Astronomy news for the week starting Friday, December 10, 1999.

The Moon waxes through its crescent phase this week, reaching first quarter the night of Wednesday the 15th shortly before moonrise in North America. On its way to the quarter it will embrace a host of planets, occulting (or passing over) Neptune on Saturday the 11th and then both Mars and Uranus on Sunday the 12th. Unfortunately the events take place in the daytime. Nevertheless, Mars and the Moon will still put on a nice show in the southwest early on the evening of Sunday the 12th. Since the occultation takes place about 1 PM Central Time, by nightfall the Moon will have moved only a bit to the east, and as a result will make a close couple with the red planet right in the middle of the constellation Capricornus. Go look!

The Moon passes Mars only two hours before passing Uranus, so Mars begins the week just to the west of the much more distant giant planet. Since Mars is closer to the Sun, however, it is moving much faster to the east against the stellar background, and on the night of Monday the 13th will pass only 0.7 degrees to the south of Uranus. The conjunction will provide a fine chance to locate the dimmer planet, which is itself passing an excellent guide, the much brighter fourth magnitude star Theta Capricorni. Look just above Mars to find the star, and then just barely below the star to find Uranus. Though Uranus is at the edge of naked-eye vision, binoculars will be needed.

Our sky is also graced this week by one of the best meteor showers of the year, one that is -- unlike the Leonids of last month -- quite reliable. The Geminids, which appear to radiate from the constellation Gemini, will come to a maximum the night of Monday the 13th. With the Moon out of the way and Gemini climbing the sky, you may see up to two meteors per minute after midnight. The Geminids are the fluffy debris that has been flaked from 3200 Phaeton. Once thought to be an asteroid (and carrying an asteroid's name), Phaeton's connection with the meteor shower clearly indicates it to be a "dead" comet, one whose orbit we pass every December.

While admiring Mars and meteors, be sure also to pay heed to the giants of the Solar System, to Jupiter and Saturn, which are high in the sky just to the south of the flat triangle that makes the classic figure of the constellation Aries. Below them lies Cetus, the Sea Monster of the Perseus myth, its lonely bright star Deneb Kaitos in the monster's tail shining below the Great Square of Pegasus.
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