Chair, for holding
this hearing and for all of us that are here today, I think
this is a remarkable event and achievement. I want to
congratulate everybody involved in this.
Dr. Doeleman, from what I understand in reading your
statement, the project is looking to expand by including three
new additional telescopes. Do we identify where those
telescopes are going to be included from, any country that
you're working right now in that regard that you can share with
us?
Dr. Doeleman. So we're looking broadly at how to fill in
this Earth-sized virtual lens. So in the next year we'll be
including a new telescope in France, NOEMA, which is an array
in the French Alps, and that's already very--underway. The Kitt
Peak Telescope that the Congressman mentioned will be lighting
up on the Kitt Peak National Observatory. That's another one.
And beyond that, we're looking primarily at potential new sites
where we'd like to put new telescopes, and for that, we're
doing some optimization studies now. In fact, we're putting a
proposal in soon for that, which will lead to a global design
for where we want to put the next site.
So it's very interesting, when you look at this image and
you say, well, how can we make it better, there are metrics,
right? You can say, well, it can be sharper, it can be more
sensitive, and so where you put the telescopes affect those
metrics. They affect how much better the image would look. And
you can make what we call a heat map. You can look on the whole
globe and find out where you need to put the next telescope to
maximize the scientific return from this image. And so we're
looking at that now trying to find out where we want to put
them. And then we think we can put modest dishes, smaller
dishes at these new locations to build out the full array.
Miss Gonzalez-Colon. So that's the process to select the
telescope and the places they're going to be installed?
Dr. Doeleman. That's what would like to do, yes.
Miss Gonzalez-Colon. OK. And what are going to be the main
challenges for you in that process of selecting which
telescopes and where those telescopes are going to be
installed?
Dr. Doeleman. Well--what's that?
Dr. Cordova. Getting funding.
Dr. Doeleman. Yes, getting funding. I'm told by Director
Cordova that getting funding is very important.
Miss Gonzalez-Colon. Very clever.
Dr. Doeleman. And it is. But the first part is design
really. It's coming up with the new algorithms, the new metrics
of the stuff that Dr. Bouman was talking about and the new
electronics that Dr. Lonsdale was talking about. Folding that
all into the equation and finding out where we can get the best
value for the taxpayer's dollar, where can we target these--the
locations of our next dishes to ensure that for the best return
on investment that we can get that.
Miss Gonzalez-Colon. The increase in cost, of course, by
installing those new telescopes will mean that you need to plan
ahead. Are we willing to look in the private sector investment
to help out in this endeavor?
Dr. Doeleman. Well, that's a wonderful question. You know,
it turns out that when you get a result like this, others want
to invest in it, too, so we are currently--we currently have an
NSF award for which Google is partnering with us to help us
move some of the computation that we do because it is very
computational-intensive, as Dr. Bouman said, to the cloud where
we have virtually unlimited processing power, for example, the
same thing with some of the high-speed digital electronics. So
we're working in that--definitely in that direction.
Miss Gonzalez-Colon. Dr. Bouman, I read in your statement
as well that you mentioned that, given the limited number of
telescopes and limited number of locations, there are
information gaps. From what I understand, it's looking of
course to increase the cooperation of those other countries.
The Director just explained the process for the new challenges.
Can you tell us about what we're expecting to see in using
those new telescopes?
Dr. Bouman. So we aren't just observing M87 once. It's not
like we observed it and then we go away and we look at other
things. We're going to continue to every year go back, improve
our instrument, and try to learn more and more. So--and look at
other sources like Sagittarius A*.
So when--we are simultaneously improving the instrument and
our algorithms to work together to answer these questions, and
I think that now that we have a first image and see that it is
possible to see this ring, then we can go back and say, OK,
here--where is our missing information? Where--and we can
target those areas through new instrumentation and algorithms
and try to answer those questions and get a clearer picture of
GR and light--general relativity and how it acts around a black
hole. So I think that is something that we look forward in the
future to seeing.
Miss Gonzalez-Colon. Thank you, Doctor.
And thank you, Madam Chair. I know my time is expired, but
I know that the broader implications of this discovery will
help a lot of areas between physics and data science. I yield
back.
Chairwoman Johnson. Thank you very much. Mr. Casten.
Mr. Casten. Thank you, Madam Chair. Thank you to all the
panelists. I got to tell you, you guys should take this show on
the road. Your enthusiasm is just so infectious and it's so
cool.
The--so I learned a valuable lesson--I hope not to repeat
last week, which is that if you miss an episode of Game of
Thrones, you find out a couple days later that apparently it
all ends with dragons. I don't want to do that again, so can
you give us a little hint of what--you mentioned that we--
you're going to be able to now tune this on the black hole at
the center of the Milky Way. When should we be tuning in for
that?
Dr. Doeleman. OK. Well, as they say, I would tell you,
but--well, so, first of all, let me say that, bound by a common
science vision, it really helps when you want to prevent a
leak. So what really surprised people with this result is that
people thought it was going to be on Sag A*, and we had 200
people from around the globe and nobody broke the code, right?
Nobody broke the silence, and I think it's because we all
understood the impact that it would have, and we wanted to be
able to tell our story, the scientific story after peer-
reviewed publication of our results, so that was a key part of
it.
And as we go forward and look to Sag A*, of which we'll be
using the algorithms and new computational platforms, we're
going to be attacking that with the same rigor and the same
crosschecking, the same purposeful tension within the
collaboration that allowed us to produce this result. So we'll
be splitting up into teams probably, as Dr. Bouman described,
we'll be crosschecking, double-checking, making sure that one
frequency gives us the same image as a different frequency, one
polarization gives us the same image as the other polarization.
We'll check everything, and only after that will we reveal in
an episode of Game of Thrones----
Mr. Casten. I will take that as a constructive nonresponse,
and I'll not pressure.
Dr. Doeleman. I would estimate within a year.
Mr. Casten. Well, part of why I'm intrigued is that, you
know, you've talked about that you can--there are sort of tests
of Einstein's relativity in this, that you'll have--be able to
do other questions, and in this whole idea of like actually
seeing a movie of this. And I guess I'd just love to hear your
thoughts about what are the types of questions that we can
answer once you tune it there both in terms of looking at the
Milky Way and in terms of potentially getting some--you know,
some movement? What types of questions are you going to be
asking--be able to learn at that point that we don't know now?
Dr. Lonsdale. Well, the black hole at the center of our
galaxy, Sagittarius A*, may look different from what you see on
the screen there in a few different ways. The black hole at the
center of the Milky Way is in a different environment. It's
accreting material at a very low rate. It may be oriented on
the sky in a different way. And so there's a lot to learn by
looking at different black holes. We don't know what we'll
find. It's one of those things where it's right at the frontier
of what we're technically able to do, so it places a tremendous
emphasis on checking and double-checking, as Dr. Doeleman said,
to make absolutely sure that we know not only what the image is
but what the uncertainties on the image are. So we're going to
be working hard on that.
