Cal Tech Astronomers using the GALEX telescope, made a very interesting and unprecedented discovery of a massive tail being left in the trail of a well-known star, Mira. The faint tail, seen in ultraviolet light, spans more than 13 light years in the wake of Mira. The discovery of this phenomenon includes a ‘bow-shock’ ahead of the star, analogous to a vessel underway on the sea.
Mira, a late-sequence red-giant star, is shedding it’s outer layers as it hurtles through the universe at amazingly high speeds (relative to our Sun). As scientists study this interesting discovery, they are likely to learn more about the ultimate destiny of our own star, which, as we know, will be similar to Mira in about five billion years.
From Science@NASA:
August 15, 2007: Astronomers using a NASA space telescope, the Galaxy Evolution Explorer, have spotted an amazingly long comet-like tail behind a star streaking through space. The star, named Mira after the Latin word for “wonderful,” has been a favorite of astronomers for about 400 years, yet this is the first time the tail has been seen.
Galaxy Evolution Explorer–“GALEX” for short–scanned the popular star during its ongoing survey of the entire sky in ultraviolet light. Astronomers then noticed what looked like a comet with a gargantuan tail. In fact, material blowing off Mira is forming a wake 13 light-years long, or about 20,000 times the average distance of Pluto from the sun. Nothing like this has ever been seen before around a star.
NASA and JPL/Caltech prepared a half-minute animation which is an artist’s conception of Mira generating her tail. Be sure and watch this neat little video.
A close up view of the top of the Sun as seen in profile shows thousands of little spurts, like small blow torches, shooting out all over the Sun. The movie shows just an average day’s worth of this kind of activity as seen from the 
Using volumes of data from the Two-Micron All Sky Survey (2MASS), a major project to survey the sky in infrared light led by the University of Massachusetts, the astronomers are answering questions that have baffled scientists for decades and proving that our own Milky Way is consuming one of its neighbors in a dramatic display of ongoing galactic cannibalism. The study published in the Astrophysical Journal, is the first to map the full extent of the Sagittarius galaxy and show in visually vivid detail how its debris wraps around and passes through our Milky Way. Sagittarius is 10,000 times smaller in mass than the Milky Way, so it is getting stretched out, torn apart and gobbled up by the bigger Milky Way. 
Tomorrow night, when the full moon rises over North America, it is believed that this will be a “blue moon.” The modern definition for “blue moon” is the second full moon to occur within a calendar month and tomorrow’s full moon will indeed be the second to occur in the month of May, 2007.