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SPICA
Spica, the luminary of Virgo, becomes prominent in the southeast in northern spring evenings, and can easily be found by following the curve of the Big Dipper's handle through Arcturus and then on down. Though a large constellation, Virgo, the Virgin, does not have much of any prominent stellar pattern, relying on Spica to tell us where it is. The star lies about 10 degrees south of the celestial equator, and practically on the ecliptic, the path of the Sun, and is regularly occulted, or covered over, by the Moon. The Sun passes Spica in the fall, rendering the star a harvest symbol that is reflected in its name, from Latin meaning "ear of wheat," the name actually going back to much more ancient times. Though at a distance of 260 light years, Spica is still first magnitude, showing its absolute brilliance, the star 2100 times more luminous than the Sun. The brightness is a bit deceptive, however, as Spica actually consists of two stars very close together that orbit each other with a period of only four days. At least one of them is a dying giant. Both are blue in color and quite hot, with temperatures in excess of 20,000 degrees Kelvin. There is evidence that Spica is in fact multiple, containing two other fainter components. Spica is a strong source of X-rays, at least some of which seem to be produced when the winds that flow from the brilliant companions violently collide together.