Long-Night Moon
The Moon is full today at 11:49 a.m. CST. As the full Moon closest to the winter solstice, which was yesterday, it is the Long-Night Moon. It will be visible longer than any other full Moon of the year.
Solstice
Today is the winter solstice. It is the shortest day of the year in the northern hemisphere. The Sun rises late, sets early, and scoots low across the sky during the day. The Moon is full, so it is in view longer than any other full Moon of the year.
Moon and Aldebaran
The eye of the bull — the star Aldebaran — stares into the Moon tonight. The brightest star of Taurus is to the lower left of the Moon at nightfall. The Moon will move closer to Aldebaran during the night, to less than the width of a finger held at arm’s length.
Jupiter and Mercury
Jupiter and Mercury, the largest and smallest of the solar system’s major planets, are getting together in the dawn sky. For the next few days, they will be separated by less than the width of your finger held at arm’s length. Jupiter is the brighter of the two.
Zodiac
As twilight fades away, the zodiac arcs high across the southern sky. It is a trail of constellations with one thing in common: The Sun’s path across the sky traverses their borders, so the Sun passes through each of those constellations during the year.
Saturnalia
Today is the beginning of Saturnalia, an ancient Roman festival. The early Christian church may have adopted December 25 as the date for Christmas in part to counteract the appeal of Saturnalia and other festivals.
Messier 37
Messier 37, a 500 million-year-old star cluster, climbs high overhead during the night. It’s not quite visible to the unaided eye, but it’s a fairly easy target for binoculars. It probably is about 5,000 light-years away, and contains about 500 known stars.
Auriga
Auriga is low in the east-northeast as night falls and climbs high across the sky later. It is marked by a pentagon of stars. It’s easy to pick out thanks to the brightest member of that figure, Capella, which is one of the brightest stars in the night sky.
Moon and Mars
Mars is in great view tonight. The Red Planet looks like a bright orange star just above the Moon as night falls. It will stand farther to the right of the Moon tomorrow evening.
Comet Wirtanen
Comet Wirtanen is streaking across Taurus, which is in the east at nightfall. It will pass between the bull’s “eye” — the star Aldebaran — and shoulder — the Pleiades star cluster. Under dark skies, the comet may be bright enough to see with the eye alone.