Q4 Biography

Margaret Geller Bio 

     Margaret Geller, a magnificent American astronomer and professor, was born in 1948 to Seymour Geller and Sarah Levine Geller. The daughter of a crystallographer from Ithaca, New York State, Geller was encouraged as a small child to study science and mathematics. Her education includes a B.A from the University of California, Berkeley in 1970, a M.A from Princeton University in 1972, and a Ph.D. from Princeton University in 1974. After a period at the Institute of Astronomy, Cambridge, England, Geller moved to Harvard in 1980 and was appointed professor of astronomy in 1988.

     Since the early 1980s Geller and her coworkers have been carrying out for the Center for Astrophysics (CfA) a red-shift survey of some 15,000 galaxies. The intention is to map all galaxies above a certain brightness, out to about 650 million light years, in a particular sector of the heavens. They were aware that to some observers the sky lacked the uniformity predicted by the big-bang theory. In 1981, for example, a 100-million-light-year gap had been discovered in the constellation Bootes. Geller considered the possibility that this was a local phenomenon, and that the predicted homogeneity would become more apparent on a much larger scale. Further investigations were expected to show a uniform distribution of galaxies.

     But when they came to plot the distribution of galaxies they saw neither a uniform spread, nor a random scattering of galaxies, but large-scale clusters grouped into enormous structures. The largest of these, dubbed the Great Wall, stretches for more than 500 million light-years. It was difficult to see how anything as massive could have been formed within the context of current cosmological theory; when Geller reported the initial results of the CfA survey in 1989 she noted, “Something fundamental is missing in our models.”The existence of this structure, the largest ever seen in the universe, presents a conundrum for theorists dealing with the early universe. She has been mapping the nearby universe for the past sixteen years and has produced the most extensive pictures yet.

      She is also a staff member of the Smithsonian Astrophysical Observatory.She is interested in mapping the distribution of the mysterious, ubiquitous dark matter in the universe, the halo of our own galaxy, the Milky Way, to understand the link between the history of our Galaxy and the history of the universe. She does this by mapping clusters of galaxies to understand how these systems develop over the history of the universe, and measuring and interpreting the signatures of star formation in the spectra of galaxies to understand the links between the star formation in galaxies and their environment. She leads a program called SHELS.

     Geller won a MacArthur fellowship- also know as a "genius award" - in 1990 for her research. SHe received the Newcomb-Cleveland Prize of the American Academy of Arts and Sciences that same year. In addition to galaxy distributions, Geller is interested in the origin and evolution of galaxies and X-ray astronomy. She is a member of the International Astronomical Union, the American Astronomical Society, and the American Association for the advancement of Science. 

APOD 4.7

The Sombrero Galaxy from Hubble

Named the sombrero galaxy for its hat-like resemblance, M104 features a prominent dust lane and a bright halo of stars and globular clusters. Reasons for its hat-like appearance include an unusually large and extended central bulge of stars, and dark prominent dust lanes that appear in a disk that we see nearly edge-on. Billions of old stars cause the diffuse glow of the extended central bulge. The very center of the Sombrero is thought to host a black hole! It's a really awesome picture to look at.

Margaret Geller Bio Sources

"ASP: Women in Astronomy: An Introductory Resource Guide to Materials in English."Astronomical Society of the Pacific. Web. 16 May 2011. <http://www.astrosociety.org/education/resources/womenast_bib04.html>.


Lawler, Andrew. "Margaret Geller: Battling Discrimination or Bureaucracy?" Science. American Association for the Advancement of Science, 12 Nov. 1999. Web. 16 May 2011. <http://www.sciencemag.org/content/286/5443/1277.short>.

"Margaret Geller's SAO Home Page." Margaret Geller. Web. 16 May 2011. <https://www.cfa.harvard.edu/~mjg/>.

APOD 4.6

Globular Cluster M15 from Hubble 

Stars swarm around the center of the bright globular cluster M15. This ball of over 10,000 stars is still here from the earliest years of our galaxy and continues to orbit the Milky Way's center. M15 is one of only 150 globular clusters remaining and can only be seen with binoculars. It's center has one the densest concentrations of stars known and contains a high abundance of variable stars and pulsars. This image was taken by the Hubble Space Telescope and spans about 120 light years.