Post by glactus on Jul 23, 2009 2:44:57 GMT
CL0958 + 4702 merger
Four galaxies are slamming into each other and kicking up billions of stars in one of the largest cosmic smash-ups ever observed.
The clashing galaxies, spotted by NASA's Spitzer Space Telescope, will eventually merge into a single, behemoth galaxy up to 10 times as massive as our own Milky Way. This rare sighting provides an unprecedented look at how the most massive galaxies in the universe form.
The new quadruple merger was discovered serendipitously during a Spitzer survey of a distant cluster of galaxies, called CL0958+4702, located nearly five billion light-years away.
The infrared telescope first spotted an unusually large fan-shaped plume of light coming out of a gathering of four blob-shaped, or elliptical, galaxies. Three of the galaxies are about the size of the Milky Way, while the fourth is three times as big.
Further analysis of the plume revealed it is made up of billions of older stars flung out and abandoned in an ongoing clash. About half of the stars in the plume will later fall back into the galaxies. "When this merger is complete, this will be one of the biggest galaxies in the universe..
Some of the stars tossed out in the monstrous merger will live in isolated areas outside the borders of any galaxies. Such abandoned stars could theoretically have planets. If so, the planets' night skies would be quite different from our own, with fewer stars and more visible galaxies.
Credits: this is a NASA /JPL image