SPIRAL GALAXY

The spiral galaxy UGC 2885, also called Rubin's Galaxy, is something of a local legend. At 232 million light years away, it is the largest galaxy known in our nearby universe, spanning more than twice the width of the Milky Way and containing 10 times as many stars. But astronomers aren't sure how it got so large. Galaxies typically grow by consuming or smashing into other galaxies. But UGC 2885 is alone in space, apparently having undergone neither process to gain its heft. Instead, researchers believe it may have grown by calmly siphoning gas from intergalactic space. One way to read the galaxy's past is to study the globular clusters of stars around it. These clusters often survive collisions and assimilations, revolving around the final result. Astronomers are now looking to count up the the globular clusters around UGC 2885 to see whether it has more than it should, which would hint that it's eaten other galaxies in the past.