Searching for Dwarf Galaxies and Big Waves – Marla Geha

Marla Geha is the co-chair of the Milky Way and Local Volume Structure science collaboration with Beth Willman. This collaboration’s primary science goals are to map the main components of the Milky Way, to find small dwarf galaxies orbiting the Milky Way, and to trace out any lumpiness or substructure in the Milky Way that can provide evidence of dwarf galaxy satellites destroyed by its gravity. Accomplishing these goals will require data across the full sky.

“LSST’s camera has a large field of view and by stitching together many of these images, we hope to reconstruct the Galaxy in which we live.

“Data from LSST will answer a wide variety of scientific questions. Usually astronomical data are taken with a very specific purpose in mind, which often can’t be used to answer other astronomical questions. LSST will serve so many different purposes. This allows for conversations among people in different sub-disciplines of astronomy that normally don’t have much to say to each other. The LSST All Hands Meeting in August 2010 was a great example of this – terrific energy and interaction in one room.

“My own interest in LSST is in finding the faintest satellite galaxies orbiting the Milky Way. Before 2005 the eleven satellite galaxies known were thought to be the Milky Way’s only companions. The Sloan Digital Sky Survey, the first digital mapping of the full sky, has discovered an additional fourteen, and many more are expected. These new dwarf galaxies are ultra-faint, that is, several million times fainter than the Milky Way, and less luminous than any other known galaxy. Most of their mass is composed of dark matter – whatever it may be – and LSST will help find hundreds more of these elusive objects. In completing a census of satellites around the Milky Way, LSST will provide a more complete picture of the Milky Way neighborhood as well as finding new ‘laboratories’ in which we can study dark matter.”

Marla defines perhaps her biggest challenge as finding time for her research and excelling as a teacher: “being a professor is enjoyable but requires a lot of work – especially when you are the type of person who enjoys it and wants to do it right.” One of the courses that Marla teaches as an Assistant Professor at Yale University is a non-science major course, Frontiers of Astrophysics, which might have among its 80-100 students the future senators, decision makers, and corporate leaders who will affect research funding and national priorities. In some respects classes such as this may have greater impact on future science and technology success than those training scientists and engineers. Marla is acutely aware that it is critical to engage these students in the facts and process of science. She hopes to fold some of the LSST education and public outreach efforts into her classes.

Her career has taken Marla from a B.S. at Cornell University to an M.S. at New Mexico State University to a Ph.D. in Astronomy and Astrophysics at the University of California at Santa Cruz to researching and teaching at Yale University since 2008. Having won several prizes and fellowships, she was named one of Popular Science’s “Brilliant 10” in 2009. The only complaint she has about Yale’s location is the lack of surfing in Connecticut. Nevertheless, Marla is able to collaborate with several other surfing astronomers to find time to catch some big waves and produce outstanding science in other parts of the world.

By Anna H. Spitz with Marla Geha