This is the Dudley Observatory Skywatch Line for Wednesday, July 1st, and Thursday, July 2nd, written by Louis Suarato.
The 86% illuminated, waxing gibbous Moon rises at 5:11 p.m. Wednesday, in the constellation Libra. By astronomical twilight, the Moon will be high over the southern horizon. Jupiter rises in Sagittarius at 9:18 p.m., followed by Saturn 20 minutes later. The two gas giants will be separated by about 6.5 degrees. Thursday night, beginning at 11:38 p.m., Jupiter’s largest moon, Ganymede, will transit the planet. At 1:51 a.m., Friday, Ganymede’s shadow transit will end. At 2:59 a.m., Ganymede’s transit will end. Saturn’s rings are inclined 22 degrees from edge on, providing a good view of the gap between the innermost ring, and the planet. Mars rises at 30 minutes past midnight in the constellation Pisces. Venus rises at 3:22 a.m. Thursday. Friday morning, Venus will be about 3 degrees above Taurus’ brightest star, Aldebaran.
The constellation Sagittarius rises above the southern horizon after midnight. Sagittarius is the fourteenth largest constellation. The majority of stars in this constellation form an asterism known as the Teapot. The “steam” emanating from the Teapot’s spout is the Milky Way. Within the steam, you’ll find, from lowest to highest, M8, the Lagoon Nebula, M20, the Trifid Nebula, open star cluster M23, M24, the Small Sagittarius Star Cloud, and open star cluster M25. Look between Jupiter and the Moon for these deep sky objects.
July 1st is the birth date of astronomer Maria Mitchell. Born in 1818 in Nantucket, Massachusetts, Mitchell was also a librarian, naturalist, and educator. Mitchell may be best known for the discovery of a comet in 1847 that was later to be known as “Miss Mitchell’s Comet”.
There will be an extremely bright -3.8 magnitude International Space Station pass over our region Thursday. The ISS will appear 30 degrees above the west-southwest horizon at 3:34 a.m. Thursday, to the right of the constellation Aquila, and its brightest star Altair. Follow the ISS as it rides along the spine of Cygnus the Swan, sailing past the stars Albireo and Deneb, the head and tail of the swan. Continue to follow the ISS as it passes through Cassiopeia, before heading toward the Double Cluster. The ISS will cross Perseus before disappearing into the northeastern horizon.