That's no comet...

Traveling 80 miles per second, this star is leaving a trail behind, like a comet.

Well, that's not a comet, it's actually the star Mira, moving so fast through interstellar space that it's leaving a tail behind.
Mira is an older, red giant star shedding massive amounts of material into space. As the star moves quickly through interstellar space, the particles slow down, and remain as a long tail stretching behind. In fact, this tail is 13 light-years long, or 20,000 times the average distance of Pluto from the Sun.

The image was captured by NASA's Galaxy Evolution Explorer satellite, and the researchers announced their findings during a NASA press conference today. Their research will be published in the latest issue of the journal Nature.