Mr. Casten. So if I understand, you've got a couple more
telescopes that you're adding. You've got one that you added in
2018 and then two more in 2020 if I've got that right.
Dr. Lonsdale. Yes.
Dr. Doeleman. Well, we're adding two more next year for the
observing campaign in 2020, and then we're looking to the
future to add even more than that.
Mr. Casten. OK. So what sorts of things are you going to be
able to see once you have those additional data inputs? And I'd
love to know from Dr. Bouman, like as you think about sort of
analytically, what holes in your data field if you will are
going to be filled in with those additional--you know, what are
you sort of salivating to see once you get those additional
points?
Dr. Bouman. Yes, so I think, you know, one thing is we
don't know what we're going to see, so that I think is part of
the mystery and excitement of it all. But one thing is if we
zoom in toward Sagittarius A*, all of this variability that
hopefully, by adding new telescopes, we will get a better grasp
of, we can better map out the space-time around a black hole.
So, right now, you know, we just have a static picture. But
just like seeing a movie tells you so much about--more about
your environment than just a single picture, getting that movie
will allow us to learn so much more about the black hole. For
instance, the black hole in M87, we get an estimate of its
mass, the size it is, but by seeing this evolution around a
black hole, maybe we can learn about not just its mass but its
spin, and knowing both the mass and the spin tells us about how
it should affect every--the space-time around it. And so I
think that being able to have a grasp on that will teach us a
lot.
Mr. Casten. Well, this is very cool. I yield back. Thank
you.
Chairwoman Johnson. Thank you. Dr. Babin.
Mr. Babin. Yes, ma'am, thank you, Madam Chair. And thank
you all for being here.
Dr. Cordova, I enjoyed you accompanying our Committee. I
guess it's been the year before last when we went to the Arctic
and saw some neat things. Good to see you again.
I wanted to ask a question about return on investment, and
I'd like to hear it from maybe all of you if you get a chance.
We'll start with Dr. Cordova. Our constituents may ask why
invest taxpayer funding in imaging a black hole? And that is
what can you tell them or what can we tell them has been the
return on their investment? And I liked what Dr.--is it Bouman
or Bouman?
Dr. Bouman. I don't mind either, but Bouman is what I
usually say.
Mr. Babin. All right. Bouman. See, we don't know what we
don't know, so that's kind of a mysterious thing to say, but
you know, if we can ever get the James Webb Space Telescope up
there, I assume that's going to open up some new windows and
horizons for us as well.
But let's start with you, Dr. Cordova, on return on
investment where somebody says, what are we getting for
spending all this money on imaging a black hole?
Dr. Cordova. Well, there's three ways I like to answer
that, but I want to give a lot of time to my colleagues here,
so I'll just say the three words are inspiration----
Mr. Babin. Right.
Dr. Cordova [continuing]. And that is--that's at the root
of who we are as human beings, and that's what draws us in to
our fields where our passion and our commitment is. And we all
were sharing earlier our STEM spark, and so it's so important
with young people to get them inspired, so we had great moments
like landing on the moon and the discovery of the Higgs boson
and this imaging of the black hole, and who knows how many
people that will attract into science, all kinds of science and
engineering.
Mr. Babin. Right.
Dr. Cordova. The second one has to do with all the
engineering and computational tools that go into a discovery
like this, a challenge like this. It took them over a decade to
do this, and, as you know, the LIGO gravitational wave
experiment took 40 years.
And the amazing amount of engineering prowess and
computational prowess that it takes in order to make those
kinds of feats have many, many spinoffs. There are many things
that are invented for the first time that then go into
spinoffs.
And the third one is that when we invest in truly
fundamental basic research, it can have enormous benefits, not
just little incremental benefits. We talked earlier about GPS,
about MRI technology, about new companies that are invented
like Google itself. These start at the root with just a little
piece of fundamental research.
Even the people who are discovering--we funded Charlie
Townes, the Nobel Prize winner, we gave him 17 grants over his
lifetime, and he never said I thought it would end up in the
maser--and we use masers for the clocks in order to synchronize
the telescopes--he never thought it would end up in the laser
and doing eye surgery and all. But he did it because he was
driven toward a fundamental discovery.
Mr. Babin. Right.
Dr. Cordova. These have amazing benefits for the public but
sometimes a little later on.
Mr. Babin. The quest for knowledge and curiosity, that's
quite----
Dr. Cordova. Yes.
Mr. Babin. Dr.--is it Doeleman?
Dr. Doeleman. Doeleman.
Mr. Babin. Doeleman.
Dr. Doeleman. I answer to many things. So when I talk to
the team about what we're doing, I often use the analogy that
we're jumping off cliffs and inventing parachutes on the way
down, and that's really emblematic of this project. We're
asking and hoping to answer the deepest questions. And you
don't know where they're going to lead.
Mr. Babin. Right.
Dr. Doeleman. If you limit yourself by attacking questions
that you can see what the return might be, then you're really
limiting where you're going intellectually and where we're
going as a human--as humans is by asking these open-ended
questions, that they inspire, as Dr. Cordova said, but also
that you get these amazing discoveries and the ancillary
benefits.
Mr. Babin. Right.
Dr. Doeleman. Any normal portfolio advisor will tell you,
you want some stocks, you want some bonds, but you also want
some high-risk, high-return in there somewhere just on the off
chance you're going to invest in Amazon or something like that.
And sometimes it pays off, as it did here, and it really does
inspire people. So if you want to make the discoveries and, you
know, have the benefit, you've got to take some--a little bit
of risk.
Mr. Babin. Yes. Absolutely.
And, Dr. Lonsdale, we're running out of time.
Dr. Lonsdale. Yes, thank you. Yes. I'll try and be brief.
So I--for me, I already mentioned the inspiration aspect for
young people and getting people into STEM. I'd also like to
very briefly mention that my observatory, we have an
interdisciplinary research program. The techniques and
technologies that went into EHT echo throughout all of the
research that goes on at the observatory, and I think that
that's true on a broader front as well. So, you know, we do
geospace science, for example, and it's benefited from some of
the work that's gone on at the EHT.
Mr. Babin. Right. Thank you.
And can we indulge Dr. Bouman for just a second?
Dr. Bouman. Sure. So I think I want to just echo everything
that my colleagues have said here. I think the technology and
basic science really drive each other to be better. And things
that we developed for imaging a black hole we don't necessarily
know how the--what they'll manifest in technology of the
future, but I think that they definitely will. I'm very
confident of that. And I also think that just capturing the
imagination of young students and turning them--getting them
excited about science and STEM I think that in itself will lead
to a lot of innovation in the future.
Mr. Babin. All inspirational answers. Thank you very much,
and I yield back.
Chairwoman Johnson. Thank you very much. Ms. Horn.
