Fast Swimmer

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The fastest swimmer in the sea is the sailfish. In short bursts, it can reach speeds of almost 70 miles an hour. But one of the fastest swimmers in the celestial sea moves a bit quicker -- more than 300,000 miles an hour.

This speedy object is the star Gamma Piscium, one of the brightest stars of Pisces, the fishes. Pisces is one of several water-related constellations that form a region known as the celestial sea.

Gamma Piscium is nearing the end of its life, so it's puffing up like a balloon. It's about a dozen times wider than the Sun, and several dozen times brighter.

This profile doesn't have anything to do with its speed, though. Instead, the star is moving so briskly because it's an outsider -- it was born somewhere else and is just passing through our region of the galaxy.

It could have been born in another region of the Milky Way, or it might hail from a completely different galaxy. Over its long lifetime, the Milky Way has gobbled up quite a few smaller galaxies. Eventually, the stars spread out and go their own ways, making it harder to figure out where they came from.

Regardless of its origin, Gamma Piscium is blazing past us at more than 80 miles a second, so it'll soon move out of sight.

For now, the star is barely visible near the southern edge of Pisces. It's in the southeast at nightfall, well to the upper left of Fomalhaut, the only really bright star in that region of the sky.

Script by Damond Benningfield, Copyright 2008

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