Since the early days of modern cosmic exploration, Cornell scientists have led the way, from guiding rovers through the red dust of Mars to searching for other life in the universe; and from modeling exotic stars to detecting the faint ripples of gravitational waves.
They’ve also established important centers of research, with the Cornell-led Fred Young Submillimeter Telescope (FYST) in Chile poised to become the next innovator of cosmic discovery.
Powerful new telescope
“There is global excitement about FYST in the astronomy community. The design is completely revolutionary, the high-altitude site is spectacular and the instrumentation is at the cusp of technology,” says Martha Haynes, Distinguished Professor of Arts and Sciences in Astronomy emerita in the College of Arts and Sciences (A&S). “And we can plug in new cameras as the technology continues its revolution, which is something you cannot do with space telescopes. FYST will remain a technological innovator for years to come.”
The telescope will address some of the biggest questions in astronomy, including: How does the universe work? What is the nature of dark matter and dark energy? How do stars live and die? What happened in that elusive time after the Big Bang? How did galaxies form?
To answer these questions, FYST will repeatedly map the sky, enabling scientists to study the large-scale structure of the universe as well as study phenomena that change over time.
“The way FYST is looking at the sky is what we sometimes call ‘celestial cinematography’ – it’s making a movie of the sky at a part of the electromagnetic spectrum where it’s never been done before. Perhaps there are phenomena we didn’t even know existed that we’ll find looking at the sky in this particular way,” says Anna Ho, the Richards Family Assistant Professor of astronomy (A&S). “I’m particularly interested in studying cosmic explosions.”
At 18,400 feet high, the telescope sits just below the summit of Cerro Chajnantor in Chile’s Parque Astronómico Atacama, high above most troublesome atmospheric disturbances. Its innovative optical design will deliver a wide field-of-view telescope capable of mapping the sky rapidly and efficiently.
The telescope’s PrimeCam instrument, designed by Michael Niemack, professor of astronomy and physics (A&S), can hold up to seven changeable modules, giving FYST unique flexibility as a platform for new technologies. Niemack’s original designs have also been featured in instruments he built and designed for the Atacama Cosmology Telescope and the Simons Observatory.
One exciting application of FYST’s new design will be in the emerging field of line intensity mapping, which detects structures in the universe by mapping the integrated light from many galaxies over broad regions of the sky, says Gordon Stacey, M.S. ’82, Ph.D. ’85, FSYT project director and the David C. Duncan Professor in the Physical Sciences (A&S).
Because FYST’s wide field of view will enable scientists to see large-scale structures in the universe, “we'll be able to learn about when and how galaxies first formed and how they evolved from the earliest times to the peak of star formation in the universe about 11 billion years ago,” Stacey says.
FYST project scientist Nicholas Battaglia will be applying line intensity mapping in his research and is keen to use FYST to probe Cosmic Microwave Background radiation for clues about the early universe. Rachel Bean, the Jacob Gould Schurman Professor of Astronomy (A&S), is especially excited about FYST’s multi-frequency capability, which will allow galaxy clusters to be used as powerful cosmological probes.
FYST is a project of the Cornell-led CCAT Observatory, Inc., a collaboration that includes Germany’s University of Cologne, University of Bonn and Max Planck Institute for Astrophysics in Garching, and a Canadian consortium of universities led by the University of Waterloo in conjunction with Chilean astronomers through the University of Chile.
The project has received crucial support from Fred Young ’64, M.Eng. ’66, MBA ’66. “Fred's been brilliant, a steady hand behind the tiller,” Stacey says. “We've also had very important support from Cornell, and with completion of the telescope imminent, we're also starting to attract new collaborators.”
“The inspiration for this world-class project came from the vision developed by the late Riccardo Giovanelli and Martha Haynes to exploit the unique potential for submillimeter wavelength astronomy at what is, arguably, its best site on earth,” Young says. “The loyal consortium of sponsoring universities, a welcoming, Chilean-based polity and I will enjoy enduring pride for years to come as astronomers exploit FYST to discover valuable scientific knowledge and students are inspired to pursue astronomy as a vocation.”