Ms. Horn. Thank you, Madam Chairwoman. And thank you to all
four of you. What an exciting and important conversation and an
inspiration this discovery is. I think, Dr. Cordova, the
inspirational factor I think can't be undervalued and the
discoveries that come after that.
And, Dr. Bouman, I want to turn to you first because we
recently had a hearing on diversifying STEM fields with some
really fantastic witnesses as well, and I think you are a prime
example of what that looks like and how a diverse pool of
scientists is important and can bring different things. So my
first question really, as we work to inspire the future
generation is what inspired you to pursue this field of study?
Dr. Bouman. Yes, so I think, you know, I didn't ever expect
to come into this and work on this to be a figure of diversity.
You know, I was just excited by the science, excited by, you
know, the mystery of what we were working on and what we could
achieve together as a team. And I think that highlighting just
not my story but the stories of many different scientists in
the collaboration who come from many different backgrounds who
have many different experiences I think is wonderful, and I
think that many--as we've been talking about, young students
and getting them excited, it's important to show the diversity
of people that was necessary to make it possible to get this
picture because we required that we had many different people
that kind of came to it with different ideas of what should we
do and we kind of whittled it down to the best of the ideas,
and I think that was really essential.
Ms. Horn. Thank you. I think that's an incredibly good
point is it's not diversity just for the sake of diversity but
creative new ideas and perspectives that people from different
backgrounds, different experiences can bring to the table.
So following along those lines, I'd like to know a little
bit more about your early research and the contributions and
how you see that as helping to shape your next step as you move
into becoming a professor, so----
Dr. Bouman. Yes, so I've learned a lot through the Event
Horizon Telescope project. One thing that it provided--the
Event Horizon Telescope project provided is many different
opportunities for leadership, and there were many
opportunities, and many different parts of the project were
kind of guided by people such as myself, early-career
scientists, and kind of we led the direction of different parts
of the project and had to come up with creative solutions to
problems that kept popping up everywhere.
And I think by doing this and having to lead teams of tens
to hundreds of people in this and kind of converging on one
story and one kind of result was really helpful for me in my
next stages of my career where hopefully, I'll--you know, I'll
be leading a group of students there, and I think that the
skills that I learned as part of EHT will be invaluable for
that and something that I think is rare to have at a young age,
and so I'm really--I think that EHT is doing a wonderful job of
providing that opportunity for young scientists.
Ms. Horn. Thank you very much, Dr. Bouman. I agree with
you. It's easier to envision yourself as something that you can
see, and I think there are a lot of ways that we can do that.
I want to turn to Dr. Doeleman for just a moment in the
little over a minute we have remaining. And I want to ask, Dr.
Doeleman, what can we--what should be done to help you in
recruiting and maintaining postdocs and other students to help
continue to grow the pipeline of scientists and researchers?
Dr. Doeleman. Thank you for the question. I just want to
amplify something that Dr. Bouman said, that there is no EHT
101 course taught in astronomy curricula. Doing something new,
so fundamentally fresh like this requires that we draw upon the
best from many, many different fields. So I think the thing to
do is to invest in some interdisciplinary positions, you know,
perhaps postdocs and graduate student positions. At Harvard,
for example, we started the Black Hole Initiative, which brings
together mathematicians, physicists, astronomers, and also
philosophers and historians of science, all of whom see the
black hole as an anchor point in their respective fields. And
in that crucible of interdisciplinary kind of mishmash of
wonder, we've--we're now graduating our first students who have
exposure to all of these different fields together. And that is
really something that I think lifts up the EHT and it provides
an example for the kinds of students and early-career people
that we need.
Ms. Horn. Thank you very much. My time is expired. I just
want to say thank you to all of you for the work you're doing,
and it's really great to have you here. I yield back.
Chairwoman Johnson. Thank you very much. Mr. Posey.
Mr. Posey. Thank you, Madam Chair, for holding this
hearing, and thank all of the witnesses for appearing before
what is clearly the most interesting and the most exciting
Committee in Congress. I so enjoy it. And you just bring yet
one more incredible dimension to the things that we get to
explore with you.
You know, Dr. Cordova and Dr. Doeleman, given your
statements that the capture of the first-ever image of a black
hole by the EHT would not have been possible without American
leadership, I just wondered if either one of you could
elaborate just a little bit on some examples of what you mean
by that.
Dr. Cordova. Well, in this case what I really mean is we
were in it for the long haul--and that's true with most of the
projects that we do of this nature--we've been funding this
project for about 20 years or so. And we funded the LIGO
gravitational wave project for 40 years. We consistently fund
high-risk but potentially high-reward projects, so that was
just essential in this case.
Mr. Posey. OK. Dr. Doeleman?
Dr. Doeleman. Yes, if I could expand on that, and spring-
boarding off of what Dr. Cordova said, this project started
some time ago and was quite risky at the first stages. We
really didn't know if there was even anything that small toward
M87 or the galactic center Sag A* that Dr. Bouman talked about.
And it was some early proof-of-concept experiments using
cutting-edge instrumentation by primarily U.S. groups that set
the stage for the eventual buildout of the EHT.
And so when we talk about leadership, it grew from a
history of taking risks and being at the forefront at the very
outset of the project. And then, as it became clear that the
project could succeed, then we began to attract more
international investments and investments even from within the
U.S., so it grew but always with a nucleus of some U.S.
expertise at its core.
Mr. Posey. You know, if somebody had told me we're going to
locate and coordinate these various telescopes around the globe
and we're going to coordinate them so that you could read the
data on a dime from New York with the dime being in Los
Angeles, I'd think that's insane, so, you know, a lot for your
courage and your faith in what could be accomplished.
Dr. Lonsdale, anything you'd like to comment?
Dr. Lonsdale. Well, certainly the accomplishment is
something to be very proud of. The--I look at the scale that we
were able to magnify this thing to, and it still blows my mind
now even though I was deeply involved in it right from the
beginning.
As Dr. Doeleman said, the National Science Foundation has
been supporting this work--actually I think the foundations of
this go even before 20 years ago when we started working on 3-
millimeter VLBI in the mid-90s. So we've been--the foundations
for this have been going on for a long time, and it was really
quite visionary on the part of the National Science Foundation
in my opinion to have sustained investment in this, and it
became apparent, as Dr. Doeleman said, that the event horizon
scale structure could be accessed. I have to admit I was
skeptical initially. Dr. Doeleman convinced me after a bit of
time, but it's been a wonderful experience and a wonderful
ride.
Mr. Posey. And, Dr. Bouman?
Dr. Bouman. Yes, I think it--one thing that has made this
so strong is that we do have--you know, to make a global
telescope, we have a global team, but it has been, you know,
from many students--from students to, you know, senior
scientists from the United States have really pushed this
project forward from the beginning, and I--you know, as a
younger person see this in my mentors, but I think that it's
wonderful how they've kind of had the courage to stick with
this for the last, you know, 20 years to achieve what we have
today, so I think it's wonderful.
