Photo of the Week. The second of twelve in the
"Flight across Greenland," going from east to west across the
fantastic glacier. See full resolution.
Astronomy news for the three weeks starting Friday, January 3
2014.
The next Skylights will appear Friday, January 24. Thanks for your
patience.
Welcome to 2014. Over our triple week, the Moon goes through three
quarters of its phase cycle, beginning with a western evening crescent that waxes to first quarter the night of Tuesday, January
7. We then watch the gibbous Moon wax to
full the night of Wednesday the 15th, the
phase hitting around midnight in North America (just a day past
apogee, where it is farthest from Earth). The waning gibbous phase then takes over until third quarter the night of Thursday the 23rd
around the time of Moonrise. The night of Monday the 13th finds
the bright Moon to the west of Jupiter,
while the night of Tuesday the 14th, the Moon will glide five
degrees south of the planet. The following evening Jupiter will
rise ahead of the Moon. The night of Wednesday the 22nd, the Moon
then passes four degrees south of Mars.
Venus and Jupiter
oppose each other. Venus, which has been with us in the evening
over most of 2013, disappears completely as it passes inferior
conjunction (more or less between us and the Sun) on Saturday the
11th. But hold on, as the brilliant second planet from the Sun
quickly pops up in the eastern morning sky, at the end of our
triplex rising near the beginning of dawn. Jupiter, on the other
hand, does the reverse, as it passes opposition to the Sun on
Saturday the 5th. In full
retrograde motion (to the west against the stars), it will rise
at sundown, cross the meridian high to
the south at local midnight (in Gemini to the south of Castor and Pollux), and set at sunrise. Shortly
after Jupiter transits the meridian, look to find Mars rising in
the east against the stars of Virgo. Beginning to the northwest of Spica, it will pass to the north of
the star toward the end of the month. Then around 3 AM (earlier as
the month progresses), Saturn rises in the
southeast in Libra.
Earth passes perihelion with the Sun (1.7 percent closer than
average) on Saturday the 4th. Obviously the solar distance has
little to do with the seasons,
which are caused by the 23.5 degree tilt of the Earth's rotation
axis against its orbital axis. The tilt also factors into the
latest sunrise taking place not at winter solstice passage, but on Tuesday the 7th. In
the early morning of Friday the 3rd, you might catch the peak of
the fine
Quadrantid meteor shower, which seems to come out of the
defunct constellation of Quadrans (the Quadrant) near the
handle of the Big Dipper. It's
one of the best of the year and there is no Moonlight. The Quadrantids are the debris of
the asteroid (or dead comet) 2003 EH1, which orbits the Sun every
5.52 years.
The stars of winter are now in full bloom. Orion hunts high in mid evening, surrounded by his
great grouping that includes Canis
Minor with Procyon to the
east and Canis Major with Sirius to the southeast. If you long
for the stars of summer, look for Vega and Deneb preparing to swing far below Polaris.
