March 2021

Cetus, Pisces, and Pegasus are setting as night sets in. Gemini, Taurus, and Orion are high at sunset. Leo is an all night constellation. Mars is in Taurus when March begins. It passes close to the Pleiades in the first week. Around the 15^th through 19^th, the red planet passes through a set of stars sharing the name Alkalbain. The moon is near on the 19^th. By the end of March as Taurus is lower in the west, Mars is above the Hyades V with orange Aldebaran and below Elnath in Auriga.

Libra rises around local midnight.

A cluster of planets rises shortly before the sun. Saturn is highest, Mercury is next, and Jupiter is below it when the month starts. Mercury is moving toward Jupiter and passes it on the 4^th and 5^th. The messenger planet is at greatest elongation on the 6^th, 27.3° west of the sun. A waning crescent moon is in the neighborhood on the 9^th and 10^th. For northern hemisphere viewers, Saturn and Jupiter stay barely above the solar glare as Mercury disappears into it in the second half of March. In the southern hemisphere, sky watchers will still see the messenger planet above a clear horizon in the morning at the end of the month. From 25° south, Mercury rises 1 hour, 12 minutes before the sun nearly above it on the 31^st.

Venus is close to the sun all month. There are no places on Earth that get a good view of it this month. Venus is technically a morning object until the 26^th when it’s at superior conjunction and changes to evening status.

The equinox is on the 20^th.

Mercury is at aphelion on the 14^th. It’s 0.467 astronomical units from the sun.

The asteroid Vesta is at opposition on March 4^th. It’s 1.3 astronomical units from the earth. It’s visible in Leo near the star Chertan. Vesta is the brightest of the asteroids, but still is at the limit of what the human eye can see unaided. On the 4^th, the moon rises in late evening, giving a few hours to see Vesta without interference from moonlight. You’ll see it easier as the moon rises later night after night.

The moon begins the month on the equator going south. Last quarter is on the 6^th. Southern lunistice is on the 7^th at 25.2°. New moon is on the 13^th and the moon goes north of the equator on the 14^th. First quarter is on the 21^st. Northern lunistice is on the 22^nd at 25.3°. The moon is full and on the equator going south on the 28^th.

Lunar perigee is on the 2^nd at 365,500 km. Apogee is on the 18^th at 405,300 km. A second perigee occurs on the 30^th at 360,200 km.

Notable conjunctions in March:

2^nd – Moon 6.0° from Spica

5^th – Mercury 0.3° from Jupiter, moon 5.0° from Antares

10^th – Saturn 3.6° from moon, Jupiter 3.9° from moon

11^th – Neptune 1.1° from sun, Mercury 3.5° from moon

19^th – Mars 1.9° from moon, moon 5.1° from Aldebaran

23^rd – Moon 3.4° from Pollux

26^th – Moon 4.4° from Regulus, Venus 1.4° from sun (superior conjunction)

29^th – Moon 5.8° from Spica