Skywatch Line for Friday, March 7, through Sunday, March 9, written by Sam Salem

This is Dudley Observatory’s Skywatch Line for Friday, March 7, through Sunday, March 9, written by Sam Salem.

On Friday, Sun rises at 6:21am and sets at 5:52pm; Moon sets at 2:32am and rises at 10:50am.

Daylight saving time starts on Sunday at 2:00am. Turn you clock forward 1 hour.

Watch four planets in the evening sky. They will lie along the path the Sun travels in daytime. First, look for Venus and Mercury about 40 minutes after sunset. Then as darkness falls, look for bright Jupiter high overhead and reddish Mars high in the eastern sky. Venus and Mercury set soon after sunset, but you can catch Jupiter and Mars until after midnight.

Venus will shine in the east about 40 minutes after sunset on Friday, near Mercury. Mercury will reach its greatest distance from the Sun on Saturday.

Although Venus lies a respectable 30° from the Sun at the beginning of the month, it appears low in the sky. The low altitude arises because the ecliptic, the Sun’s apparent path across the sky that the planets follow closely, makes a shallow angle to the western horizon after sunset at this time of year. Venus quickly disappears in the twilight glare as it heads toward inferior conjunction March 23. It will return to view before dawn in April.

The waxing gibbous Moon will lie near Mars on Friday. The twin stars of Gemini, Castor and Pollux are also nearby. On Saturday evening, the Moon will float close to Mars and the twin stars of Gemini. 

Mars is visible all night and stands high in the east at sunset, located in central Gemini. It forms a nice triangle with Gemini’s brightest stars, Castor and Pollux. The Red Planet continues to dim this month. It shines at magnitude –0.3 on March 1st. and dims to magnitude 0.4 by the 31st.

Jupiter and Mars continue their march westward among the evening stars, closer to overhead. Find Jupiter about one-third of the way from the northwestern horizon to the zenith as twilight ends, shining among the background stars of Taurus the Bull.

Saturn reaches conjunction with the Sun on March 12 and remains out of sight all month.

Orion stood at his highest in the south in early evening in the month of February. Now Orion has moved westward and his dog, Canis Major with Sirius on his chest, stand center stage on the meridian. Sirius is not only the brightest star in our sky after the Sun, but also the closest naked-eye star after the Sun, at 8.6 light-years, seen from mid-northern latitudes. Alpha Centauri is the actual closest star at 4.3 light-years, but you have to be farther south to see it. In the northern sky three dim red-dwarf stars are closer to us than Sirius, but these require binoculars or a telescope. These three dwarf stars are in the constellations of Ophiuchus, Libra, and Virgo.