Skywatch Line for Monday and Tuesday, September 16th and 17th, written by Joe Slomka
This is the Skywatch Line for Monday and Tuesday, September 16th and 17th, written by Joe Slomka.
The Sun sets at 7:02 PM; night falls at 8:38. Dawn begins at 5:02 AM and ends with the Sun rising at 6:38.
Aquarius hosts both Moons. Monday’s set at 4:25 AM, rises at 6:25 PM, by 7:30 PM it 8° high in the East, 33 arc-minutes in size and 98% illuminated. Tuesday’s is a Full Moon, sets at 5:46 AM and rises at 6:58 PM; “Full Moon” means that the Moon blazes all night. Tuesday presents a partial eclipse visible to people in eastern North America. It begins at 10:12 PM, greatest eclipse occurs at 10:44 and ends at 11:17 PM.
Western Venus, in Virgo, is first, 28° from the Sun, blazes with minus 4th magnitude, 12 arc-seconds, rises at 9:02 AM, 6° high, 88% lit and sets at 8:02 PM. Southern Dwarf Planet 1Ceres is observable due to its distance from the Moon. It rises at 3:59 PM, 16° highest at 7:50 PM, 97% illuminated, and sets at 11:41 PM. Saturn and Neptune will be difficult because the of the Moon’s proximity and minus 12th magnitude.
Uranus and Jupiter share southern Taurus. Uranus rises at 9:33 PM, 5th magnitude, 3 arc-seconds and by 6 AM it is 62° high. Giant planet Jupiter lies 13° East of Uranus, rises at 10:57 PM, minus 2nd magnitude, 40 arc-seconds and 69° highest. Red Planet Mars now occupies Gemini, rises at 12:06 AM, zero magnitude, 7 arc-seconds and 62° highest. Mercury, in Leo, brings up the rear, only 12° from the Sun, shines with minus 1st magnitude, 5 arc-seconds, 90% illuminated, but is 4° high at 5:36 AM. These set during day.
There some objects that are perfect binocular targets. Directly overhead, the constellation Cygnus seems to fly south for the winter. Below the neck of the Swan is a small constellation – Sagitta. The Latin name means “arrow”, and that is exactly what it looks like. Sagitta is has a single deep sky object, M71. M71 is a star cluster of uncertain type; displays characteristics of both globular and galactic clusters. M71 lies about 18,000 light years distant, and 30 light-years wide. A binocular observer should see a fuzzy glow about halfway along and a bit below the arrow’s shaft.
Just above the “Arrow’s” tail feathers is a curious object. The “Coathanger” is an asterism – an image of stars, but not a constellation. This is a wonderful binocular target, since a telescope’s magnification destroys the illusion. The Coathanger also goes by the names: Collinder 399 and Brocchi’s Cluster. The Coathanger is not a true cluster. Hipparchus satellite measurements show that it is just a random placement of stars that happen to resemble an everyday article.
Clear Skies Joe Slomka