This is the Skywatch Line for Monday and Tuesday, December 24th and 25th.
The Sun sets at 4:26 PM; night falls at 6:08. Dawn begins at 5:42 AM and ends with the Sun rising at 7:24.
Mars is the only easily identified planet in our evening sky. The Red Planet shines with zero magnitude in Pisces, appears almost 87% illuminated and about 8 arc-seconds in size. It lies roughly 44º high in the southern sky. It is best observed at 5:25 PM and sets at 11:19 PM.
Neptune, in Aquarius, is no longer close to Mars, but lies nearly 11º west of Mars. Neptune shines with 8th magnitude, is a tiny 2.3 arc-seconds in size and lies 40º high in the South. It is highest at 4:44 PM and sets at 10:19 PM. Uranus, in Pisces, is the other difficult planet. It is brighter at 5th magnitude and is a larger 3.6 arc-seconds in our telescopes. Uranus shares Pisces with Mars, but is at the opposite end of the constellation. Uranus, near the star Omicron Piscium, is best observed at 7:28 PM and sets at 2:10 AM. Both planets require finder charts from astronomical media.
The waning 17-day-old Moon rises in Cancer at 6:51 PM, Monday. It blazes at minus 11th magnitude and appears 92% lit. Tuesday at Midnight, it is less than a degree from M44 (The Beehive). The Moon’s glare will hinder the observer from seeing the star cluster that night, but the observer should remember where it was and check the next night. The Moon sets at 2:27 AM, Tuesday, but rises at 8:05 PM in Leo and sets at 3:26 AM, Wednesday.
The variable star Algol, in Perseus, has minimum brightness at 9:17 PM Tuesday. Sky watchers should begin monitoring the star 2 hours before minimum through to 2 hours after the minimum.
Comet P/46 Wirtanen is now retreating from Earth. It travels about 4º per day. It is quite high in the sky and reported to be naked-eye visible. It was closest to the bright star Capella in Auriga and is moving northeastward. Wirtanen should appear as a greenish haze, without a tail. Finder charts assist the comet chaser.
Venus, in Libra, rises at 3:32 AM, blazes with minus 4th magnitude and appears about 44% lit. By Dawn, it is approximately 20º high in the southeast sky and at Civil Dawn it is 28º high. Jupiter, in Ophiuchus, returns to our skies and rises at 5:36 AM and, by Civil Dawn, 10º high. Jupiter shines with minus 1st magnitude and is a large 31 arc-seconds in our instruments. Jupiter acts as a guide to Mercury, also in Ophiuchus, which rises at 5:55 AM and is 4º below Jupiter. Mercury appears 86% lit and glows with minus zero magnitude.
This time of the year was dedicated to Saturn, the Roman God of Harvests. A series of feasts were held during the week of the Winter Solstice – the Saturnalia. Saturn was depicted as a jolly old man. People decorated evergreen trees. Candles were lit everywhere. Houses were decorated with wreaths and Holly. Decorated cookies were baked. People wore red peaked hats, similar to the “Santa hats” of today. Banquets were held both in honor of the harvest and wishing for a prosperous new year. Gifts were exchanged: dolls for the children, candles and fruits for adults. Donations and benefits were held for the poor. Saturnalia was an official government holiday. The holiday was so popular that Christians moved the feast of Christ’s birth to compete and adopted many of the symbols and traditions of this pagan feast.
The Dudley Observatory and Albany Amateur Astronomers wish their followers Happy Holidays.