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VIRGO
The Virgin
Virgo - Celestial Atlas by Alexander Jamieson - 1822
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In Greek myth the constellation Virgo is associated with Persephone, daughter of Zeus (Jupiter), king of the gods, and Demeter (Ceres), the goddess of agriculture. The story tells of Hades (Pluto) being so captivated by the virginal beauty of Persephone that he abducted her, and carried her off to the underworld to be his wife. Her mother, Demeter was so upset by this, she completely neglected her duties as goddess of agriculture, and famine spread over the entire world. Naturally, Zeus could not let this stand, and decreed that Persephone should leave the underworld and be with her mother for half the year, from March until August. This is the time of year her image appears in the sky, and Demeter does her duty, and crops are sown, cultivated, and harvested. When Virgo leaves the sky in the fall, and descends back into the underworld, Demeter again abandons her duties, and the earth lies fallow until the virgin reappears again in the spring.
Reclining on her side, Virgo stretches across the southern sky, the second largest constellation in the heavens. To identify Virgo, find the bright white star Spica, the alpha star in the constellation Virgo, and the fifteenth brightest star in the sky. Spica comes from the Latin and means ear of wheat, representing, as it does, the coming and going of the growing season. The figure of Virgo is often depicted with a stalk of wheat in her hand.
Once you've located Spica, step back, and let your eyes and your imagination slowly take in the entire form of the reclining maiden, filling the southern sky. Not bad, eh? But you've only just begun, for the virgin holds in her arms a large group of galaxies, known as the Virgo Cluster. Many of the brightest of these galaxies are visible in backyard telescopes.
M104 (NGC 4594), also known as The Sombrero Galaxy, is 28 million light years away, relatively close in astronomical terms. Seen almost edge on, the galaxy is 50,000 light years across (half the size of our Milky Way galaxy), and is unique for the brightness of its central core. Its magnitude of 8.5 puts it just out of naked eye visibility, but easily found in a small telescope.
NGC 5584 is a spiral galaxy 72 million light years from Earth. Although its magnitude of 11.5 puts it well out of the range of naked eye observation, seen through the eyes of the Hubble Space Telescope, the galaxy's true beauty can be fully appreciated. NGC 5584 is also home to 250 special stars known as Cepheid Variables. These types of stars, first discovered in the constellation Cepheus, have predictable properties that make them very useful in measuring distance. The Cephieds in NGC 5584 have been particularly helpful in measuring the expansion rate of the Universe, also known as Hubble's Constant.
M58 is a large face-on spiral galaxy. It is about 62 million light years away, and has a magnitude of 10.5.
M61 is a large face-on spiral galaxy. It is about 50 million light years away, and has a magnitude of 10.18.
So far, thirteen stars in Virgo have been found to support planetary systems, and three of those stars are easy to see with the naked eye. The most exciting of these stars is 61 Virginis, with a magnitude of 4.74, which to date has been found to have three planets in orbit around it. And although almost all exoplanets discovered are gas giants larger than Jupiter, these planets are much smaller, the smallest only one hundredth the size of Jupiter, and therefore much more likely to support some kind of life! And this planetary system is quite close (in astronomical terms), only 27 light years away from Earth.
The star 70 Virginis, with a magnitude of 5.0, is 59 light years away, and has one planet six times larger than Jupiter. The star HD 110014, with a magnitude of 4.66, is much further away at 292 light years. It too, only has one planet discovered so far, and it is more than eleven times larger than Jupiter.
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