* Astronomy

Mars is mostly lost in the evening twilight, but with a telescope and a clear view of the southwestern horizon, you might be able to discern the very tiny sliver of the waxing crescent moon - it won't be easy - at dusk on Dec. 6. At 5:35 p.m. Mars, shining red at magnitude 1.3, will suddenly disappear behind the dark moon, as an occultation begins. Mars will not reemerge until the moon is far below the horizon.
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Highlights:
Winter Solstice on December 22nd. This is officially the longest night of 2010, (even though the year's earliest sunset occurs two weeks earlier).
The Geminid meteors on the night of the 13th-14th. Watch out for this reliable shower.

A total lunar eclipse will take place on December 21, 2010, the second of two lunar eclipses in 2010.
The eclipse will be visible throughout most of eastern Asia, Australia, the Pacific Ocean, the Americas, and Europe.

Capricornus, the Sea Goat: Sign of the Zodiac for birth dates between 22 December and 19 January; it is the leading constellation of the "wet" or "water" constellations. Capricornus has a symmetrical shape resembling a bikini bottom, but the stars of Capricornus are very faint with no star brighter than the third magnitude. Capricornus appears low in the southern sky (never at higher altitudes). The Tropic of Capricorn (23.5 degrees South latitude) is named after Capricornus; on 22 December (on average), the Sun is directly overhead (at the zenith) at Noon along the Tropic of Capricorn. In Mythology, the Greeks identified Capricornus with Pan, the god of nature, who was pictured as half-man, half-goat. In fear, Pan escaped the giant Typhon by leaping into the Nile River and changing his tail to that of a fish. This is the origin of the word, "panic."

There are many meteor showers this month...
The Geminid Meteors Shower Peaks on the night of the 13th-14th. 
The Coma Berenicids are a poorly-known minor shower, and badly need more observing. Very swift meteors, (65km/sec). Their Radiant is at RA 11h40m Dec +25°.
Ursids Meteor Shower Peaks on the 17th. A minor shower. The peak is predicted about 2200 UT. The radiant (RA 14h28m Dec +76°) is circumpolar (It never sets in northern locations). The meteors are generally slow (33km/sec) and rates are lower than the Geminids, but certainly above the background sporadic count.
The Ursids are linked with Comet 8P/Tuttle (period around 13.5 years; last at perihelion in 1994). Their peak rates can be quite variable
Also, watch out for sporadic meteors. Their rates for the Northern Hemisphere are now reaching a plateau. Expect around 12 random meteors per hour during the morning hours

Shower	Activity Period	Maximum	Radiant		Velocity	ZHR
		Date	R.A.	Dec.	km/s
Cygnids		Dec 2	13.9h	-12.0°	19.4	82.9
Taurids	Oct 30 -Nov	November	3.1h	-17.5d	25	16
Geminids	Dec	Dec 13	7.6	32.3°	34.7	25.7
Ursids	Dec 22	Dec 17	14.3	77.7°	33.4	10.3