Skywatch Line for Friday, March 29, through Sunday, March 31, 2024 written by Sam Salem

This is Dudley Observatory’s Skywatch Line for Friday, March 29, through Sunday, March 31, written by Sam Salem.

On Friday, Sun rises at 6:42am and sets at 7:19pm; Moon sets at 8:26am.

On Saturday and Sunday mornings, the waning gibbous Moon will lie close to the bright star Antares in the constellation of Scorpius the Scorpion.

Mercury is fading fast. Try to find it about two fists lower right of Jupiter in twilight. Look for it almost due west about two fists at arm’s length below or lower right of bright Jupiter about 45 minutes after sunset. Mercury fade rapidly this week from a prominent magnitude –0.4 to a bashful +1.0, a loss of nearly three quarters of its light, even as it remains at about the same height.

Jupiter, at magnitude –2.1 in the constellation of Aries, is the bright “star” shining due west in twilight. It sinks lower after dark and sets around 11 pm. It’s becoming the only easy planet in the sky.

Uranus, at magnitude 5.8 in the constellation of Aries, hides 4° or 5° above Jupiter in the early evening sky. Right after darkness is complete, use the finder charts for to locate Uranus.

Perseus, with Algol on his stick-figure leg, is getting lower in the northwest as the season advances. Friday evening is one of last good chances until next fall to catch Algol in eclipse. It should be at its minimum brightness, magnitude 3.4 instead of its usual 2.1, for a couple hours centered on 6:52 pm. Algol will take several additional hours to re-brighten.

Comet Pons-Brooks is low in the west right after dark. At a predicted 5th magnitude, it should be located easily in binoculars or a small telescope. Look right after twilight ends. On Saturday evening, it’s passing only about ½° from 2nd-magnitude star Alpha Arietis (Hamal). Look just to the star’s right or lower right. The Comet’s tail points up.

Right after dark, Sirius shines brilliantly in the south-southwest. Lower left of it, by about one fist, is the triangle of Adhara, Wezen, and Aludra, from right to left. They form Canis Major’s hind foot, rear end, and tail, respectively. Alternatively, they’re the lower end and handle of the Meat Cleaver. Just left or upper left of the triangle, forming a 3rd- and 4th-magnitude arc that’s a bit larger than the triangle, are the three uppermost stars of the constellation Puppis. It’s not a puppy, despite following right behind the Big Dog. It’s the Poop Deck (stern) of the giant ancient constellation Argo Navis, the ship of Jason and the Argonauts. These three are the only stars of Argo that are readily visible naked-eye from mid-northern latitudes. Just 1.5° upper right of the middle of the three, binoculars on a dark night will show the little 6th-magnitude open cluster M93. It’s elongated northeast-southwest. M93, also known as NGC2447 or the Critter Cluster, is an open cluster in the modestly southern constellation Puppis.