Skywatch Line for Monday and Tuesday, August 26th and 27th, written by Joe Slomka
This is the Skywatch Line for Monday and Tuesday, August 26th and 27th, written by Joe Slomka.
The Sun sets at 7:39 PM; night falls at 9:21. Dawn begins at 4:33 AM and ends with the Sun rising at 6:15.
Monday’s Moon, in Taurus, is officially Last Quarter at 5:26 AM, sets at 2:47 PM and rises at 11:26 PM; Tuesday, the Moon sets at 3:56 PM and rises at 12:17 AM on Wednesday. Monday’s Moon lies 3° from the Pleiades.
There are two planets in the evening sky. Venus, in Leo, clings to the western horizon, only 20° from the Sun, blazes with minus 4th magnitude, 10 arc-seconds, 6° high at 8 PM and sets at 8:40. Dwarf planet 1Ceres is in low Sagittarius, rising at 5:16 PM, 16° highest at 9:06 PM and sets at 1 AM; Monday, Ceres lies stationary, before reversing.
Saturn remains first, in southwestern Aquarius, rising at 8:42 PM, zero magnitude, moderate 19 arc-seconds, highest at 2:19 AM and 23° high at 5 AM. Neptune, 12° from Saturn, dwells in Pisces, 7th magnitude, 2 arc-seconds, rises at 9:04 PM, 34° in the West at 5 AM.
Eastern Taurus again hosts Uranus, Jupiter and Mars. Uranus rises at 11:23 PM, 5th magnitude, 3 arc-seconds, 62° at 5 AM. Jupiter, 21° from Uranus, rises at 12:39 AM, 2nd magnitude and 51° high; Tuesday, Jupiter appears less than 5° from Moon. Telescopic observers can witness the Jovian moon Ganymede’s occultation (eclipse) begin at 1:53 AM and end at 3:54 AM. The Great Red Spot (a giant storm) becomes visible at 4:04 AM on Wednesday. Mars, 6° from Jupiter, rises at 12:46 AM, zero magnitude, 6 arc-seconds and becoming brighter, 46° high and illuminated 88%. Finally, eastern Mercury posing a challenge, resides in Leo, only 13° from the Sun, 2nd magnitude, 9 arc-seconds, rises during twilight at 5:14 AM, 7° illuminated, and best seen 1 hour before Sunrise; it also is static.
Pre-dawn planets see a lot of action. Tuesday, Jupiter and Mars lie 6.3° and 6.8° on Wednesday, 4 hours before Sunrise. Note that Jupiter, Mars, Uranus, Moon, Saturn and Neptune form a straight line, Tuesday at about 2 AM.
French astronomer Pierre Mechain discovered M75 in 1780, in the constellation Sagittarius. He told his friend, comet hunter Charles Messier, who listed this object as number seventy-five in his list of comet lookalikes. In 1784, British astronomer William Herschel estimated the distance to this “nebula without stars” as six thousand light-years. We now know that M75 is a globular star cluster. Globular clusters are usually found around galaxy halos and central bulges. Globulars may contain up to a million stars and are quite large, in a sphere about 100 light-years across. These stars are quite old. Modern estimates place M75 at about fifty-nine thousand light-years away. Astronomers also describe it as one of the most compact globulars in the sky. Only the largest telescopes can resolve the cluster into individual stars.
Clear Skies Joe Slomka