Astronomy news for the week starting Friday, December 30, 2011.
The Moon celebrates the new year by passing first quarter around midnight on New Year's
Eve, as 2011 gives way to 2012. It then spends the rest of the
week in the waxing gibbous phase, not
reaching full until next week, the night
of Sunday, January 8.
Watch at the beginning of the year for the Moon to spend a trio of
nights with Jupiter. The
early night of Sunday, January 1, the near-quarter will appear to
the right of the giant planet, while the following evening the
growing gibbous will glide five degrees to the north of it. At
about the same time, the Moon is going through apogee, where it
is farthest from Earth. We finish the set on the night of Tuesday
the 3rd with the Moon then well up and to the left of Jupiter. Early in
the week, on New Year's eve the Moon passes north of Uranus, which
still sits within a degree of the Vernal Equinox in Pisces.
The sky is quite littered with planets. Night to night Venus climbs
ever higher, the sky's brightest planet now setting after 7:30 PM,
more than an hour after the end of formal twilight. While admiring
Venus, then look just east of the meridian to find the second brightest,
Jupiter which, south of classical Aries, transits the southern line shortly before Venus-
set. Next, wait until just after 10 PM to watch Mars rise to the
south of eastern Leo, the red
planet making its transit to the south around 4:30 AM. Finally,
around 1:30 AM, just before Jupiter sets, up
comes Saturn, rising
still to the northeast of Spica in
Virgo, the two making a fine
sight as they cross the southeastern sky.
One of the better meteor showers of the year, the
Quadrantids, will peak the morning of
Wednesday the 4th, the shower named after the defunct constellation
Quadrans (the Quadrant), which lies to the east of the Big Dipper's handle. You might see
one a minute or more before dawn. On that evening, that of
Wednesday the 4th, the Earth goes through perihelion, where it is
closest to the Sun, 1.7 percent closer than average. Being the
coldest time of the year, solar distance obviously has nothing to
do with the
seasons, which are caused by the tilt of the Earth's rotation
axis against its orbital axis.
In autumn, we watched the southern constellations of Pisces Austrinus (the Southern Fish, with bright Fomalhaut), Grus (the Crane), Sculptor (the Sculptor's Studio) graze the southern
horizon. Now we have one of the dimmest, Fornax (the Furnace). This almost impossible-to-find
figure lies within the great eastern bend of Eridanus, the River, which has its start at Cursa, Beta Eridani, which is easily
seen just to the northwest of Orion's Rigel.