Mira's tail also tells a tale of its history - the material making it up has been slowly blown off over time, with the oldest material at the end of the tail being released about 30,000 years ago (figure 2).
For comparison, the nearest star to our sun, Proxima Centauri, is only about 4 light-years away. Mira's comet-like tail stretches a startling 13 light-years across the sky. When astronomers first saw the picture, they were shocked because Mira has been studied for over 400 years yet nothing like this has ever been documented before. The Galaxy Evolution Explorer discovered the strange tail during part of its routine survey of the entire sky at ultraviolet wavelengths. The large blue dot on the left side of the upper panel, and the large yellow dot in the lower panel, are both stars that are closer to us than Mira. The dots in the picture are stars and distant galaxies. The close-up picture at bottom gives a better look at Mira itself, which appears as a pinkish dot, and is moving from left to right in this view. In figure 1, the upper panel shows Mira's full, comet-like tail as seen only in shorter, or "far" ultraviolet wavelengths, while the lower panel is a combined view showing both far and longer, or "near" ultraviolet wavelengths. The star, named Mira (pronounced my-rah) after the latin word for "wonderful," is shedding material that will be recycled into new stars, planets and possibly even life as it hurls through our galaxy. New ultraviolet images from NASA's Galaxy Evolution Explorer shows a speeding star that is leaving an enormous trail of "seeds" for new solar systems.
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