The Andromeda galaxy’s violent past has been revealed courtesy of a new study, and in the process it has basically been revealed that it’s just a plain old bully.
Astronomers have revealed that over the last million or so years, the galaxy has been consuming and absorbing weaker galaxies and their content before then moving on as if nothing had happened.
According to UPI, scientists were able to reach this conclusion after they conducted an extensive survey and analysis of Andromeda’s movement and population. Andromeda’s movement suggested a turbulent and violent past, which had watched it ingest and conquer smaller galaxies that were in its way.
This information was gathered as part of the Panchromatic Hubble Andromeda Treasury survey. Alongside employees at W.M. Keck Observatory in Hawaii and the Hubble Space telescope, PHAT has collected extensive images of Andromeda’s stellar population
After looking at these pictures, those involved in the study soon deciphered that there was a huge difference between the movement of the galaxy’s older collection of stars and its younger counterparts.
Sci-News reported that Professor Puraga Guhathakurta, who is the co-author of the study and works at the University of California, Santa Cruz, explained that this research gave scientists greater perspective on how to view the Milky Way.
“In the Andromeda galaxy we have the unique combination of a global yet detailed view of a galaxy similar to our own. We have lots of detail in our Milky Way, but not the global, external perspective.”
Meanwhile Claire Dorman, a graduate student at the University of California and a lead author on the project, explained what the images from Hubble consisted of.
“The high resolution of the Hubble images allows us to separate stars from one another in the crowded disk of Andromeda, and the wide wavelength coverage allows us to subdivide the stars into sub-groups according to their age.”
Dorman added that in comparison to the history of our own galaxy, the Milky Way, Andromeda has had a much more “violent” past.
“The comparison to the Milky Way revealed substantial differences suggesting that Andromeda has had a more violent accretion history in the recent past.”
The difference between the older and newer stars in Andromeda’s galaxy has, for now, been blamed on its violent past. However, scientists want to conduct more research to actually confirm their findings.
They also believe that Andromeda’s past might be the normal history of a galaxy, and in fact they are confident that the Milky Way’s quieter past is the rarity.
[Image via NASA]