Astronomy news for the week starting Friday, June 9, 2000.

We have another week with no quarterings of the lunar orbit. The Moon went through its first quarter on Thursday, June 8, and will pass full next Friday, June 16, so the during Skylight's entire week, the Moon will be in its waxing gibbous phase, getting ever brighter and blotting out more and more stars.

The week, however, belongs not to the Moon but to the two inferior planets, Mercury and Venus, so called from ancient times because they are "below" the Earth, that is, between the Earth and the Sun. Those outside our orbit, "above" the Earth from Mars on out are the superior planets. Little Mercury passes its greatest eastern elongation, when it is 24 degrees to the east of the Sun, on Friday the 9th, and for a very short period will be at its best for viewing. Look for a bright "star" low in the west-northwest in evening twilight below Castor and Pollux in Gemini. Mercury is so close to the Sun that it is never seen in full darkness. If Mercury is at his best for viewing, Venus is at her worst. This nearest of all planets passes superior conjunction with the Sun on Sunday the 11th. Each of the inferior planets goes through two kinds of conjunction, once between us and the Sun (inferior conjunction) and again on the other side of the Sun (superior conjunction). Venus now moves from a morning to an evening object, though it will be next month before it becomes readily visible in evening twilight. In the morning dawn sky, look for Jupiter and Saturn, the giant of the Solar System now to the east of the Ringed Planet.

By 10 PM, two first magnitude stars, Arcturus and Spica, ride the meridian high in the sky, Arcturus the more northerly of the two. The pair, separated by about 30 degrees, provide a fine color contrast as a result of very different temperatures, Arcturus (about 4000 degrees Celsius at its surface) an orange giant star and Spica (20,000 Celsius and actually double) a pale blue-white. Arcturus and its parent constellation Bootes (the Herdsman) are surrounded by celestial monuments to women. To the west of Arcturus find the sprawling cluster Coma Berenices (Berenices Hair, testimony to an ancient queen) and to the east Corona Borealis (the Northern Crown, which honors Ariadne). To the south is Virgo (the Virgin), which contains Spica. Other feminine figures include northern autumn's Cassiopeia (the Queen) and her daughter Andromeda. Often not recognized is the feminine side of one of the sky's most prominent constellations, Orion, who to the Arabs was Al Jauza (a womanly "Central" figure of some sort), the name still ringing in the origins of the names of Orion's two bright stars, Betelgeuse and Rigel.
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