Mr. Posey. You know, I don't think the accomplishment could
be overstated, and I just hope the public learns more about it
and would have to become excited about it and more about
science and especially our young people.
Thank you, Madam Chair. I see my time is up. I yield back.
Dr. Doeleman. OK. I was--can I add one last thing? Would
you mind? Yes. One thing that I think needs to be said is that
the U.S. attracts the best and the brightest really. We have
some of the best research universities in the world, and we get
a result like this, we get a lot of interest from around the
world from postdocs, from graduate students, from early-career
researchers who want to come and join the team here in the U.S.
So this is really a recruitment moment not just for early-
career or early STEM people but it's a way for us to get the
best people here. And some of them go back, some of them stay
here, but they all infuse the project with their intellect.
Mr. Posey. Thank you. Thank you for sharing. Thank you,
Madam Chair.
Chairwoman Johnson. Thank you. Mr. Beyer?
Mr. Beyer. Thank you, Madam Chair, and thank you guys for
coming back again. I've had a chance to be here on a fly out
day when you presented a couple weeks ago, and it was very much
fun to see it, but I was also incredibly impressed with the
quality of the questions asked by our staff, and I was
impressed to find out that we now have four astronomers and two
physicists just on the Democratic side, and of those six, four
of them are women, which is another thing to celebrate, so it's
great to have you back.
Dr. Doeleman, you talked about how you might be able to
make a movie of the black hole. How will that be different from
Matthew McConaughey flying into the black hole in Interstellar?
Is that what you're envisioning or----
Dr. Doeleman. Well, we're hoping to bring him onto our
team.
Mr. Beyer. Put Ed Perlmutter on the team, too, please.
You'd be glad to have him.
Dr. Doeleman. But it's a great question. The human
intellectual palate gets sophisticated pretty quickly, so it
wasn't 5 minutes after we released this image that people were
saying, well, what's next? And we were, too, quite frankly. I
think we were all asking what's next.
By making movies, we access a completely different realm,
as Dr. Bouman was saying. We can add some new telescopes around
the globe to sharpen and fill out the virtual lens, and by
seeing the motions of matter orbiting around, which can't of
course move at the speed of light, we test Einstein in a
completely different way.
And for Sag A* it was very important. It's a completely
different kind of object. Keep in mind that it's 1,000 times
smaller in mass than M87 here, so it's a completely different
kind of object from an astronomical point of view. It's much
more similar to all the black holes in most of the galaxies in
the universe, so by being able to study Sag A*, we can study
most of the universe.
Mr. Beyer. You set up my next set of questions because I
was very much intrigued that you guys hadn't been smart enough
to come up with a theory of quantum gravity yet, so I've been
asking a lot of people about it since and reading up on it, and
I've long been a fan of string theory because the math works,
right? But in string theory you have 26 dimensions, bosonic
string theory; super string theory, 10 dimensions. How does
this work on imaging a black hole help you think about quantum
gravity?
Dr. Doeleman. Yes, so it's a really good question. So on
the scale of the event horizon, we tend to think of black holes
as classical objects. In other words, the quantum realm doesn't
really take hold until you get to the singularity that's
shrouded by the event horizon. When you get to that
singularity, the density is so high and the force of gravity is
so strong that finally gravity gets to play with the big forces
like the strong force and the weak force that control things at
the nucleon level. And only there does that happen. That's
where we need to unify gravity and the quantum world.
At the event horizon, we don't think there's going to be
much effect on quantum gravity there, but there could be. In
other words, there are some theories where you get
manifestations of the quantum world on horizon scales. And
people have done some simulations now of what that might look
like.
Mr. Beyer. When you get to the singularity, will you be
able to think about things like quantum entanglement?
Dr. Doeleman. It's possible. I'm not sure--I'll be honest
with you. I'm not sure how the Event Horizon Telescope is going
to see through the event horizon. We haven't quite got there
yet. But if the quantum fluctuations can be manifest outside
the event horizon, then looking at the electromagnetic
radiation from the black hole boundary, as the EHT does, could
give us a window into that.
Mr. Beyer. So all of us here are big fans of James Webb,
we're all big fans of WFIRST (Wide Field Infrared Survey
Telescope). Will this work also give you insight into dark
energy and dark matter? Or is it----
Dr. Doeleman. It is possible to think about dark matter and
dark energy from this perspective, so, for example, there are
theories that dark matter consists of, you know, black holes
and things like that. And there are also some possibilities
that axion particles, which could be the constituents of dark
matter, dark energy, could be resolved or studied with the
Event Horizon Telescope, but that kind of remains to be seen.
That would have--be through a next-generation version of it.
Mr. Beyer. OK. Dr. Cordova.
Dr. Cordova. If I could just add that NSF has some other
telescopes coming online like the large spectroscopic survey
telescope, the LSST in Chile, that is going to really address
dark matter and dark energy.
Mr. Beyer. Great, thank you. And, Dr. Bouman, it was fun to
read in Dr. Cordova's statement about the 1,000 hard disks and
too much data to go over the internet and three tons. So you're
a computer scientist. What's coming in terms of data management
to be able to deal with these huge amounts of data?
Dr. Bouman. Yes, well, luckily, from an imaging point of
view, by the time we start making the images, this data has
already been whittled down to a much smaller amount of data,
and then our problem is we have too little data. But actually
there are groups of people who take the five petabytes of data
that we collected and get it down to megabytes. So basically
they try to find this weak signal riding on a huge amount of
noise and process it down and calibrate it so that we kind of
can make these measurements that we then use to make images.
But even then this has required, you know, huge amounts of
computational power to whittle--to make these five petabytes
down to the megabyte level. I'm going to--I think Dr. Lonsdale
will have a lot to say along that line.
Dr. Lonsdale. Yes, well, just briefly, one of the biggest
challenges that we face is actually taking the data from the
telescopes where it's recorded and physically moving it to one
place so we can combine it. And that's a particular problem for
the observations taken at the South Pole. Of course, these
observations happen in the northern spring, which is when
winter is closing in in Antarctica, so we can't even get the
data physically for months and months and months. And ways to
ameliorate that problem are under study, including the
possibility of laser-based communications via space relay,
which has the potential for enormous data rates that would
allow us to get the data much quicker and do the whole process
more efficiently.
Mr. Beyer. Great. Thank you very much. Madam Chair, I yield
back.
Chairwoman Johnson. Thank you very much. Mr. Perlmutter.
Mr. Perlmutter. This is an incredible panel. I just thank
you. The enthusiasm, as Mr. Casten said, it really is
infectious.
So many, many years ago I wrote my term paper in astronomy
on black holes, OK? And I love volcanoes and I got to go to the
Atacama Desert to the observatory there, which is surrounded by
volcanoes and was focusing on the black hole. They didn't tell
us the discovery, but they told us there was going to be big
news coming. So you had a cone of silence, but they definitely
gave us an indication what was coming.
