Skywatch Line for Monday and Tuesday February 24th, and 25th, written by Joe Slomka

This is Dudley Observatory’s Skywatch Line for Monday and Tuesday February 24th, and 25th, written by Joe Slomka.

The Sun sets at 5:39 PM; night falls at 7:13. Dawn begins at 5:03 AM and ends with Sunrise at 6:37.

The Moon, in Sagittarius, rises at 4:55 AM, shines during daytime, 25 days old, 12% illuminated and sets at 1:24 PM. Tuesday’s Moon shifts to Capricornus, rises at 5:35 AM, also in daytime and sets at 2:49 PM; it is the last easily seen Moon before “New”.

Saturn, Mercury and Neptune are too close to the Sun and not visible. Western Venus is first visible planet, in Pisces, rises at 7:29 AM, highest at 2:03 PM, flashes with minus 4th magnitude, appears 46 arc-seconds in size, 18% lit at 7 PM and sets at 8:42 PM.

Uranus, in South Western Aries, rises at 9:48 AM, glimmers with 6th magnitude, appears 3 arc-seconds, highest at 4:59 PM, 55° highest at 7 PM and sets at 12:18 AM.

Jupiter, still in Southeastern Taurus, rises at 10:50 AM, flashes with minus 2nd magnitude, appears 40 arc-seconds, highest at 6:16 PM, and sets at 1:49 AM. Monday, the moon IO’s shadow begins to travel at 8:07 PM and ends at 10:22 PM; the Great Red Spot (a giant storm) is visible at 9:39 PM. Wednesday displays the Great Red Spot at 3:26 AM.

Mars, in Southeast Gemini, rises at 1PM, and sets at 4:43 AM, appears 94% lit and 62° high at 7 PM, 73° highest at 10 PM. Mars is found between Castor and Pollux. Monday, Mars is stationary and will resume prograde (eastward) motion.

Comet 29P remains in our skies. In Leo, it rises at 4:46 PM, appears near Regulus, highest at 11:25 PM, magnitude 15 and sets at 6:08 AM.

Friday is February 28. When most months have 30 or 31 days, why does February have 28? The old Roman calendar was a lunar calendar of ten months containing 304 days. There was no system for inserting “leap months.” The result was chaos. While Julius Caesar was in Egypt, he met Sosigenes, a prominent mathematician, who suggested reforms to the Roman calendar.

Caesar adopted those reforms that resulted in the current system of twelve months containing 365 days and leap years. Caesar made January the first month (after the god of beginnings). What is less well known is that he shifted a day from February to the newly named month of July (after himself). Augustus, his successor, also borrowed a day from February, so that August (his month) would be equally as long as July.

Clear Skies