Awesome, just awesome.
"Based on how gravity affects the gases at the edge of our galaxy, we should have a satellite galaxy located about 26,000 light-years away...except nobody's ever seen it. This might be because it's composed almost entirely of dark matter.
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" See the rest HERE