And one of the things that I saw that was incredible was
the teamwork among the scientists of all the different, you
know, departments that you might be--in English, in Spanish, in
Czechoslovakian, so we had young scientists down there with--
you know, running the computers, and they were all working and
each of them could speak the other's language.
So tell me a little bit about it, what it was like working
with some of--and all of you, you know, some of your colleagues
from other parts of the world because this was an incredible
amount of teamwork. And then I want to talk about time travel
after that.
Dr. Doeleman. Well, so, yes, maybe we could solve the time
problem by first inventing time travel, and then we'll have
more time to answer the question.
Well, I think that one of the points of pride in this
project really is that our strength is in the diversity of the
team, and the strength is in building bridges across borders at
a time when I think, as the Chairwoman said, things can divide
us. The technique that we use, very long baseline
interferometry nimbly sidesteps all of that in a natural and
organic way to work with the best experts around the world to
build this global telescope with a global team.
And we ensured that, as I said before, by establishing
working groups, the imaging working group that Dr. Bouman is
in, technology working groups that Dr. Lonsdale participates in
by making them interdisciplinary and by drawing on the
different constituents around the globe as the fabric of it.
And when you do that and when you bring everyone together, you
find out quickly who can do the work regardless of where they
are, and you crosscheck everyone.
And it set up, that environment that I called purposeful
tension before. It really is a way to gain acceptance for your
results when everybody's looking at it and everybody's asking
questions regardless of language or culture or background.
Dr. Lonsdale. So I want to emphasize the VLBI technique.
It's been around for a long time. And because it involves very
long baselines, it automatically is international. It's been
international for 50 years. And there is, you know, a real
sense of community in the VLBI world and everybody's friends or
nearly everybody is friends. But, no, I mean it's really a
wonderful community, and it's been a delight to work in VLBI
for the last several decades.
But in the EHT, there's also a key factor that ties
everybody together. Everybody is totally driven by the mission.
There is a tremendous drive on the part of everybody to get to
results like this, and that crosses all barriers. And so when
you combine those two things together, that I think is the
spirit that you witnessed at the ALMA site in Chile, and it's
across the project.
Mr. Perlmutter. All right. So let me just jump to time for
a second. So does that picture tell you anything about time and
what it is?
Dr. Doeleman. OK. I guess I'm going to be the sacrificial
lamb here on this one. Well, I'll just say that there's no real
indication that we can make inroads on time travel using these
results. In one sense you're actually looking at a time machine
because this black hole is 55 million light-years away. The
images that you see is the way the black hole looked 55 million
years ago. So in that sense we're seeing something that left
the black hole when, you know, the dinosaurs had just been
extinct here on the Earth.
Mr. Perlmutter. But going back to the question about
Matthew McConaughey and Interstellar, does this, what you've
done, help prove up some of Einstein's theory about time and
space and something as dense and as massive as that?
Dr. Doeleman. Yes, absolutely it does. So what you're
seeing here is the strongest proof we have to date for the
existence of supermassive black holes, full stop. It really
validates Einstein's theory as to the precision of our
measurements around this black hole. For example, Matt
McConaughey went to this fictitious black hole, and he went
close to it and he came back and he had not aged as much as a
companion astronaut in the mothership that was--had not gone
down into that gravity well. That is a real phenomenon. You can
go to a black hole, you can go close to it, your clocks will
tick much more slowly than clocks farther away. And so in that
sense we have validated Einstein at the black hole boundary and
maybe put Interstellar on slightly better footing.
Mr. Perlmutter. Thank you, and thanks, Chair. I yield back.
Chairwoman Johnson. Thank you very much. Ms. Stevens.
Ms. Stevens. Well, thank you to our incredible witnesses
for today's hearing. There's a reason why we're doing this as a
hearing today rather than a meeting, and that's because we are
showcasing to the world from the halls of Congress your
incredible achievement and accomplishments for humanity that
really just put us at a tipping point frankly.
And the question I wanted to ask was around the technology
and the data sets and the logarithms. And I was wondering, many
of you have it in your testimony, but I wanted you to shed
light on that technology and what that means for us in our
everyday lives and what this means for us as, you know, a
society and other applications that we maybe could use these
data sets for. And, Dr. Bouman, if you would like to start, I'd
love for you to take that question.
Dr. Bouman. Sure. So I've talked with--a little bit so far
about how the methods that we've developed for imaging a black
hole can be applied to many different applications. I've
highlighted MRI taking better images of our brains and organs
that are moving, and that can be--it's a very similar problem
to imaging an evolving black hole overnight. I think there are,
you know, a myriad of different applications, and so many of
the applications today require that we take multi-modality
information, sensor data, and merge it together with algorithms
that kind of piece--that kind of fill in our gaps of
information to come to some result. And I think that the
merging of sensor data with algorithms, especially with--in
machine learning where we're coming up with new computational
techniques to push the boundaries of these methods.
I think the methods that we develop for the black hole
imaging are similar in spirit as these other methods, and we
have to come up with similar--there are similar problems with
them as well like validating the information, making sure that
these systems are robust under--in different situations, making
sure that we don't impose too much prior information on our
result, and then we can see something unexpected. I think that
these are similar problems throughout a variety of
applications.
Ms. Stevens. How many people worked on the data set?
Dr. Bouman. So the imaging portion of it is only one small
part of making an image of a black hole. There are many
different steps from developing instrumentation, you know,
installing these at the ends of the Earth in the South Pole
even, you know, through data processing. Whole new data
processing pipelines had to be developed with the challenges of
the EHT in mind. Even though we were building on past VLBI
technology, these kind of had to be modified for the challenges
we faced. Imaging and then model fitting and theory,
understanding the interpretation, all of these were essential
parts in getting that picture.
And so we had over 200 collaborators on the EHT project----
Ms. Stevens. Wow.
Dr. Bouman [continuing]. And there were additional
collaborators who were not part of the collaboration who also
were essential to making it possible.
Ms. Stevens. So this was the international collaboration
that we've been talking about that these large challenges,
these big visions are really met by coming together, and that's
something that we spend a lot of time on the Science Committee
exploring and talking about, which is how to forge unlikely
alliances, how to set the table. And frankly, that's something
that the Federal Government does really well when it's working
well is bringing folks together.
I have one last little question about the black hole. And
Mr. Perlmutter got into some of the fun of this, but you sort
of with your work have begun to normalize the black hole, which
was sort of just this big vision and debated if it was true and
what it is, and I was just wondering if you could shed light on
how one cannot get lost in the black hole as it pertains to the
work that you're doing? That's somewhat of a poetic question,
but I ask it because your work has implications for what we are
doing on the Science Committee and how we are inspiring
research.
Dr. Doeleman. That's an interesting question. Let me try to
answer it. Maybe you can course-correct me if I go astray here.
