The biggest space collision ever

Aug 9, 2007 09:28 GMT  ·  By
An artist's rendering shows what the night sky might look like from a hypothetical planet near the ongoing four-way collision recently observed by NASA's Spitzer Space Telescope
   An artist's rendering shows what the night sky might look like from a hypothetical planet near the ongoing four-way collision recently observed by NASA's Spitzer Space Telescope

Milky Way is so small after all since the largest star collision ever seen took place. A new galactic war gave birth to a new galaxy which will be ten times bigger than the Milky Way.

The galactic crash was spotted by astronomers using NASA's Spitzer Space Telescope and Kenneth Rines said that "this is a very unusual case," because "it's a first to have four galaxies merging."

Galactic mergers are fairly common, explained Rines. Most cosmic crashes involve two galaxies of similar size or smaller galaxies coalescing into a larger one. What makes this event unique is the sheer size and number of galaxies involved, Rines said. It was the first time when four galaxies merged into one and the size of the three is absolutely impressive: three of the star systems are about the size of the Milky Way and the fourth is three times larger.

"Another unique aspect of the merger is the apparent lack of new stars being formed", said Rines.

Typically, when galaxies converge, the intervening gas clouds compress and begin to form stars, he explained. But scientists have not detected gas clouds in the four galaxies, which means no new stars will be born from the merger.

This megacollision will help scientists learn more about how large galaxies are formed. "This merger tells us that you can make a clear distinction between when a star in a galaxy forms and when the galaxy itself assembles," he said. In this case, all of the stars had formed before the merger. "But if you had just looked at the star age once the new galaxy is fully formed , you would have assumed the galaxy is much older than it really is," he noted.

Since these four galaxies need a hundred million years to finally become one, we can hope for the best. Happy many returns of the day!