Skywatch Line for Monday and Tuesday December 4th and 5th, 2023
This is the Skywatch Line for Monday and Tuesday December 4th and 5th, written by Joe Slomka.
The Sun sets at 4:22 PM; night falls at 6:03. Dawn breaks at 5:29 AM and ends with sunrise at 7:10. Monday, the earliest end of evening takes place at 4:54 PM; earliest sunset is a few days later.
Leo hosts the Moon on both nights. Monday’s northern Moon sets at 12:29 AM and rises at 11:22 PM; by 5 AM Tuesday, it is 52% illuminated, 48° high and sets at 12:48 PM. Tuesday’s Moon is Last Quarter. The Moon rises in southeastern Virgo at 12:24 AM, Wednesday, 43° high at 5 AM, 30 arc-seconds in size and is 39° high.
Mars continues to be too close to the Sun. Saturn and Neptune share Aquarius and both were are up by sunset. Saturn remains to be the first visible planet, but receding from Earth; glows with zero magnitude, 16 arc-seconds, 34° high at 7 PM and sets at 10:27 PM. Southern Neptune follows 23° behind Saturn, smolders with 8th magnitude, 2 arc-seconds, 43° high and sets at 12:34 AM.
Aries is shared by Jupiter and Uranus which also appear well up by sunset. Jupiter rises in the Southeast, gleaming with minus 2nd magnitude, appears a large 47 arc-seconds, 47° at 7 PM, 59° highest at 9:19 PM and sets at 4:09 AM. Monday night, telescopic observers can see the Great Red Spot (a giant storm) cross the planet at 7:59 PM; Tuesday they can witness the moon Io begin to cross the planet at 12:20 AM, followed by its shadow at 1:08, Io’s trip ends at 2:30 and the shadow’s at 3:18. Southern Uranus follows Jupiter by 13°, it flushes with 5th magnitude, 3 arc-seconds, 64° highest at 10:11 and sets at 5:21 AM. Mercury, in southwest Sagittarius, shimmers with zero magnitude, 6 arc-seconds, 4° at 5 PM and sets at 5:31; the planet lies close to the Sun and the horizon, making it difficult to find.
Venus still brings up the rear, in Southeastern Virgo, rising at 3:30 AM, also close to the Sun, blazing with minus 4th magnitude, 16 arc-seconds, 69% lit, 24° high at 6 AM and sets at 8:55.
Every history student knows that December 7th marks the 82nd anniversary of the Japanese attack on Pearl Harbor. Few people are aware of the date’s astronomical significance. The Japanese high command chose that date because the eighteen-day-old Moon rose before midnight and shone at 87 percent, permitting planes to launch during dark and fly to their targets. The Moon almost foiled the surprise raid. The Condor, an American minesweeper spotted a submarine periscope silhouetted against moonlight. The Condor called the Ward, a destroyer, who attacked a second submarine and radioed the incident to headquarters. That report was not heeded. Had that information been acted upon, the American fleet would have had at least an hour and a half to prepare.