Astronomers locate 11 Galaxies facing Lonely Future

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It’s a first for researchers to have discovered a number of runaway galaxies that managed to find a place away from their original homes. The galaxies have been thrown away from their galactic clusters because of gravitational turbulence. Discovery News has reported that 11 homeless galaxies have been identified by Igor Chilingarian, an astronomer at the Harvard-Smithsonian Center for Astrophysics, and Moscow State University, and his fellow astronomers.
They stumbled upon the discovery while reviewing publicly available data collected by the Sloan Digital Sky Survey and the GALEX satellite for compact elliptical galaxies.
“These galaxies are facing a lonely future, exiled from the galaxy clusters they used to live in”, said Chilingarian. Findings of the new discovery have been published in the paper in the journal Science.
Chilingarian and Zolotukhin said that their original goal was to identify new members of a class of galaxies known as compact elliptical. These are small groups of stars larger then star clusters, but not larger than typical galaxies. They managed to identify nearly 200 previously unknown compact ellipticals. Of them, 11 were lonely and were located at a good enough distance from any clusters.
The discovery left the researchers surprised, given the previous elliptical that had been found were all located in clusters. The newly found galaxies were learnt not to be isolated only, but moving at a pace faster than those in clusters.
The researchers were of the belief that the reason behind the small size of these galaxies was them being stripped of their stars by other larger galaxies.
According to Chilingarian and Zolotukhin, an object becomes a runaway after attaining traveling speed faster than escape velocity, which does not allow it to ever return to its place of origin.