The American Astronomical Society (AAS) congratulates astrophysicists Roger Penrose (University of Oxford), Reinhard Genzel (Max Planck Institute for Extraterrestrial Physics & University of California, Berkeley), and Andrea Ghez (University of California, Los Angeles) for being named recipients of the Nobel Prize in Physics 2020. The Royal Swedish Academy is awarding half the $1.2 million prize to Penrose “for the discovery that black hole formation is a robust prediction of the general theory of relativity” and the other half jointly to Genzel and Ghez “for the discovery of a supermassive compact object at the center of our galaxy,” known as Sagittarius A* (abbreviated Sgr A*).

As noted by the Royal Swedish Academy, the “Laureates share this year’s Nobel Prize in Physics for their discoveries about one of the most exotic phenomena in the universe, the black hole. Roger Penrose showed that the general theory of relativity leads to the formation of black holes. Reinhard Genzel and Andrea Ghez discovered that an invisible and extremely heavy object governs the orbits of stars at the center of our galaxy. A supermassive black hole is the only currently known explanation.”

Genzel and Ghez are longtime members of the AAS and have been recognized by the Society for their ground-breaking research repeatedly over the years. In 1986 the AAS awarded Genzel its Newton Lacy Pierce Prize for outstanding achievement in observational astronomical research. Ghez received the same prize in 1998, four years after being awarded the Annie Jump Cannon Award for outstanding research and promise for future research. And when the Society named its first class of AAS Fellows in early 2020, Ghez was among the honorees.

“I am so delighted that our members Reinhard Genzel and Andrea Ghez are being recognized for their pioneering work on black holes,” says AAS President Paula Szkody (University of Washington). “I remember the amazement I felt about 20 years ago when I first saw the movie from Andrea’s team showing the motions of stars orbiting Sgr A* and providing the first good estimate of the supermassive black hole’s mass. The work of both Andrea’s and Reinhard’s teams to refine the star’s orbits and the black hole’s mass over the ensuing two decades is an inspiration to all of us on how to accomplish the best science with advanced telescopes.”

AAS Executive Officer Kevin B. Marvel notes that several of the landmark scientific articles featuring results from both teams have appeared in the Astrophysical Journal and the Astrophysical Journal Letters, the Society’s flagship peer-reviewed publications — as has been true of research for which several earlier Nobel Prizes have been awarded. “We are honored and thrilled to have such important work appear in our titles,” he says. “And it’s remarkable and satisfying that in three of the last four years the Nobel Prize in Physics has gone to scientists — often AAS members — working in astronomy and cosmology.”