NASA and the European Space Agency have posted a picture The Hubble Space Telescope has captured an image of an irregular dwarf galaxy that, it admits, looked “uninteresting” at first glance. However, there is more going on than meets the eye. Agencies say that a lot of research is being done into the “complicated structure” of NGC 5238, which lies 14.5 million light-years away in the constellation Canes Venatici. In fact, astronomers believe that the distribution of stars in NGC 5238 may have become distorted after it swallowed another galaxy.
Astronomers believe that because of NGC 5238's population of stars (which Hubble is adept at helping to image), it had a “close encounter” with another galaxy perhaps a billion years ago. But since there's no galaxy nearby enough to have distorted the star distribution in this way, it's more likely that NGC 5238 merged with a smaller galaxy. In addition to being home to plenty of stars, the galaxy is home to globular clusters, which NASA describes as “bright, glowing points both within and around the galaxy, surrounded by even more stars.”
Astronomers plan to dig deeper into the data to learn about NGC 5238's past. If they find star clusters that have different properties than most other stars in the galaxy, that will be a clear indication that a merger has occurred. They will also try to determine if there was a “burst of star formation” that occurred suddenly after the galaxies had merged.
NASA says a dwarf irregular galaxy merging with a smaller satellite galaxy is just the kind of phenomenon that could have driven galaxy formation in the early era of our universe. The agency says the data Hubble captured of NGC 5238 can help researchers test fundamental ideas about the evolution of the universe.
