At the center of most galaxies lies a supermassive black hole-a powerful beast millions to billions of times more massive than the Sun. One of the primary processes thought to be responsible for a sudden halt in star formation inside a merged galaxy is an overfed black hole. Red corresponds to 8.0 microns, a wavelength mostly emitted by dust. Blue corresponds to 3.6 microns, and green corresponds to 4.5 microns-both strongly emitted by stars. In these images, different colors correspond to different wavelengths of infrared light, which are not visible to the human eye. The images above show three of those targets, imaged by Spitzer. The survey has focused on 200 nearby objects, including many galaxies in various stages of merging. For more than 10 years, scientists working on the Great Observatories All-sky LIRG Survey, or GOALS, have been using nearby galaxies to study the details of galaxy mergers and to use them as local laboratories for that earlier period in the universe's history. Only a few percent of galaxies in the nearby universe are merging, but galaxy mergers were more common between 6 billion and 10 billion years ago, and these processes profoundly shaped our modern galactic landscape.