FYST builds on Cornell’s long tradition of leadership in submillimeter and radio astronomy instrumentation, beginning with the Arecibo Observatory in Puerto Rico, which Cornell built and managed for its first 48 years. During this time, Arecibo was the world’s largest radio/radar telescope; FYST now builds on that legacy as the most powerful telescope in the world for its mapping speed and sensitivity at its wavelength.
Finding Einstein’s gravitational waves
In 2015, the first ever discovery of gravitational waves produced by merging black holes opened an entirely new way to understand the universe, and Cornell researchers have key roles in both science and data management.
Two of these are Shami Chatterjee and James Cordes, pulsar experts who work on the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) collaboration. NANOGrav uses millisecond pulsars in the Milky Way to detect low-frequency gravitational waves. NANOGrav is now a National Science Foundation Physics Frontiers Center, for which Cordes, the George Feldstein Professor of Astronomy (A&S), is a co-principal investigator. Chatterjee, associate professor of astronomy (A&S), currently serves as the chair of the NANOGrav Pulsar Search Working Group.
As measurements continue to improve, the project expects to identify individual pairs of supermassive black holes for investigation, akin to picking out notes from a cosmic orchestra. Cordes is pushing this goal forward with his work to increase detector sensitivity and thereby obtain more accurate pulsar measurements. His in-depth examination of the astrophysical and instrumental effects involved resulted in a 200-page paper and textbook he is working on.
Ho, who has won multiple prizes for her work, is using the unique information provided by these waves to learn how the properties of stars during their lives connect to their explosive deaths and the corpses – the black holes or neutron stars – they leave behind.
“Black holes don't emit light, so we can't see them, but in the process of merging, they do produce gravitational waves that we can detect,” says Ho.
Adam Brazier is a computational scientist at the Cornell Center for Advanced Computing, which maintains an archive of the NANOGrav initiative’s data, and is an elected member of NANOGrav’s management team. Such computational and data management expertise is critical for the success of this research, as increasing the detection sensitivity for gravity waves requires long-term archiving, and building and maintaining the infrastructure for development of new algorithms and statistical methods.
It’s not just Cornell faculty helping advance gravity wave science at NANOGrav; Cornell has trained many of the researchers now serving in important positions in the project, such as Maura McLaughlin, Ph.D. ’01, who served as chair of the NANOGrav collaboration.
The Laser Interferometer Gravitational-Wave Observatory (LIGO) team that detected the first gravity wave based their technique on a theory developed by Saul Teukolsky, the Hans A. Bethe Professor of Physics and Astrophysics (A&S) and collaborator Lawrence Kidder, CCAPS senior research associate (A&S). Teukolsky and Kidder received a share of the $3 million 2016 Special Breakthrough Prize in Fundamental Physics. Teukolsky also received the prestigious Dirac Medal for this work, the first Cornell professor ever to receive it.
“Over my career at Cornell, black holes have transformed from a niche area of study to one of the hottest topics in physics and astronomy,” Teukolsky says.
Cornell scientists are also improving gravitational wave models through the Simulating eXtreme Spacetimes (SXS) Collaboration, for which Teukolsky is principal investigator. SXS has created a catalog of binary black hole simulations, using computer code written at Cornell, to help scientists analyze gravitational waves.
Computer simulation of what the first two black holes colliding detected by LIGO would look like. Credit: SXS Lensing
Simulations are crucial, says Nils Deppe, Ph.D. ’20, assistant professor of physics (A&S), because it’s impossible to experiment with black holes in a lab setting. The simulations will be essential for data analysis for the NASA-European Space Agency’s space-based gravitational wave detector, the Laser Interferometer Space Antenna (LISA), scheduled to launch in 2035.
Cordes also plays a key role in the forthcoming Deep Synoptic Array telescope, a Cornell-Caltech collaboration that will enable scientists to monitor more pulsars.
