Skywatch Line for Monday and Tuesday June 12th, and 13th, 2023
This is the Dudley Observatory’s Skywatch Line for Monday and Tuesday June 12th, and 13th, written by Joe Slomka.
The Sun sets at 8:34 PM; night falls at 10:50. Dawn begins at 3:01 AM and ends with the Sun rising at 5:17.
Monday and Tuesday’s Moon resides in Pisces. Monday’s Moon rose at 2:06 AM and sets at 2:55 PM. Tuesday, the Moon rises at 2:28 AM, 15° high in the East, 31 arc-seconds in size, 24% illuminated and sets at 4:06 PM. The Moon shifts to eastern Aries for Wednesday, rises at 2:50 AM, 11° high, same size, but 15% lit and sets during daytime. Wednesday’s Moon will show “earthshine”- light bounced off of Earth; look before Dawn gets too bright.
The constellation Cancer houses Venus, Mars, and Dwarf Planet 1Ceres. Venus is the brightest, blazing with minus 4th magnitude, 26 arc-seconds, 26° high at 9 PM, 44% crescent and sets at 11:31 PM. Red planet Mars lies 6° below Venus, glows with 1st magnitude, almost 50 arc-seconds, 94% lit up, 30° high and sets at 11:46 PM; Mars creeps eastward. With the Moon out of the way, this is an ideal time to observe Venus, Mars, and the Beehive star cluster; binoculars show Venus only 0.6° away. Ceres is available to the observer, about 6° to the left of Leo’s tail star – Denebola; Ceres glows with 8th magnitude, 96% lit, 53° high at 9 PM and sets at 2:25 AM.
Saturn is the first to rise, in southeastern Aquarius, at 12:50 AM, glowing with zero magnitude, 17 arc-seconds and 29° at 4 AM. Neptune follows, in Pisces, 20° to Saturn’s left, glimmering with 5th magnitude, 3 arc-seconds, rises at 1:34 AM and is 26° high.
Giant Jupiter shares eastern Aries with Uranus and the Moon. It glares with minus 2nd magnitude, a large 35 arc-seconds, it rises at 3:02 AM and is 11° high by 4 AM. On Tuesday and Wednesday, 11° separates the Moon and Jupiter. Jupiter is rising early enough to permit observing some of its moons. Callisto, with 6th magnitude lies 8° from Jupiter, while Europa is closer – only 32 arc-seconds. Neptune is 15° East of Jupiter, glistens with 5th magnitude, a tiny 3 arc-seconds, rises at 3:38 AM and is 4° high. Finally, Mercury, in Taurus, crawls sunward, which makes observation difficult; it shines with minus zero magnitude, 6 arc-seconds, rises at 4:20 AM and 4° high at 4:45 AM.
If you follow the “arc” of the Big Dipper’s handle, you come to the bright star Arcturus. Arcturus is the sixth brightest star and one of the nearest, only 37 light-years away. Arcturus is a giant, about 25 times larger than our Sun. Arcturus is rapidly approaching our solar system. Thousands of years from now, Arcturus will brighten, loom larger, speed past us and then disappear into space. A new theory thinks that Arcturus, and other stars, are actually part of a small galaxy that our own Milky Way gobbled up in the recent past.