For 10 points, name this galaxy, which contains the only planet known to support life, Earth.
In 2003, a satellite of this object, "Complex H," was discovered to have a retrograde orbit, and in 2006, University of California at Berkeley researchers found that a "warp" in this object is vibrating with three modes. Its center is inhabited by the supermassive black hole candidate Sagittarius A* ("a star").  The Canis Major Dwarf Galaxy is its nearest neighbor, and it also interacts with the nearby Large and Small Magellanic Clouds. For 10 points, name this galaxy, which contains the only planet known to support life, Earth.
In 2003, a satellite of this object, "Complex H," was discovered to have a retrograde orbit, and in 2006, University of California at Berkeley researchers found that a "warp" in this object is vibrating with three modes.
{Milky Way} Galaxy