* Astronomy

Blobrana · L

RE: December 2012

Blobrana · L

Last Quarter Moon (diameter: 31.097') at 15:31.4 UT, 6th December, 2012.

Blobrana · L

Mercury at its Greatest Western Elongation (20.6° West) at 22:43 UT, 4th December, 2012

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Eyes on the Sky: Dec 3 thru Dec 9

Credit eyesontheskyDOTcom

Aries the Ram is a small constellation, but has a special significance in the night sky because of the way the celestial coordinate system is set up.

Blobrana · L

Jupiter is at Opposition at 01:45 UT, 3rd December, 2012

Spoiler

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Mercury rise in the constellation Libra at 06:13.3 UT, 2nd December (For Scotland)

Blobrana · L

Asteroid at Opposition

Asteroid (24) Themis is at Opposition on the 1st December, 2012.
Magnitude: 11.0
Distance to Earth: 1.988 au
Distance to Sun: 2.974 au

Asteroid (352) Gisela is at Opposition on the 2nd December, 2012.
Magnitude: 11.3
Distance to Earth: 0.936 au
Distance to Sun: 1.922 au

Asteroid (4) Vesta is at Opposition on the 9th December, 2012.
Magnitude: 6.4
Distance to Earth: 1.588 au
Distance to Sun: 2.571 au

Asteroid (135) Hertha is at Opposition on the 9th December, 2012.
Magnitude: 11.4
Distance to Earth: 1.555 au
Distance to Sun: 2.539 au

Asteroid (521) Brixia is at Opposition on the 15th December, 2012.
Magnitude: 10.2
Distance to Earth: 1.075 au
Distance to Sun: 2.059 au

Asteroid (43) Ariadne is at Opposition on the 16th December, 2012.
Magnitude: 11.0
Distance to Earth: 1.570 au
Distance to Sun: 2.554 au

Asteroid (1) Ceres is at Opposition on the 18th December, 2012.
Magnitude: 6.7
Distance to Earth: 1.685 au
Distance to Sun: 2.668 au

Asteroid (21) Lutetia is at Opposition on the 23rd December, 2012.
Magnitude: 10.5
Distance to Earth: 1.600 au
Distance to Sun: 2.584 au

Asteroid (48) Doris is at Opposition on the 23rd December, 2012.
Magnitude: 10.9
Distance to Earth: 1.913 au
Distance to Sun: 2.887 au

Blobrana · L

Highlights:

Winter Solstice on December 21st. This is officially the longest night of 2012, (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.

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."

Meteor Showers

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 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

Blobrana · L

Mercury: at magnitude -0.3, starts the month in the constellation of Libra. Mercury is at Dichotomy (Half phase) on the 1st December. The planet is best seen from 6.3h - 8.0h. Mercury is 1.1° from the Moon on the 12th.
(On December 1st, RA=15h11m03s Dec=-15°08.4' (J2000) Distance=0.919AU Phase k=48% Diameter=7.3")

Venus: is at magnitude -4.0. The planet is in constellation Libra at the start of the month. It is best seen from 5.5h -14.6h. The Moon is 1.5° from Venus on the 11th.
(On December 1st, RA=14h37m10s Dec=-13°36.0' (J2000) Distance=1.420AU Phase k=88% Diameter=11.7")

Earth: winter solstice will occur at 11:12 UTC on December 21, 2012.

The Moon: The Full Moon is on the 28th. Lunar perigee is on the 12th. Last Quarter Moon is in the 6th. Lunar apogee in the 25th. The New Moon is on the 13th. The First Quarter Moon is on the 20th.

Mars: at magnitude 1.2 starts the month in the constellation Sagittarius. The planet is best seen from 16.3h -17.3h. The Moon is 5.4° from Mars on the 15th.
(On December 1st, RA=18h47m54s Dec=-24°08.3' (J2000) Distance=2.148AU Phase k=96% Diameter=4.4")

Jupiter: is in the constellation Taurus. At magnitude -2.8, the planet is best seen from 15.5h - 8.4h. Jupiter makes its closest approach to the Earth (4.069 AU, brightness, diameter: 48.39") on the 1st December. Jupiter is 0.5° from the Moon on the 26th.

Transit times of the Great Red Spot are posted in a seprate thread.
(On December 1st, RA= 4h39m29s Dec=+21°20.6' (J2000) Distance=4.069AU Diameter=48.4")

Saturn: at magnitude 0.6 sits in the constellation Virgo. The planet is best seen from 5.0h - 8.0h. Saturn is 3.8° from the Moon on the 10th. The planet's rings are tilted 19° towards the Earth this month.
(On December 1st, RA=14h19m35s Dec=-11°32.1' (J2000) Distance=10.598AU Diameter=15.6")

Uranus: is in the constellation Pisces. Uranus at magnitude 5.8, has a bluish-green hue and appears 3.6 arcseconds wide. Uranus is stationary on the 13th. Uranus is 4.7° from the Moon on the 20th.
(On December 1st, RA= 0h17m37s Dec= +1°07.0' (J2000) Distance=19.627AU Diameter=3.6")

Neptune: is at magnitude 7.9 in the constellation Aquarius. The planet is best seen from 17.6h -18.5h. Neptune is 5.8° from the Moon on the 18th.
(On December 1st, RA=22h10m22s Dec=-11°56.5' (J2000) Distance=30.138AU Diameter=2.2")

Pluto: is in the constellation Sagittarius (mag 14.1). Normally, a finder chart is necessary to help in identifying the 0.13" diameter dwarf planet. The dwarf planet is best seen from 17.5h - 6.4h. Pluto is 0.1° from the Moon on the 14th.
(On December 1st, RA=18h34m24s Dec=-19°48.5' (J2000) Distance=33.205AU Diameter=0.1")

The Sun enters the zodiac sign Capricorn at 11:12 UT, 21st December.

Blobrana · L

                                 December
 d  h                                  d  h
 3  1  Jupiter at opposition          14 11  Pluto 0.1S of Moon      Occn
 5  6  Mercury greatest elong W(21)   15  8  Mars 5.4S of Moon
 5 11  Regulus 5.7N of Moon           18  2  Neptune 5.8S of Moon
 6 15  LAST QUARTER                   18  5  Mercury 5.4N of Antares 
 9 11  Spica 0.6N of Moon      Occn   20  5  FIRST QUARTER
10 10  Saturn 3.8N of Moon            20 16  Uranus 4.7S of Moon
11 13  Venus 1.5N of Moon             21 11  Solstice
12  0  Mercury 1.1N of Moon    Occn   24  3  Venus 5.6N of Antares 
12 14  Antares 5.9S of Moon           25 21  Moon at apogee
12 22  Jupiter 4.7N of Aldebaran      26  0  Jupiter 0.5N of Moon    Occn
12 23  Moon at perigee                26  3  Aldebaran 4.1S of Moon
13  4  Moon furthest South (-20.9)    26 22  Moon furthest North (20.9)
13  8  NEW MOON                       28 10  FULL MOON
13 20  Uranus stationary              30 13  Pluto at conjunction