These galaxies are no more seen in galaxy clusters in which they used be seen earlier, but are now leading a lonely future said Igor Chilingarian, the astronomer at Harvard- Smithsonian Center for Astrophysics and Moscow State University. If the escape velocity of runaway stars is faster than that of the parent galaxy, then they can be booted from home galaxies. The typical speed is 537 km/second and 1.2 million miles per hour.
This discovery is made special because entire galaxies that were marooned in space were found by scientists instead of just runaway stars that are very common. As such, these galaxies have to travel very fast so that they leave their galaxy cluster. The speed of these galaxies can reach up to 6million mph or 3000km/s based on the mass of the cluster.
Ivan Zolutukhin and Chilingarian reviewed public data from the Sloan Digital Sky Survey and GALEX Satellite with regards to compact elliptical galaxies. Zolotukin explained that “The first compact Ellipticals were all found in clusters because that’s where people were looking. We broadened our search, and found the unexpected,”.
It is tough to find such elliptical galaxies, but around 200 new compact Ellipticals were found by these 2 men out of which classification of 11 was done as runaway or homeless galaxies.
Scientists found that the speed of these galaxies is ridiculous and that the reason for them being booted out from clusters is due to similar factors that lead to creation of runaway stars.
“We asked ourselves, what else could explain them? The answer was a classic three-body interaction,” he remarked.
The study has been published in the journal Science.
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