What’s up in March?

The month of March is named for Mars, the red planet and the Roman god of war. The planet itself is quite far away right now and not very impressive in the morning sky. But four major missions from four space programs around the world are scheduled to launch to Mars in July, so timed because Mars will reach opposition next Oct. 13. This is not the month of Mars, in other words, but it is the year of Mars.

For those of us who live in the northern hemisphere, March marks the return of spring. This year that will happen slightly earlier than usual, on March 19 at 11:50 p.m. This moment is further defined by the sun on the ecliptic crossing over the celestial equator as it ascends higher in our sky. The vernal equinox is one of only two days each year that the sun rises due east and sets due west for everyone on Earth except at the poles. Within a few days of both equinoxes, the days will also be exactly 12 hours long for everyone on Earth except at the poles — a natural, astronomical unifying effect for all of us.

I just returned from the Space Center in Houston for the annual Space Exploration Educators conference — three days of immersion in an out-of-this-world experience with 600 other teachers from around the globe. Many great speakers and astronauts gave presentations, but the heart of the conference was the more than 50 hands-on classes, all offering great resources and new and exciting ways to inspire others and to teach about space and its meaning.

A full-size space shuttle and Boeing 747 plane were parked outside the space center. You could tour these and get a better appreciation for the many benefits we’ve received between 1981 and 2011, a period during which NASA launched 135 space shuttles. We learned about the new Artemis (mythological sister of the Greek god Apollo) mission, which is scheduled to return us to the moon in just four years and establish an orbiting space station, to be named Gateway, around the moon.

The original Saturn 5 rocket that took us to the moon just over 50 years ago was also at the space center. I got some great pictures of it in the foreground with the full February supermoon rising through the pink belt of Venus and the purple shadow of the earth projected back to us from our atmosphere right above this great rocket. I toured the scale model solar system outside the space center one evening while waiting for an all-astronaut band named Max Q Music at Mach 25 (the speed at which the International Space Station orbits the earth) to perform for us. It was a perfect, balmy evening and sunset — 72 degrees with palm trees all around. I waited until I could see both inner planets, Venus and Mercury, in the evening sky with the Space Shuttle in the foreground silhouetted against a beautiful deep orange twilight sky.

Flying back to Maine, watching the sunset over the Rocky Mountains in Denver and the full supermoon, I calculated that I was flying about 35 times lower and 35 times slower than the space station, which has been orbiting above us for 20 years at 250 miles high moving at escape velocity, 17,500 mph.

Even though our winter hasn’t been very cold, still it is always nice to welcome back spring as our hemisphere once again tilts toward the sun. The nights will be getting shorter and warmer, and March offers many exciting highlights. These include a wonderful celestial dance of three bright planets in the morning sky as they trade places and form close conjunctions, Mercury briefly climbing back into the morning sky, Venus at its best in eight years in the evening sky and going through a close conjunction with Uranus, a bright asteroid named Vesta in Taurus the Bull, a comet named Pan-STARRS continuing to brighten, and the zodiacal light becoming visible well after sunset during the new moon later this month. Also keep your eye on Betelgeuse in Orion. It not only continues to get dimmer, it is now also changing shape, as noticed in a large telescope very recently. While it may not explode for another 1,000 years, it is getting more and more interesting.

Most of the action will take place in the morning sky, so it will be worth your while to get up early at least a few mornings to see this celestial dance. Mars, Jupiter, and Saturn start the month 19 degrees apart along the ecliptic in the morning sky one hour before sunrise. Then Mars will cruise past both gas giants, forming a close conjunction with Jupiter less than 1 degree apart on the 20th and another one with Saturn on the 31st. The waning crescent moon will be just 2 degrees from Mars and Jupiter two days before their first conjunction. All three planets are still in their normal, eastward, or prograde motion through the sky against the fixed background of stars. Jupiter and Saturn will not reach opposition until July. Keep watching as Mercury joins the trio by the middle of this month.

Venus will glide within 2.2 degrees of Uranus on the 8th and 9th. Technically speaking, at 5.9 magnitude, Uranus should be visible without binoculars, and maybe it would be under absolutely perfect conditions. Practically speaking, though, you will probably need the binoculars to see this strange planet, which orbits tilted on its side. Uranus is 24 times farther away than Venus and just over 10,000 times fainter than our brightest planet.

Vesta will track through Taurus all month. At 320 miles in diameter, it is our second largest asteroid, right after Ceres at 600 miles in diameter. Together, the four largest asteroids make up about half of all the mass of the over 900,000 asteroids we have counted in the belt between Mars and Jupiter. Vesta reflects 40 percent of all the sunlight that hits it and is the source of most of the meteorites that hit the earth. It will reach 8.5 magnitude.

Comet Pan-STARRS will continue to brighten as expected as it cruises through Cassiopeia this month. It is ninth magnitude now, and it may become visible to the naked eye by May when it will be at its closest for this orbit.

The zodiacal light can be best seen during the two narrow windows each year when the angle of the ecliptic is the steepest with our horizon. Those occur in November before sunrise and in March about an hour and half after sunset. The light is created by sunlight bouncing off countless tiny particles of comet dust, which were left there over the eons by long-since-faded ancient comets. It actually forms a torus all around the ecliptic plane, but we can only see it as a cone or pyramid of ghostly light. It is aligned with our orbital plane and now passes through Pisces, Aries, and Taurus.

MARCH HIGHLIGHTS
March 2: First quarter moon is at 2:57 p.m.
March 9: Venus passes within 2 degrees of Uranus. Full moon, also known as the Crow, Worm, Lenten, or Sap Moon, occurs at 1:48 p.m.
March 10: The moon is at perigee, or closest to Earth, at 221,905 miles at 2:30 a.m.
March 13: In 1781, Sir William Herschel discovered the planet Uranus. On the eighth, Venus will glide by Uranus, 239 years after its discovery. At 84 years per orbit, Uranus has completed fewer than three orbits since its discovery.
March 14: Albert Einstein was born on this day in 1879. His general theory of relativity (1915) completely redefined gravity as simply the topography of the fourth-dimensional space-time continuum.
March 16: Last quarter moon is at 5:34 a.m. Caroline Herschel was born on this day in 1750. She worked closely with her brother (Sir William) and discovered eight comets on her own.
March 18: The moon passes near Mars, Jupiter and Saturn this morning.
March 19: The vernal equinox is at 11:50 p.m.
March 20: Mars passes 0.7 degrees south of Jupiter this morning.
March 24: New moon is at 5:28 a.m. Venus is at its greatest eastern elongation from the sun this evening and exactly half lit.
March 28: The moon passes near Venus this evening.
March 31: Mars passes less than 1 degree south of Saturn this morning.