There are lots of exciting things happening in this stargazer’s guide to March 2018 — including two full Moons, several planetary line ups, and more! Here’s the full calendar of astronomical events happening in March 2018. Bookmark this page so you don’t miss a thing!
March is especially exciting as for the first three weeks of this month, the two “inferior” planets, Mercury and Venus, will be within 5-degrees of each other. Search for them low above the western horizon about a half hour after sunset. While both should be evident to the naked-eye, binoculars will certainly enhance their visibility against the bright twilight.
All times Eastern, for the Northern Hemisphere:
March 1—The Full Worm Moon at 7:51 p.m. In this phase, the visible Moon is fully illuminated by direct sunlight. Though the Moon is only technically in this phase for a few seconds, it is considered “full” for the entire day of the event, and appears full for three days. See how this full Moon got its many names in this short video:
March 4—With the moon rising later in the night there is a greater opportunity for the zodiacal lights to be seen over the next two weeks. Find these lights shimmering in the west.
March 7 – During the predawn hours, the waning gibbous Moon will pass about 3½-degrees above the brilliant planet Jupiter. This giant planet rises in the east-southeast around 11:45 p.m. at the beginning of March, and around 10:45 p.m. at month’s end. The brightening world shines near magnitude -2.3 as it slowly begins to retrograde (move westward relative to the stars) on the 9th. Telescopic observers will want to wait until Jupiter is good and high, starting around four hours before sunrise.
March 9 – Last Quarter Moon at 6:20 a.m. In this phase, the Moon appears as a half Moon in the sky. One-half of the Moon is illuminated by direct sunlight while the illuminated part is decreasing, heading toward the “New” (invisible) phase.
March 10— Just before 2 a.m. local time, look low near the east-southeast horizon for the rising of a fat waning crescent Moon and about 4½-degrees to its right, a bright reddish-orange “star” which in reality is the planet Mars. The red planet rises about four hours before the Sun, crossing the meridian shortly after sunrise. It moves from Ophiuchus into Sagittarius in March and by month’s end it’s passing north of the Teapot. Mars begins March at magnitude +0.8, but brightens noticeably to magnitude +0.3 by the end of March; an artifact of its slow, steady approach to the Earth. From a distance of 130 million miles on the 1st, it will be 104 million miles away by 31st!
March 11 – Check out the southeast sky a couple of hours before sunrise to see a lovely crescent Moon and about 5° to its right you’ll see a bright “star” shining with a steady yellow-white glow. That will be Saturn. The famous ringed world rises in the early morning hours and is fairly well placed for observing just before dawn.
March 11 – Moon at apogee at 5:17 a.m., its farthest distance from Earth in its orbit.
An easy way to remember: (A)pogee = Away
March 15 – Look to the western horizon after sunset to see Mercury and Venus paired up.
March 17 – New Moon at 9:12 a.m. In this phase, the Moon is not illuminated by direct sunlight and is completely invisible to the naked eye.
March 18 – About 45 minutes after sunset, look low toward the western horizon to sight an extremely narrow (2-percent) crescent Moon. About 4-degrees to its upper right shines Venus, and a similar distance to Venus’ upper right will be Mercury, still shining at a respectably bright +0.4.
March 24 — First quarter Moon at 11:35 a.m. In this phase, the Moon looks like a half-Moon in the sky. One-half of the Moon is illuminated by direct sunlight while the illuminated part is increasing, on its way to full.
March 26 – The Moon is at perigee,at 1:26 p.m., which means that it is at the closest point to Earth in its cycle.
March 28 – The planets Venus and Uranus are in close conjunction, the second-closest of all of 2018 (the conjunction of Mars with Neptune on December 7, 2018, will be closer). Venus passes only 4 minutes of arc (0.066-degree) south of Uranus – that’s equal in apparent dimensions to almost twenty-three Venus disk diameters. Least separation between the two planets will take place at 8:47 p.m. Eastern Daylight Time. For western time zones the Sun will still be up, but the two planets will still be nearly as close when darkness arrives. The only drawback is that you’ll have to wait until the background twilight sky has sufficiently darkened for you to sight Uranus. Wait until about an hour after sundown, but be aware that by that time the planet duo will be very low – only about 6 degrees above the western horizon.
March 31 – A full Blue Moon at 8:37 a.m. A “Blue Moon” occurs when there are two full Moons within a calendar month. The term is also has another definition — it’s also used when there are four moons in a season; the third of these is referred to as a “Blue Moon.”