The Center for Astrophysics | Harvard & Smithsonian (CfA) and the U.S. National Science Foundation's National Radio Astronomy Observatory (NSF NRAO) have announced a new collaboration to advance the Event Horizon Telescope (EHT) into space. This next-generation effort, called the Black Hole Explorer (BHEX) mission, aims to improve black hole imaging by combining ground-based radio antennas with a space-based telescope.

The EHT gained international acclaim in 2019 with the first-ever image of a black hole, followed by a 2022 image of the supermassive black hole at the center of the Milky Way. The BHEX mission will expand this work, enabling scientists to produce the most detailed images of black holes to date, including the elusive photon ring -- the light that orbits a black hole's edge before escaping.

"This collaboration with NRAO marks a significant step forward in our quest to understand the nature of black holes," said Dr. Michael Johnson, principal investigator for BHEX at the CfA. "By extending the EHT to space, we'll be able to study dozens of black holes and unravel the mysteries of how they power the brightest engines in the universe."

The partnership, officially launched this month, focuses on integrating space-based observations with NRAO's advanced ground-based facilities, such as the NSF Green Bank Telescope (GBT), the Atacama Large Millimeter/submillimeter Array (ALMA), and the proposed Next Generation Very Large Array (ngVLA). These facilities will serve as ground anchors for the BHEX space-VLBI (Very Long Baseline Interferometry) mission, offering unprecedented resolution in black hole studies.

"NRAO leads and operates some of the most sensitive radio observatories in the world, making for a perfect partnership with the CfA to make this hybrid radio observatory happen," said Sara Issaoun, a Submillimeter Array Fellow at the CfA and the BHEX Science Operations Lead. "By combining space-based and ground-based observations, we'll be able to achieve unprecedented resolution and gain new insights into these cosmic phenomena."

The partnership aims to foster collaboration, resource sharing, and technical innovation between the CfA and NSF NRAO. It also includes efforts to upgrade ground-based instruments and infrastructure to support the mission's ambitious goals.

Dr. Tony Beasley, director of the NSF NRAO, highlighted the mission's potential: "With the support of the NSF and administration from Associated Universities, Inc., NRAO can position itself as a major partner in the ground network of this unique hybrid observatory."

"The Center for Astrophysics aims to answer humanity's unresolved questions about the universe. Every day, our scientists are pushing the envelope on what's possible," said Dr. Lisa Kewley, director of the CfA. "We look forward to working with NRAO as longtime leaders in radio astronomy. With this new partnership, together we will redefine the boundary of our knowledge about black holes."

The NSF NRAO will also lead discussions with international partners, including ALMA collaborators, to expand the mission's global reach. The partnership will set the stage for a new era in black hole imaging and astrophysical discovery by combining resources and expertise.