Observing Galaxies with the Green Bank Telescope 

Students in Professor John Cannon’s Observational Astronomy course recently spent an afternoon working with the Green Bank Telescope—the largest fully steerable radio telescope in the world. Standing over four hundred eighty feet tall and weighing nearly seventeen million pounds, it is the foremost instrument with which to study the global physical properties of galaxies. Students actively observed nearby galaxies with the GBT, and after the observing session, they processed the data to determine the mass and velocity of neutral hydrogen gas in each of the target galaxies. “The GBT is one of the most sophisticated scientific instruments in the world,” says Cannon. “For students at a liberal arts college to be able to use such an instrument in a classroom setting is truly remarkable. In this case, the student experience went light years beyond the typical bounds of a classroom—providing a glimpse into how professional astronomers acquire and use observational data to further our understanding of the cosmos.”