Margaret Geller

Lore & Background

Margaret Geller earned a Bachelor of Arts in Physics from the University of California, Berkeley in 1970 and a Ph.D. in Physics from Princeton in 1974. Her doctoral dissertation, 'Bright galaxies in rich clusters: a statistical model for magnitude distributions,' was supervised by James Peebles. Charles Kittel suggested she go to Princeton to study astrophysics, though she had considered solid state physics. After research fellowships at the Center for Astrophysics | Harvard & Smithsonian and the Institute of Astronomy in Cambridge, England, she became an assistant professor of Astronomy at Harvard University from 1980 to 1983, then joined the permanent scientific staff of the Smithsonian Astrophysical Observatory.

In the 1980s, Geller made pioneering maps of the nearby universe that included the Great Wall. Her SHELS (Smithsonian Hectospec Lensing Survey) maps dark matter distribution, and she leads the deeper HectoMAP survey of the middle-aged universe using the 6.5-m MMT. She is also a co-discoverer of hypervelocity stars. Geller has made public education films, including 'Where the Galaxies Are' (1989), which won a CINE Gold Eagle, and 'So Many Galaxies...So Little Time,' which received an IEEE/Siggraph prize and was displayed at the National Air and Space Museum.

Reader's Guide

Margaret Geller's significance lies in her pioneering observational and theoretical work in cosmology and extragalactic astronomy. Her maps of large-scale structure, particularly the Great Wall, fundamentally changed understanding of the universe's organization. Her long-range goal—to discover what the universe looks like and how observed patterns evolved—has driven innovative techniques for investigating galaxy clusters and their surroundings. The SHELS and HectoMAP surveys continue to advance knowledge of dark matter distribution. Her co-discovery of hypervelocity stars provides a new tracer of matter in the Galaxy. Geller's public engagement, including award-winning films and lectures, has made cosmology accessible to broad audiences. Her election to the National Academy of Sciences and receipt of numerous honors, including the MacArthur Fellowship and the James Craig Watson Medal, underscore her lasting impact on astrophysics.

Did You Know?

• Geller's pioneering maps of the nearby universe included the Great Wall.
• She is a co-discoverer of hypervelocity stars, which may trace matter distribution in the Galaxy.
• Her 8-minute video 'Where the Galaxies Are' (1989) won a CINE Gold Eagle and was an early visualization of the observed universe.
• She received a MacArthur Foundation Fellowship in 1990.