The same telescopes that provide data for NANOGrav’s pulsars also provide data about neutron stars and transient phenomena, like the fast radio bursts studied by Cordes, Chatterjee and others. The first repeating fast radio bursts were discovered in 2016 in a pulsar/transient survey at Arecibo that was planned and implemented by Cornell faculty, including Cordes and Chatterjee.
Scientists still don’t understand how and where fast radio bursts are produced, but they’re one of the best ways to probe the voids between galaxies and measure matter density there.
Chatterjee is a leading figure in fast radio bursts research, says David Chernoff, professor and chair of astronomy (A&S). “One of his most notable contributions was organizing people all over the world to make simultaneous measurements of one of these fast radio bursts and then putting it all together to figure out which galaxy the fast radio bursts lived in,” Chernoff says. “And that was the first definitive evidence that they were in other galaxies, not our own galaxy.”
Today’s discoveries are possible because of the emerging field of multi-messenger astrophysics, which combines information from multiple forms of data, including gravitational and electromagnetic waves, as well as neutrinos and cosmic rays, to study some of the most extreme and poorly understood transient events in the universe.
“This emerging field is exciting because only now do we have the capability to routinely ‘sense’ astrophysical objects in these ways, through gravitational waves and high-energy particles,” Ho says. “These additional messengers give us information that we can't get from the more traditional electromagnetic radiation (light)” – information on transient phenomena at the cutting edge of human understanding, such as the mergers of neutron stars, thought to be responsible for producing certain heavy elements in the universe, such as gold.
Exploring our nearest neighbors with NASA
Our solar system boasts a wealth of diverse worlds, from icy moons to desert Mars; from steamy Venus to the frigid remains of ancient planetoids. From the very first probes sent to Mercury, Cornell faculty have been involved in a majority of NASA planetary missions — and Cornell is one of few universities to lead such missions, including the highly successful Mars Exploration Rovers, Spirit and Opportunity.
Cornell’s expertise on Mars continues to fuel NASA’s missions to the planet today with the Curiosity and Mars2020 Perseverance rovers now roaming Mars. Alexander Hayes ’03, the Jennifer and Albert Sohn Professor of astronomy (A&S), who has been working on the Rover missions since he was a Cornell first-year student, is a co-investigator on Perseverance, working with their camera team to help cache samples for eventual return to Earth.
Weather on Mars fascinates Don Banfield, senior visiting scientist at CCAPS. As the lead on the suite of meteorological sensors on NASA’s INSIGHT Mars lander, he was instrumental in detecting dust devils – and then, with NASA’s Perseverance rover, recording their sound as they passed the Rover. Perseverance continues to bring Banfield, Hayes and other scientists rich new data on the red planet.
“Alone among the planets, Mars is the kind of place where you can imagine life taking hold and leaving behind traces of itself in the geologic record on the surface,” says Steven Squyres, ’78, Ph.D. ’81, the James A. Weeks Professor of Physical Sciences Emeritus (A&S) and principal investigator for NASA’s Mars Exploration Rovers. “Mars is a place that we can go to learn, perhaps, something about how life is born.”
Elsewhere in the solar system, Hayes will be taking to the skies of Saturn’s moon Titan in his co-investigator role on Dragonfly, a NASA rotorcraft mission to sample material and investigate the moon’s surface. The data will enable Hayes to explore questions about planetary surface processes and surface-atmosphere interactions.
“Solar system exploration allows us to study our own origins, from prebiotic chemistry, to understand how life emerged and evolved on Earth and whether it has emerged elsewhere, and to understand how the Earth formed – and how it might evolve in the future,” Hayes says.
Cornell scientists are also deeply involved with NASA’s Europa Clipper mission investigating the habitability of Jupiter’s moon. Astrobiologist Britney Schmidt, professor of astronomy (A&S) and of earth and atmospheric sciences in the Cornell Duffield College of Engineering, was involved in the mission’s early design and works with the spacecraft’s ice-penetrating radar instrument.
