Cambridge, MA -
The National Science Foundation has just announced the award of a $12.7M grant to architect and design a next-generation Event Horizon Telescope (ngEHT) to carry out a program of transformative black hole science.
Led by Principal Investigator Shep Doeleman at the Center for Astrophysics | Harvard and Smithsonian (CfA), the new ngEHT award will fund design and prototyping efforts by researchers at several US institutes. These include Dr. Gopal Narayanan at University of Massachusetts, Amherst, Dr. Vincent Fish at the MIT Haystack Observatory, and Drs. Katherine L. (Katie) Bouman and Gregg Hallinan at Caltech. At the CfA, Drs. Michael Johnson, Jonathan Weintroub and Lindy Blackburn are co-Principal Investigators of the ngEHT program.
On April 10th, 2019, the International Event Horizon Telescope Collaboration released the first image of a supermassive black hole. A bright ring of emission at the heart of the Virgo A galaxy revealed a black hole, known as M87, that has the mass of 6.5 billion Suns. Einstein’s theory of gravity passed this new test in spectacular fashion in this extreme cosmic laboratory. For this work, the EHT Collaboration will receive the Breakthrough Prize in Fundamental Physics this November.
Black holes, objects with gravity so strong that light cannot escape, are now accessible to direct imaging. More precise tests of gravity can now be contemplated, and the processes by which supermassive black holes energize the brightness and dynamics of most galaxy cores can be studied in detail. The next-generation EHT (ngEHT) will sharpen the focus on black holes, and let researchers move from still-imagery to real-time videos of space-time at the event horizon.
"As with all great discoveries, the first black hole image was just the beginning," says Doeleman, Founding Director of the EHT. "Imagine being able to see a black hole evolve before your eyes. The ngEHT will give us front-row seats to one of the Universe's most spectacular shows."
Sparked by this major investment, the ngEHT is expected to attract additional international support and participation by the broad EHT community. The ngEHT award is aimed at solving the formidable technical and algorithmic challenges required to significantly expand the capability of the EHT.
The first M87 black hole images were made using the technique of Very Long Baseline Interferometry (VLBI), in which an array of radio dishes around the world is combined to form an Earth-sized virtual telescope. By exploring new dish designs and locations, the ngEHT effort will plan the architecture for a new array with roughly double the number of sites worldwide.
"The EHT observations demand unusually dry atmospheric conditions typically found at high altitudes. Identifying sites that meet this demand and deploying new dishes will vastly improve the EHT array's black hole imaging ability," says Dr. Jonathan Weintroub.
In addition to new dishes, the ngEHT will incorporate an existing telescope at Caltech's Owen’s Valley Radio Observatory (OVRO) and will upgrade the Large Millimeter Telescope Alfonso Serrano (LMT) in Mexico. "With its large aperture and central geographic location, the LMT is crucial to the next generation EHT effort. Planned enhancements to the LMT’s performance using MSRI funds will improve the EHT sensitivity over long observing campaigns," notes Dr. Gopal Narayanan.
New technologies will, in turn, allow the ngEHT to expand the swath of radio frequencies it uses to photograph the event horizon. High speed recording systems that capture radio waves from the black hole will transfer data to central locations where they can be merged in a process that is analogous to the mirror in an optical telescope reflecting light to a single focus.
"Currently, the EHT records about 10 PetaBytes of data each session," according to Dr. Vincent Fish. "With planned higher data rates and the inclusion of new observatories, EHT data volumes could exceed 100 PetaBytes. Part of this project will be to investigate how to leverage advances in commercial technology to cost-effectively record and transport such a large volume of data."
The process of combining and analyzing data from around the globe demands high-performance computers and software that align signals from each EHT site to a fraction of a trillionth of a second. "The ngEHT pushes the boundaries in VLBI data complexity, along with the demands of models that seamlessly link the antennas together into a single Earth-size telescope," says Dr. Lindy Blackburn.
By filling in the Earth-sized lens with many new geographic locations, the ngEHT program will be able to harness new powerful algorithms to turn the incredible data volumes into images and even movies.
"Our own Milky Way is host to a supermassive black hole that evolves dramatically over the course of a night. We are developing new methods, which incorporate emerging ideas from machine learning and computational imaging, in order to make the very first movies of gas spiraling towards an event horizon," says Dr. Katie Bouman
The goal of the EHT is to address some of the greatest mysteries and deepest questions about black holes.
"Despite decades of study, some of the most basic questions about black holes remain untested," says Dr. Michael Johnson. "With the ngEHT, we will be able to study how black holes act as powerful cosmic engines, energizing a swirling bath of infalling plasma and efficiently pouring unimaginable amounts of energy into narrow jets that pierce entire galaxies.”
Doeleman is optimistic about the prospects of new discoveries with the ngEHT. "A decade ago we predicted we would be able to see a black hole. Now we estimate that over a billion people have seen the first image, and the Breakthrough Prize shows the impact it is having across the sciences. Through the ngEHT we are setting our sights high again, aiming to bring humanity even closer to the event horizon."
Learn more here: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1935980
Headquartered in Cambridge, Mass., the Center for Astrophysics | Harvard & Smithsonian (CfA) is a collaboration between the Smithsonian Astrophysical Observatory and the Harvard College Observatory. CfA scientists, organized into six research divisions, study the origin, evolution and ultimate fate of the universe.
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Center for Astrophysics | Harvard & Smithsonian