Interestingly, the stars are not attached to any galaxy

Jun 5, 2015 09:31 GMT  ·  By

Not long ago, between 2008 and 2010, the Canada-France-Hawaii Telescope on the slopes of the Mauna Kea mountain on Hawaii's Big Island spotted three stars exploding in the distant cosmos. 

At that time, however, astronomers couldn't quite figure out whether the stars were part and parcel of a faint galaxy or if maybe they were castaways. Well, leave it to the Hubble Space Telescope to clear up this conundrum.

Pinning down cosmic refugees 

In a recent study, University of California, Berkeley researcher Melissa Graham and colleagues turned to the NASA/ESA instrument to have another look at the supernovae and found them to be completely isolated in space.

Further, the astronomers argue that, judging by how far they are from any galaxy, these orbs were likely chased away from their homes millions if not billions of years before they exploded into supernovae.

Based on data delivered by the Hubble Space Telescope, the team theorizes that, when they reached the end of their life and went kaboom, the stars were about 300 light-years away from their nearest companion.

Just to put things into perspective, the astronomers go on to detail that the distance between our Sun and its nearest stellar companion is one of approximately 4.2 light-years.

Supposing that these stars had any planets orbiting them, the orbs were undoubtedly obliterated when the fiery celestial bodies exploded. Let's just hope there were no aliens on them.

Why bother to study castaway stars?

Just like individual stars, galaxies like to hang out in clusters. It is estimated that, due to gravitational interactions, galaxies positioned in massive clusters eventually lose about 15% of their stars, which migrate to intra-cluster regions.

Since they are all alone, these refugees don't appear all that bright and are, therefore, tricky to spot. As explained by Melissa Graham and fellow researchers, they only get noticed when they explode in supernovae.

The reason astronomers search for such exploding orbs in the otherwise empty space in between galaxies is that they expect that this will lead them to a better understanding of the formation and the evolution of the cosmos.

“Such rare solitary supernovae provide an important clue to what exists in the vast empty spaces between galaxies, and can help astronomers understand how galaxy clusters formed and evolved throughout the history of the universe,” the scientists explain.