#January2011

Milky Way Galaxy May Be Surrounded By Dark Matter Galaxies. Wut?

Speculative science is awesome. Especially if you’re into theorizing and not, you know, hardcore facts. This seems to always be the case when talking about sweet-ass outer-space things. You know. Black holes, dark matters. That sort of swag. Well today, we have this wonderful little teaser: is the Milky Way Galaxy surrounded by invisible dark matter galaxies? Dun, dun, dun!

Alasdair Wilkins over at io9 brings the interesting article to the forefront, and this is the dealio. Based on how gravity affects gases at the edge of the Milky Way, we should have  a satellite galaxy located 26,000 light-years away. The problem? We ain’t never seen that thang. Wilkins elaborates:

Astronomer Sukanya Chakrabarti looked for gravitational effects created by potential satellite galaxies of our home, the Milky Way. Not unlike the gas giants such as Jupiter of Saturn, the Milky Way has a bunch of relatively tiny “moon” galaxies. The most famous of these, the Magellanic Clouds, are about 10 percent the size of our galaxy, but most of these satellite galaxies are less than a hundredth the size of the Milky Way.

Back in the 19th century, astronomers detected the planet Neptune by observing the slight gravitational wobble of Uranus, which could only be caused by an undetected planet further out. The same basic principle is at work here, as this mysterious Galaxy X is creating movement in the gas at the edge of our galaxy. Chakrabarti suspects the galaxy is composed mostly of dark matter, which is part of the reason why we hadn’t found it up to this point.

If it exists, Galaxy X would be about 1% the size of the Milky Way, making it the third largest satellite after the Magellanic galaxies. While dark matter would make up most of its mass, there would likely still be some dim stars of regular matter in there as well. The galaxy lies on the same plane as our galactic disc, meaning astronomers need to look through all the bright lights of the Milky Way just to see Galaxy X. Still, now that we know where to look, Chakrabarti says, we should be able to find it.

A dark matter galaxy! Interesting shit. I wonder what our dark matter companions are up to? Are they fans of sports? What sort of thing turns them on? Read more.