Four planets have conjunctions with the sun this month: Saturn on the 12th, Neptune on the 19th, Venus on the 23rd, and Mercury on the 24th. Of course, none of this is directly observable. But knowing that something is happening is a big part of the fun of astronomy.
This cluster of planets has been in our evening sky for the last several weeks. As March begins, Saturn’s barely an evening object and not likely to be observed by anyone on Earth. Mercury’s a little farther up at dusk. It’s climbing eastward among the stars and reaches greatest elongation on the 8th at 18.2° from the sun. Venus is coming from the other direction. They’re closest on the 12th at 5.5° separation. Brilliant Venus is easy to see. Mercury may require binoculars. Watch evening to evening as Mercury seems to decide that if Venus is heading sunward, it should too.
Venus will be easy to spot in the morning for some observers at the end of this month. You may have to wait until April to see Mercury and Saturn.
Partway up the western side of the sky dome at dusk is Jupiter, steadily moving eastward away from the Hyades. Similarly, Mars, a little higher than Jupiter, is steadily moving eastward out of the heart of Gemini. It spends this month slowly passing near Pollux.
In case this month’s planet watching doesn’t seem so exciting, maybe you’ll think it’s a great month for moongazing.
Moon phases this month: first quarter on the 6th, full on the 14th, last quarter on the 22nd, and new on the 29th.
Look at the moon every day or night that you can this month to get the most out of the greatest lunistices we can have for the next 18.6 years. Not only will the moon be at maximum declination, it will be at its maximum maximum declination. The moon starts the month over Earth’s equator on its way north. It reaches 28.7° north on the 7th. Try to observe how far north it is at moonrise, when it crosses the meridian,and at moonset. Every month for the next nine years, it will be just a little farther south. Then, month after month, the moon at maximum northern declination will be at little farther north again. Heading south, the moon crosses the equator again on the 14th. Then it reaches southern lunistice on the 22nd just as far south as it was north. And similarly to the northern declination, look how far south the moon is at moonrise, on the meridian, and moonset. The moon then heads north again to cross the equator on the 28th.
The maximum declination phenomenon we’re experiencing this month is called a major lunar standstill. Of course, the moon continues to move. But in the same sense that the sun stands still at solstice, the moon stands still at lunistice. And because of gravitational interactions that keep the moon’s orbit around the earth and Earth’s orbit around the sun from being perfect ellipses, Earth and the moon sort of wobble. So the moon’s maximum declination isn’t exactly the same every month. In nine years when the moon’s maximum declination reaches its minimum of 18.1°, that will be called a minor lunar standstill.
The moon is at perigee 362,000 kilometers away on the 1st. Apogee is on the 17th at 405,700 kilometers. A second perigee is on the 30th at 358,100 kilometers.
The moon passes in front of a few bright stars this month. El Nath is occulted on the 7th Universal Time. That will be on the evening of the 6th local time in Central America where the event is observable. On the 16th Universal Time, the moon passes in front of Spica. That’s visible in a region from eastern Africa, across the Indian Ocean, to far southwest Australia. Most of Australia and New Zealand get an occultation of Antares on the 20th Universal Time.
And there are two eclipses this month. A total eclipse of the moon happens on March 14 Universal Time. The penumbral phase starts at 03:57. Partial phase starts at 05:09. That’s when the moon begins to enter the central part of the moon’s shadow. It’s completely within the shadow from 06:26 to 07:31. The partial phase ends at 08:48 as the moon completely exits the central shadow. And then the penumbral phase ends at 10:00. Most of the Americas get the entire eclipse. It’s a moonrise event for most of Australia, far east Asia, and western Pacific islands. The moon’s setting during the eclipse for most of Africa, Europe, Iceland, Greenland, and part of South America.
And then, part of the earth gets a partial solar eclipse on the 29th. Eastern Canada and the far eastern continental United States get an eclipse at sunrise. So do part of the Atlantic Ocean stretching from there to the West Indies and French Guiana. As the moon’s central shadow goes too high over the Arctic to give anyone on Earth a total eclipse, partial phases will spread across Greenland, Iceland, western Europe, and far northwest Africa to to the northwestern part of Russia. Central Russia gets an eclipse at sunset. The place that gets the maximum eclipse is in Canada, a little inland from Hudson Bay, north of Puvirnituq, Quebec. Right as the sun rises there, it will be 93% hidden by the moon. People there and in that region will see a darker than usual dawn and a fiery red crescent come above the horizon.
Equinox is on the 20th at 09:02 UT.
Mercury’s at perihelion on the 4th, 45.9 million kilometers from the sun. Minor planet Ceres is at aphelion on the 25th at 446.7 million kilometers from the sun.