One way to look at this and not get lost in it is to put it
in historical context. So think about in 1655 there was an
image that startled people. It was the first drawing of a flea
by Hooke. The microscopic world became real for us. All of a
sudden something that was invisible to us became real, and it
changed the way we thought about our lives and it changed
medicine and disease and epidemiology just knowing that there
was this microstructure.
And think also about the first x-ray made by Roentgen of
his wife's hand. You could see the ring on the--with the bony
structure underneath. It made something visible for the first
time that was invisible prior to that.
And then think of the Earthrise over the moon, the first
blue marble. It really put things in perspective for us. It
made us feel connected in a way that we hadn't before. It made
us feel vulnerable. These are iconic images. They're
terrifying, but we can't look away.
And I think that if you wanted to get poetic, using your
words, that this image may become an icon. It may be the first
image we have of a one-way door out of our universe. It's
something that we've been taught that is a real monster exists,
that the visible has become visible. And then the maybe it's
the beginning of something new, not just the end.
Ms. Stevens. Thank you. That's exactly what I was looking
for. And I yield back the remainder of my time.
Chairwoman Johnson. Thank you very much. Ms. Wexton?
Ms. Wexton. Thank you, Madam Chair, and thank you to all
the witnesses for being here today. I am really in awe of all
of you and everything you've accomplished, and it's fantastic
that you've inspired a new generation of Americans and beyond
to pursue science and to look beyond our horizons.
One of the major--and this is something that the gentlelady
from Michigan touched on a little bit. But one of the big
challenges that you had to overcome was the huge volume of data
and--that was generated and how it had to be transported
because you couldn't use the internet to transport a lot of it
and analyze. Dr. Cordova, can you talk a little bit about the
need for new approaches to big data given the volume of data
that we're seeing now and breakthroughs like these?
Dr. Cordova. Yes, this is a great example that put into the
spotlight. One of our 10 Big Ideas for investment is called
Harnessing the Data Revolution, and it's really a response to
this enormous challenge that we have not just in this field but
in all fields of scientific endeavor and other endeavors now.
And we need to be continually stimulating the imaginations of
would-be proposers and grantees to think about how we're going
to effectively do data analytics and data science on this
enormous scale of data that we have. We have a lot of grant
opportunities to propose for new kinds of platforms and ways of
thinking about this.
We're also working in collaboration with the private
sector. We have, for one example, a collaboration with Amazon
where they're putting in $10 million, we're putting in $10
million to work on artificial intelligence and see where that
can take us in looking at how to do data science better.
And in our new convergence accelerator, we have a fast
track to try to get a platform where people can access
databases that may look completely different and actually kind
of speak different languages. How do we interrogate them so
that the average individual can go in there and say, I can
understand how to use this database and this one and this one,
and put them all together in order to synthesize a new
knowledge from and extract the answer to new questions.
It's just an enormous challenge that our society, because
it is technologically advanced, now has, and I think this
illustration of the EHT project really puts that in focus.
We're not just talking about 15 terabytes a night, which is
what we expect on a telescope like the new one we're building
in Chile, the LSST, but we're talking about much more.
Ms. Wexton. And related to that I guess or as a part of
that, I understand, Dr. Bouman, that the computer algorithms
that were used to construct the image that was--that they
leveraged open-source software, is that correct?
Dr. Bouman. Yes, that's correct.
Ms. Wexton. So I would ask everyone on the panel, what in
your view is the value of open-science practices such as making
computer codes and raw data available to the public? How does
that help spur innovation?
Dr. Bouman. Yes, so the algorithms, the code that we write
to make images of black holes to model to extract the mass,
many different aspects of the project we leveraged open-source
software. And without this, you know, it would've taken us many
more years to develop the tools necessary to do this. So we
gained a lot. And if you look at the--basically the tree of
contributors toward the project, it's not just the--tens of
people, it's not hundreds of people in our collaboration but
it's thousands of people that have really contributed to making
this project through open-source software. And so I think it is
really essential.
And in giving back to the community and also trying to
expedite, you know, these results and acceptance of results,
we've also made our code and algorithms available through open-
source software online, along with the data that we used to
make the picture so you can go off and develop your own methods
to try to make a picture of a black hole as well. And so we are
in big support of open-source software and pushing and
continuing to do that.
Ms. Wexton. Thank you. Dr. Lonsdale, do you concur with
that?
Dr. Lonsdale. I fully concur with that, yes. I think it's
been a tremendous accelerant for our work. It's made the work
much more efficient, much more cost-effective to be sharing
these kinds of codes and--through the open-source mechanism.
Ms. Wexton. Dr. Doeleman?
Dr. Doeleman. Go ahead.
Ms. Wexton. OK. Very good.
Dr. Cordova. I just would love to give you a recent example
of where open data has really increased discovery. I recently
visited Princeton University, and two young astrophysicists
there took the entire database from the first two runs of the
LIGO observatory that discovered gravitational waves, and with
their own computer there and their own imagination and brains,
they went through the entire data sets and discovered six more
emerging black hole binary sources, which the original team had
not found, but just because they had their own kinds of
algorithms that they had developed to reduce the noise. The
potential of releasing data and of course software is just
enormous for discovery.
Ms. Wexton. Thank you.
Dr. Doeleman. Would you mind if I said one more----
Ms. Wexton. I will inquire, but Madam Chair says it's OK,
so yes.
Dr. Doeleman. I would say often people say--like Newton,
you know, said he stood on the shoulders of giants, a couple of
giants. But with open-source software, many hands make light
work, and so you can get thousands of people helping. And I
would also add just very quickly that it's a way to get buy-in.
It's a way to make people feel like they're part of something
like this. So the people that wrote the libraries like, you
know, Num Pi or Astro Pi that we use just to get a little wonky
and some of the software that we use, they can look at this and
feel a little sense of ownership, that they're part of it,
right? So when you get such a result like this, and many people
have contributed, everyone sees their self in this kind of
project.
Ms. Wexton. Thank you very much. Thank you, Madam Chair.
Chairwoman Johnson. Thank you very much. Mr. McNerney?
Mr. McNerney. Well, I thank the Chairwoman for holding this
fun hearing. I want to thank you, Dr. Cordova, for your
leadership in science. I want to thank Dr. Doeleman, Dr.
Lonsdale, and Dr. Bouman, for your dedication and hard work. I
know how hard science is. You've got to spend a lot of hours
alone in the lab and in front of your computer screen. When
you're in college, your friends are out partying. After
college, they're out making money. But they don't understand
the kind of reward you get when you make these kind of
discoveries, so thank you for your hard work.
I studied differential geometry and general relativity in
grad school, so it was particularly rewarding to see these
images.
Because of your hard work and the hard work of many
dedicated scientists who are now, for the first time, able to
create a definitive image of a black hole, well, we can't see
black holes but we can see the effect of black holes, and we
need to think of black holes as something bigger than
ourselves. It's a punchline.
