How a ‘mundane’ galaxy could offer insights into the evolution of the universe
NASA and the European Space Agency have unveiled a photo taken by the Hubble Space Telescope of a small irregular galaxy that initially appeared unremarkable. However, further analysis reveals a complex structure in NGC 5238, located 14.5 million light-years away in the Canes Venatici constellation. Scientists are conducting extensive research on the galaxy, suspecting that its star distribution may have been altered due to a past merger with another galaxy.
They estimate that due to the stellar population of NGC 5238 (which Hubble is adept at helping to image), it had a “close encounter” with another galaxy perhaps as much as a billion years ago. But since the galaxy is not close enough to have distorted the distribution of stars in this way, it is more likely that NGC 5238 merged with a smaller galaxy. In addition to many stars, the galaxy has globular stars, which NASA describes as “shiny, bright spots both within and around the galaxy, teeming with even more stars.”
Astronomers plan to dig deep into the data to learn about NGC 5238’s past. If they find clusters of stars that have different properties than most other stars in the galaxy, that’s a clear indication that a merger has occurred. They are also trying to determine whether there was a “burst of star formation” that occurred suddenly after the galaxies had merged.
NASA points out that an irregular dwarf galaxy merging with a smaller satellite galaxy is exactly the kind of thing that could have fueled galaxy formation in the early ages of our universe. As such, the agency says the data collected by Hubble on NGC 5238 can help scientists test fundamental ideas about the evolution of the universe.
