An Indian Catholic priest and astrophysics researcher found conclusive evidence of a long lost galaxy, the third largest after Andromeda and the Milky Way. Fr D’Souza said that people had already given up on this and had moved to other problems. They kept plodding along, and finally, they had a breakthrough. From here they realized that they had to abandon so many things that they thought they knew.
A galaxy like Andromeda was expected to have engulfed hundreds of its smaller companions. The researchers thought that this would make it more difficult to learn about any single one of them. More importantly, this discovery and the method will now pave the way for the discovery of other galaxies that have been engulfed by other larger galaxies.
Using new computer programs, the scientists were able to understand that even though many companion galaxies were engulfed by Andromeda, most of the stars in the Andromeda are contributed by shredding a single large galaxy.
D’Souza, a Jesuit priest who is from Goa’s Mapusa town and is a staff astronomer of the Vatican Observatory in Rome, is currently pursuing his post-doctoral research at the University of Michigan’s Department of Astronomy.
He along with fellow researcher Eric Bell hit upon convincing evidence of galaxy named M32p that was “tattered and cannibalized” by the Milky Way’s galactic neighbor Andromeda about two billion years ago.
This distributed galaxy was the third-largest member of the local group of galaxies, after the Milky Way and Andromeda galaxies. Using computer models, D’Souza and Bell were able to piece together this evidence, discovering this long-lost sibling. Their discovery was published in Nature Astronomy earlier this month.
Discovering and studying this engulfed galaxy will help the astronomers understand how disk galaxies like the Milky Way evolve and survive large mergers?
Their discovery could alter the traditional understanding of how galaxies evolve. The two scientists realized that Andromeda’s disk survived an impact with a massive galaxy, which would question the common knowledge that such large interactions would destroy disks and form an elliptical galaxy.
The timing of the merger also explains the thickening of the disk of the Andromeda galaxy as well as a burst of star configuration two billion years ago, a finding which was separately reached by French researchers earlier this year