This is the Dudley Observatory Skywatch Line for Wednesday, March 25th, and Thursday, March 26th, written by Louis Suarato.
The 2% illuminated, waxing crescent Moon sets at 8:32 p.m. Wednesday. High above the Moon, you’ll find brilliant Venus, 50% illuminated, and shining at -4.5 magnitude. Thursday night, the crescent Moon will be 20 degrees below Venus. Look 7 degrees above Venus for the Pleiades star cluster. On April 3rd, Venus and the Pleiades will only be separated by ¼ of a degree. If you star hop from Venus to the next brightest star to its upper left, Aldebaran, and the next brightest star to Aldebaran’s upper left, you’ll land on Betelgeuse in the constellation Orion. You’ll notice Betelgeuse is brightening again. Jupiter leads the overnight planet parade, rising at 3:41 a.m. Thursday. Mars follows 16 minutes later, and Saturn rises 6 minutes after Mars. Jupiter and Saturn will be separated by 6 degrees. This is the closest these three planets have been in two decades. Wednesday is the 365th anniversary of Christiaan Huygen’s discovery of Saturn’s largest moon, Titan.
Mercury rises at 5:55 a.m. Thursday. Mercury reaches perihelion, the farthest distance from the Sun during its annual orbit, on Thursday. Mercury orbits the Sun once every 88 days at an average distance of 0.387 astronomical units, or 35.9 million miles. Mercury has the highest eccentricity, its variation from a perfectly circular orbit, than any other planet in the solar system, at 0.205. Mercury’s distance from the Sun varies from 28.5 million miles at perihelion, to 57.9 million miles at aphelion.
Comet P/2019 Y4 (Atlas) was discovered on December 28, 2019, in Hawaii, by the ATLAS (Asteroid Terrestrial-Impact Last Alert System), Survey. Comet Atlas will make its closest approach to Earth on May 23, 2020. It will reach perihelion on May 31, and may be seen with the naked eye afterward. Comet Atlas can be seen now by using the Big Dipper’s star, Dubhe to locate it. Look about 20 degrees to the north of Dubhe for the comet. You can also look about 25 degrees above Polaris. Wednesday night, the coordinates will be AZ: +6°10’ ALT: 64°00’.