Skywatch Line for Friday, February 14, through Sunday, February 16, written by Sam Salem
This is Dudley Observatory’s Skywatch Line for Friday, February 14, through Sunday, February 16, written by Sam Salem.
On Friday, Sun rises at 6:53am and sets at 5:26pm; Moon sets at 7:54am and rises at 7:46pm.
On Friday, Venus will reach its greatest brilliancy in the evening sky. Over the next several weeks, it will drop closer to the western horizon, losing a small amount of brightness each night. Venus will slip away from the evening sky in March and emerge in the morning sky in April.
View four bright planets around the evenings this weekend. They will lie along the path the Sun travels in daytime. Venus reaches greatest brilliancy on Friday in dark skies in the western evening sky, with the steady golden light of Saturn lower on the horizon. High overhead is bright Jupiter, and visible most of the night is the red planet, Mars.
On Friday evening, use a telescope to watch Jupiter’s moon Ganymede slowly fade from sight around 7:25pm as it enters eclipse by Jupiter’s shadow. Ganymede will be the one about a Jupiter diameter to Jupiter’s celestial east-northeast. Then watch Ganymede slowly reappear out of Jupiter’s shadow around 9:56pm, farther to Jupiter’s east. Jupiter’s shrunken Great Red Spot should cross the planet’s central meridian about a half hour later, around 10:27pm.
Orion stands at his highest in the south by about 8pm. Under Orion’s feet, and to the right of Sirius now, hides Lepus the Hare. Like Canis Major, this is a constellation with a connect-the-dots that really looks like what it’s supposed to be. It’s a crouching bunny, with his nose pointing lower right, his faint ears extending up toward Rigel, Orion’s brighter foot, and his body bunched to the left. His brightest two stars, 3rd-magnitude Alpha and Beta Leporis, form the back and front of his neck.
Cassiopeia shines high in the northwest, standing almost on end. Near the zenith is Capella. The brightest star about midway between Cassiopeia and Capella, and a little off to the side, is Alpha Persei, magnitude 1.8. It lies on the lower-right edge of the Alpha Persei Cluster, a large, elongated, very loose swarm of fainter stars about the size of your thumb-tip at arm’s length. Alpha Per, a white supergiant, is a member of the group and is its brightest light.
Kemble’s Cascade is a famous dim asterism. It is a straight star chain 2¼° long named in 1980 after its noticer Fr. Lucian Kemble in Canada. It’s located in dim, sprawling, shapeless Camelopardalis the Giraffe. Draw a line from Algol through Alpha Persei. Extend the line farther on by exactly 1½ times that length. You’re now very close to the east end of the chain, a pair of stars magnitudes 6.8 and 6.2 a third of a degree apart.
The Cascade currently hangs down from the southernmost of those two in early evening. You’ll need a dark sky. Averted vision helps for faint sights.
Below its bottom end is a gentle arc of three brighter stars.