Schmidt’s lab is developing Icefin, an underwater robot to explore ocean worlds like Europa. The robots have already gathered first-of-its-kind data underneath glaciers, ice shelves and ice sheets in the Arctic and Antarctic. And their exploration of the unstable Thwaites glacier revealed crucial new information about the glacier’s melting speed and the condition of the Antarctic ice shelf. Now, they are working in Northwest Greenland to understand warming and ice loss there and test life detection strategies, funded by a major NASA astrobiology grant.
“This work is broader than what people think it is. It's not just stars and galaxies and telescopes. Our space research is going to help save the climate,” says Schmidt.
Solar system bodies, Hayes adds, “represent natural laboratories for studying extreme conditions that allow us to extrapolate the implications of climate change, what will happen, and whether the models are correct.”
The growing field of astrobiology has long been a fascination of Cornell astronomers dating back to Carl Sagan – from creative imaging of “life not as we know it” on Titan to “color catalogs” of biosignatures for exoplanets, with astronomers at Cornell using life science tools to search for life in the Solar System and beyond.
Astrobiologist Bonnie Teece, assistant professor of astronomy (A&S), was a key part of the Mars Sample Return mission formulations and studied both Mars and ocean worlds while at the Jet Propulsion Laboratory. At Cornell, she’s working to detect biosignatures on other worlds and finding ways to determine if geology is mimicking life.
Juno, another successful NASA planetary mission collaboration, is shedding light on the origin and evolution of Jupiter with the help of Jonathan Lunine, the David C. Duncan Professor in the Physical Sciences Emeritus (A&S). He’s a co-investigator on the mission and was a co-author on the surprising discovery of high-altitude lightning in Jupiter’s atmosphere.
Cornell planetary scientists have been recognized with numerous awards, including the American Astronomical Society’s Gerard P. Kuiper Prize, given to both Carl Sagan and Joseph Veverka. Veverka was the principal investigator on the NASA Comet Nucleus Tour mission and NASA’s Stardust-NeXT, which studied comets and asteroids.
The James Webb Space Telescope has been a boon for Cornell’s planetary and exoplanet researchers. Nikole Lewis, associate professor of astronomy (A&S), is principal investigator of a JWST team investigating the TRAPPIST-1 and several other exoplanet systems. She and her team recently released the unexpected finding that TRAPPIST-1 e, an Earth-sized exoplanet 40 light years away, may have an atmosphere that could support liquid water on the planet’s surface.
Building on a legacy: the Carl Sagan Institute
Sagan’s legacy at Cornell lives on in the multi-disciplinary Carl Sagan Institute, founded in 2015 to find life in the universe, explore other worlds and carry Sagan’s vision into the future, says Kaltenegger, founding director and professor of astronomy (A&S).
“The search for life needs a team of experts in chemistry, astronomy, physics, ocean science, biology, geology, the humanities and more – people who are trained in many different ways, so we don't miss signs of life because we're thinking too narrowly,” Kaltenegger says. “Cornell has a big advantage, because Sagan already was working across disciplines, so people recognized its importance early.”
With the discovery of more than 6,000 exoplanets, planetary science and the search for habitable worlds is no longer limited to our solar system. Institute scientists focus their research on the solar system and on exoplanets; Kaltenegger and others are building a “forensic toolkit” to find life, including how to spot life in clouds or what the light fingerprints of purple bacteria would be on the numerous worlds circling red stars.
The search for life spans single cells to advanced civilizations; Institute members also collaborate with the SETI Institute and the Breakthrough Listen Project. “It was a strong interest of Carl Sagan’s and some of us have been collaborating since the 1990s,” says Cordes. “There is a strong connection between the pulsar work I have done at Cornell and SETI, namely characterization of the interstellar medium and its effects on radio signals.”
Cornell scientists will continue to ask the big questions that expand our understanding of the universe, building on the legacy of more than half a century of discovery. They’re inspired by the same excitement Sagan described in his book “Broca's Brain,” when he said that curiosity is an essential tool and that “understanding is a joy.”
Linda B. Glaser is news and media relations manager in the College of Arts and Sciences.