So this announcement was also a monumental moment for STEM
education, which forms one of the cornerstones of the United
States educational system. Dr. Cordova, exciting advances in
science often inspire students to pursue STEM careers. However,
not every scientific breakthrough gets this kind of attention.
What steps is the NSF taking to engage young people when
exciting discoveries are made in other fields?
Dr. Cordova. Thank you, Congressman, for that question, and
thank you for always being a partner with NSF on its trips to
both Poles and to the adventure of scientific discovery
globally.
NSF has many, many programs to stimulate the imagination of
young people. Some of the particular programs are Computer
Science for All, or CSforALL it's called, which gets young
people with the imagination of a Dr. Bouman at an early age
involved in having the computer skills and literacies to go on
and then go in any direction that they want, in science,
engineering, finance, whatever.
We have a lot of programs to increase inclusiveness and
diversity of the STEM workforce at all ages. We have programs
to advance women and underrepresented minorities through the
pipeline of academia and beyond. It's a major emphasis of ours.
In this particular discovery, I just have to credit the
people that are in our Office of Public Affairs for seizing on
what it would do to the imaginations of everybody, young
people, older folks around the world, and realizing very early
on, when you are submitting your first papers, that this was
going to be the discovery which, when other people saw it,
would just absolutely mesmerize. There would be a world pause
to say, wow, you know, did that really happen?
And they just coordinated in a way to organize really the
entire world. There were I think eight press conferences
simultaneously around the world to announce this. It was just a
major thing. Now, we can't do that every day. We don't have the
workforce to be able to do that, but----
Mr. McNerney. Well, I'd like to ask another question now--
--
Dr. Cordova. Yes.
Mr. McNerney [continuing]. If you don't mind too much.
Thank you.
Dr. Doeleman, did you use deep learning or other AI
approaches in developing this image?
Dr. Doeleman. Well, I am--I'll give you a quick answer, and
then I'd like to defer to Dr. Bouman on that. We didn't
necessarily use artificial intelligence or deep learning as
such. We did use very forward-looking new algorithms. So we
created this tension in the program where we used traditional
methods using radio astronomy, but also new methods invented
purposefully for these data. And when we got corroboration
between them, that was powerful evidence that we were on the
right track. But we look forward to using these new kinds of
techniques, deep learning, AI as we move forward in some of the
videomaking that we plan on doing. But maybe Katie--or Dr.
Bouman wants to----
Dr. Bouman. Yes. As Dr. Doeleman said, it was very
important that--for these first results we were as confident as
possible in them and so we had many different methods, both
traditional and new methods that we had developed
independently, and we actually imaged independently. And when
we saw the same structure out of all--both of them, then we
were very confident.
We have explored other machine-learning and deep-learning
techniques for making images of black holes. However, we--this
data was so amazingly beautiful that we didn't actually need
these very complicated methods to get something robust out of
it, so we actually decided to pare down and do basically the
algorithms that we were most confident with in the community
and had most acceptance within the community because they
produced beautiful results themselves. And we actually liked it
when we didn't have to impose as much assumptions into the
problem.
And so I think moving forward, as we get harder and
harder--data that is harder to work with, it will be essential
that we merge in these new computational methods, deep-learning
methods, other AI techniques with the data to get the best
results. But for this result we found it wasn't necessary and
so chose not to use them.
Mr. McNerney. Well, thank you. I'm going to just ask one
quick question. Could you possibly describe how you felt when
you first saw that image on your screen?
Dr. Bouman. So I think we all have probably different
stories for this, but I was personally in disbelief. You know,
we had worked for years developing the methods, testing them,
making--you know, but until you saw--we all kind of crammed
into a little room, very hot, it was June, and we all pressed
go on our computers at the same time. We all had an imaging
script ready to go. And as the image--it just like started
appearing, this ring shape, and I think none of us were really
expecting that to happen. You know, we had for years been told,
oh, you would--we would expect to get a ring, but you never
know.
Everything--there's always something that goes wrong,
right, so seeing something like that just appear on the screen,
I kept going between excitement, awe, disbelief, and just
hoping that it wasn't some cruel joke that was being played on
us and it wasn't real data. So it took me a month before I was
convinced it was real, but I was very excited. We were all very
excited.
Mr. McNerney. Yield back.
Chairwoman Johnson. Thank you very much. Dr. Foster?
Mr. Foster. Thank you, Madam Chairman, and thank you to our
witnesses.
I have to say that, you know, this hearing has brought back
a lot of memories to me. I was fortunate enough in my career in
science maybe 2-1/2 times to have been at that screen seeing
the results of your data analysis and learning something that
previously was only known to, you know, your data and to God.
And so it is an incredible feeling.
I remember the first time--my Ph.D. thesis was the search
for proton decay, and for my thesis we built and designed and
did the data analysis for a giant detector in a salt mine to
look for proton decay, which was confidently predicted by the
huge majority of theoretical physicists. And so we had multiple
data analysis programs, and mine ran a lot faster than everyone
else's, so I knew the answer first.
And so when we saw the first few days of data, realized
that we were seeing neutrinos at the expected rate and not a
sign of proton decay, you just sort of sit back in your chair
and say, wow, all of these theorists were wrong.
About 160,000 years ago, a supernova blew off in the
greater Magellanic cloud, and for 160,000 years the burst of
light and the burst of neutrinos traveled toward the Earth and
arrived in 1987. And where the signal was seen optically by the
astronomers and at the same time in our underground detector
what we saw neutrino burst. So at that time we were also
limited by data transmission. And one of our collaborators
drove down to the mine underneath Cleveland and then took the
actual magnetic tape, which is how you move data, drove it to
Ann Arbor where the analysis computers were, spun the tapes,
did the analysis, and then realized that, yes, indeed, we had
seen the neutrino signal and learned a lot about these
incredible explosions.
I guess the third time was when I was working on the giant
particle collider at Fermilab and I was looking for the
discovery of the top quark into the decay mode of electron and
muons. And so I had something that--looked every night, would
spin through the interesting events on the last night's data
and saw one morning when I was drinking my coffee that in the
previous night we had seen an acollinear muon and electron
event with enough energy that it pretty much had to be the
decay of a top-antitop with a top mass of about 170 GEV. And
so, you know, you see this thing and say, my gosh, that's it.
And that's why you get into this business. I understand that
smile that's on your face.
Before I forget, I would like to ask unanimous consent to
enter into the record of this hearing the entire author list of
your publication. You know, it is a tough thing to try to, you
know, spread the glory for something like this appropriately
because you have everything from the technicians that stay up
all night and repair the circuit boards when they break in the
middle of the night to the people that are really good at
giving talks and so they always get sent to the big
conferences, and then--it's a tough thing, and it's wonderful
to have people with the entire range of skills on the author
list. So I'd ask unanimous consent if it's----
Chairwoman Johnson. So ordered.
