Scientists Discover Fast-Growing Galaxies From Early Universe
A team of astronomers discovered a new kind of (old) galaxy. Formed less than a billion years after the Big Bang, the galaxy creates stars a hundred times faster than the Milky Way.
The discovery, which was published in the journal Nature, could help solve a puzzle scientists have been mulling over for generations: Why a mysterious population of massive galaxies appeared at a time when the universe was only 10 percent of its current age. A few years ago, astronomers propsed that these mysterious galaxies were created from hyper-productive precursor galaxies. It was the only way to explain how massive numbers of stars managed to form quickly. However, the team led by Max Planck Institute of Astronomy's Roberto Decarli discovered the increasing star population by accident while they were investigating quasars.
Quasars, as explained by Phys.org, are supermassive black holes that are sitting at the center of enormous galaxies. They are thought to form in regions where large-scale density of matter is higher than average. This is not the case for the team's study, though.
"But what we found, in four separate cases, were neighboring galaxies that were forming stars at a furious pace, producing a hundred solar masses' worth of new stars per year," Decarli explained.
However, whether or not these fast-growing galaxies are indeed precursors to more massive galaxies seen from a few years back could require more research, Eduardo Bañados, co-author of the study from the Carnegie Institute for Science, explained.
Follow-up investigations are already planned to explore the source of such galaxies, led by Decarli's team. Among the things found by the researchers included what appears to be the earliest known example of galaxies undergoing a merger -- another indication for galaxy growth. These observations provided direct evidence that mergers have and can take place even at the early stages of galaxy evolution.