DECEMBER 2009–OBSERVING HIGHLIGHTS
EARTH SATELLITES:
Moon –
New moon -
16TH
1st Quarter –
24th
Full moon –
2nd
Last quarter
– 8th PLANETS: MERCURY: Mercury pops out of the sun’s glow during
December’s second week. Look to the South Western horizon December 9th. The planet stands 5 degrees high 30 minutes
after sunset and shines at a magnitude of –0.6.
The innermost planet climbs higher in the evening sky each night until
December 18th when it reaches greatest elongation from the sun. That
night a slender crescent moon stands 6 degrees to Mercury’s upper left. JUPITER:
Jupiter as always outshines everything but the Moon in December. Look
for it in the Southwest twilight. This
year provides an extra treat for Jupiter observers. The Galilean moons undergo a series of
so-called mafal events. In some, one Moon passes in
front of another and occults it from view. In others, a moon shadow falls on
another and partially or totally eclipses it.
This happened at the last star party in Aiken, where one moon occulted
another one. On December 2nd
at 9:08 PM, IO passes in front of Europa. And on December 14th at 7:26 PM, Europa occults IO. NEPTUNE:
On December 19th URANUS:
Look in the Southwestern sky to find Uranus. It glows at 5.8 magnitude and shows up easily
in binoculars. To fin Uranus, look South
of Pisces MARS:
Mars is approaching its best appearance in 2 years. It rises by 10:00 PM on December 1st
and 2 hours earlier by month’s end. The
best view through a telescope comes from midnight on. Mars North polar cap will be on prime display
because the planet’s Northern hemisphere now tilts in Earth’s direction. Look for the red planet in LEO. SATURN:
Rises 4 hours after Mars and appears high in the South shortly before
dawn. It stands among the stars of Virgo
the Maiden. Saturn’s rings provide a stunning
view through a telescope. They tilt 5
degrees to our line of sight by year’s end.
Saturn’s brightest moon Titan, shows up through
any telescope. Also look for Saturn’s
outer moon, Iapetus.
It lies 8 degrees west of Saturn and glows at 10th magnitude.
VENUS:
Venus remains lost in the Sun’s glare all month. The Geminid meteor shower peaks
before dawn on December 14th with the moon out of the way, observers
with dark skies may see 100 meteors per hour.
Also another meteor shower, the Ursids
peak before dawn on December 22nd.
Espect to see between 10-50
per hour.
Circlet asterism. It lies due West of the 5th
magnitude Star 27 Piscium.