Mr. Foster. Thank you. And let's see. In my copious minute
and a half I have left, I'd like to talk a little bit about,
you know, the way forward on this, you know, what additional
facilities, you know, if you could, you know, ask for, you
know, a doubling or tripling of the effort in this area, you
know, what would be the top of the list of ways to really
expand your capabilities to do more of this kind of observation
and analysis?
Dr. Lonsdale. So I think very near the top of the list is
additional telescopes because they improve the fidelity of the
data, will allow us to see fainter things in a picture like
this. This particular object has a really spectacular jet of
material coming out of it. The only reason you can't see it in
this picture is because the dynamic range of the image, the
brightest to the faintest isn't big enough, and one of the ways
that you can improve that is by adding more telescopes.
And then, as Dr. Doeleman said, you know, increasing the
amount of data that we can take increases the sensitivity and
then going into space is the obvious next step because then you
can get a telescope as big as you can space your spacecraft.
Mr. Foster. And what is the scaling of your resolution with
the baseline----
Dr. Lonsdale. It's one-to-one. If you double the baseline,
you double the resolution of your imaging.
Mr. Foster. All right. And so you're not statistically
limited----
Dr. Lonsdale. You----
Mr. Foster [continuing]. For at least as long as you have a
handful of satellites?
Dr. Lonsdale. Yes, it's actually----
Mr. Foster. Or additional telescopes.
Dr. Lonsdale. It's a fairly complicated tradeoff. If you
have a low-Earth orbiting satellite, then it will get you a lot
of information very quickly but not such high angular
resolution. But if you have something further out, it gathers
data more slowly but has higher resolution.
Mr. Foster. OK. And just one quick question. Did you
publish the four pictures that got averaged to the final?
Dr. Doeleman. Yes. So----
Mr. Foster. You did. OK.
Dr. Doeleman. In the publication you see everything. Let me
add one thing to what Dr. Lonsdale said. You can have
telescopes, you can have satellites in orbit, you can do higher
bandwidths and you can go higher in frequency and sharpen the
image, but what I've learned in this project is it's all about
the people. You know, you can have the fanciest equipment that
you want, but if you don't have ingenious early-career
scientists like Dr. Bouman and her colleagues, if you don't
have people who are visionary in trying to see what they can
do, if you don't push the data in new directions--and having
the data is not always the final answer. So the other thing
that I think we need is--I would say is an influx of positions
that we can advertise to get the best and the brightest working
on these new data sets.
Mr. Foster. Thank you much. Among other things, making me
have a few tinges of regret at leaving science and getting into
this crazy business. Thank you all. I yield back.
Chairwoman Johnson. Thank you very much. Some of us are
glad you did.
I'm going to take the privilege of asking one final
question before we end. You have mentioned the international
collaboration, and we all know how important that is. But what
are some of the key contributions made by the international
partners involved in the project?
Dr. Doeleman. Thank you for that question, Chairwoman. So,
as I said before, different telescopes are in different
regions, so sometimes it naturally falls to the agencies or the
institutes in that region to care for or outfit that particular
telescope. So, for example, in Spain, one of our key telescopes
that provides an outrigger that fills out this Earth-sized
virtual lens was outfitted and maintained by the Europeans. And
they're also establishing a new telescope in France, which will
similarly round out the array. The Taiwanese are also working
on the Greenland telescope, which is going in that area, and
they're shouldering most of the burden there. And also we had
buy-in from the European Research Council to build out some of
the instrumentation that was deployed at all of the telescopes.
So in very key ways we levered the international resources, not
just the people but the resources, to build out the array.
Chairwoman Johnson. Yes, Doctor.
Dr. Lonsdale. I'd like to add to that the work that we do
at my observatory in correlating the data, combining the data
streams, that is done also at the Max Planck Institute for
Radio Astronomy in Bonn, Germany. And we've been close
collaborators with that group for decades in fact, and they're
part of this VLBI community that I had mentioned and we--and
the availability of a whole other team of people working on the
correlation so we could do definitive cross-comparisons between
what we were getting and what they were getting was an
essential part of the data validation process that was carried
through many different stages.
Dr. Bouman. Yes, just building on that, since we were
building this new instrument that we had never used before, we
needed to be very careful and test and make sure that every
stage of the pipeline was getting a correct answer. So each
stage from the correlation that Dr. Lonsdale just talked to, to
data processing to imaging to model fitting and theory, each of
these actually we developed different pipelines, different code
bases, or different methods to check each other. And in all the
cases that I can think of there was always an international
method or group that kind of spearheaded one of those at least.
And so I think it was really essential that we had these
independent tests of each other, these crosschecks to make sure
that our instrument was actually working as we expected. And
that required the help of our international collaborators.
Dr. Doeleman. Madam Chairwoman, if I could add one thing,
I'd be remiss, when you make lists like that, you always forget
someone, right? I would also point out that the Japanese
colleagues brought expertise in the area of imaging and also
really helped phase up the ALMA array, the array that Dr.
Cordova described. Our Chilean colleagues have worked very
closely with us on ALMA and outfitting that telescope. In
Mexico we had huge help from the institutes there with the
Large Millimeter Telescope on top of Sierra Negra. And also
in--from the Chinese, they also invested in the East Asian
Observatory, which brought us the James Clerk Maxwell Telescope
on Mauna Kea in Hawaii. So this really was a--truly a global
effort.
Chairwoman Johnson. Thank you. Any other comments?
Dr. Cordova. Since we're coming to the end of this session,
we want to mention about the Diamond Achievement Award that NSF
gave the EHT team and Dr. Doeleman accepted on--a couple of
evenings ago. So this is the highest award for really
remarkable achievement that we can give. And of course diamonds
spark all sorts of things in our imagination.
But I wanted to share with you something that I read in a
book that's already been written and published about this
project, a Scientific American writer named Seth Fletcher lived
with this team for 6 years and he went all over the world with
them, and he has a quote from Shep, who--they were at a very
critical point in the observations, lots of things going on,
and apparently Shep held his head and he said, ``I'm under so
much pressure I feel like I'm going to be squeezed into a
diamond.''
And that's when we decided we needed to call this award the
Diamond Award because to reach out to all those people, all
those scientists that--engineers that feel like they're under
tremendous pressure and they may become diamonds, that
sometimes they actually do become diamonds.
Chairwoman Johnson. Thank you very much.
Before we bring the hearing to a complete close, I really
want to thank all of you for being here. It's been a tremendous
hearing, and I think you got that indication with the
participation and the enthusiasm. I think you've rubbed some of
yours of onto us.
The record will remain open for 2 weeks for additional
statements from Members or any additional questions you may
have or for additional testimony.
The witnesses are now excused, and our hearing is
adjourned.
[Whereupon, at 12:17 p.m., the Committee was adjourned.]
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