Podcast for March 2022

I’m Kelly Beatty of Sky & Telescope magazine, and tonight we’re going on a tour of the stars and planets that you’ll see overhead during March. First we’ll celebrate the equinox; follow the Moon’s phases; figure out where all the planets have gone; learn about the Dog Star and his celestial neighbors; and dabble in some citizen science. So grab your curiosity, and come along on this month’s Sky Tour.

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When I hear “March,” I automatically think “equinox.”. This month it occurs on the 20th at 11:33 a.m. Eastern Time. Maybe you’ve heard this called the vernal or spring equinox, because, well, it signals the beginning of astronomical spring in the Northern Hemisphere. But likewise, it’s the start of autumn in the Southern Hemisphere. If you’ve listened to these monthly Sky Tours for a while — and I hope you have! — then you know that I sidestep this problem by always referring to the March equinox, the June solstice, and so on. Problem solved!
Now you’ve maybe noticed that the equinoxes and solstices don’t happen on the same date each year. For example, the March equinox can fall on the 19th, 20th, or 21st. Why is that? Well, a calendar year is 365 days long. But actually it takes Earth 365¼ days to circle the Sun — 365.256363004 days to be exact — and so those residual few hours add up. In any given year, the March equinox occurs 5 hours 49 minutes later than the previous year’s. Except during a leap year, of course, when it occurs 18 hours 11 minutes earlier than the previous year. Kind of makes my head hurt just thinking about it. 
Anyway, once March 20th rolls around those of us in the U.S. and Canada will have been on daylight time for more than a week, beginning on March 13th. But our European friends wait to begin their summer time until the 27th, and in most of Mexico the switch doesn’t occur until April 3rd. This must be a tough time of year to set up airline schedules!
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One thing that won’t make your head hurt this month is keeping track of the Moon’s phases. As we saw during February, during March the lunar phase and the calendar are pretty much in sync. New Moon comes on March 2nd, followed by First Quarter on the 10th, and Full Moon on the 18th. We round out the month with last quarter on March 25th, with the next new Moon to follow on April 1st. Easy peasy!
According to Native American lore, this month’s full Moon is known as the Full Worm Moon. That refers to the casts left on the ground by earthworms moving up through the softening ground. Another name, used by other tribes, is the Full Crow Moon, because the cawing of crows was thought to signal the end of winter. Other variations are the full Crust Moon, as in snow cover with a crusty top, or the Full Sap Moon. Since we usually have pretty brutal winters here in the Boston area, I have a new one to add: the Full Thawing Out Moon!
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Something is missing in the evening sky right now. Oh, there are stars aplenty, and I’ll get to those in a minute. But where have all the planets gone? Just a few months ago, you could take an early evening stroll and be dazzled by the views of Venus, Jupiter, and Saturn overhead. But that was then, and now you won’t find single naked-eye planet in the evening sky.
Instead, all of the action is in the morning sky before dawn. Now, to enjoy the predawn sky while it’s still dark, you’ll need to be up and outside by roughly 5 a.m. early in March. But after the switch to daylight or summer time, you can go out instead around 6. Not that early at all!
The two planets most easily seen are dazzling Venus, which rises in the east at least 2 hours before the Sun all month long. A few degrees to its lower right is Mars, which is much dimmer but still easy to spot. Then look for Saturn climbing out of the twilight glow. In early March it’s about 1½ times the width of your clenched fist at arm’s length to the lower left of Venus. But as the days go by, Venus seems to be frozen in the predawn sky as Saturn marches steadily upward and closes in on Venus. 
You might want to circle March 27th and, especially, the 28th on your calendar. On those mornings, this trio of planets will be joined by a lovely crescent Moon. In fact, on the 28th, Venus, Mars, Saturn and the Moon will be bunched so tightly that you’ll be able to cover all of them with one fist.
Now I haven’t mentioned Jupiter, have I? That’s because Jupiter is in conjunction with the Sun on March 5th. The dictionary defines conjunction as “an instance of two or more things occurring at the same point in time or space.” So if a total solar eclipse were to magically occur on the 5th, you’d see Jupiter right next to the Sun, just a finger’s width away. But sadly there’s no eclipse that day, and the Sun’s brilliant glow will keep Jupiter hidden from view until the first week of April at the earliest.
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If you’re not a “morning person,” don’t worry — a stunning array of stars awaits you after the Sun sets! As the twilight fades, turn left, away from the sunset point, until you’re looking south. There in the deepening blue, you’ll find the first true star of the evening: brilliant Sirius. It’s the brightest star in the constellation Canis Major, the Big Dog, and Sirius is known as the Dog Star. How early in twilight can you pick it up? Anytime during the first days of March, before the switch to daylight time, make a note of the horizon point directly below this beacon at 8 p.m. — that’s very nearly due south. Look in the star’s direction around 9 p.m. after the time switch. Sirius is the brightest star in the entire sky by a large margin (aside from our own Sun, of course), in part because it’s a close neighbor in space — just 8½ light-years away — and in part because it shines 25 times brighter than our Sun.
Sirius is the real “star” of the winter season. In fact, it’s bright enough that you can actually see it in the daytime sky — if you know where to look. Check out Bob King’s how-to article in the March issue of Sky & Telescope. 
And here’s something extra for those of you who live in the southern tier of the United States — from LA to Albuquerque to Oklahoma City to Memphis to Charlotte, and points south. Find Sirius in early evening, and look directly beneath it, close to the southern horizon. What is that bright star, you’re wondering? It’s called Canopus, and it ranks second, after Sirius, as the brightest star in the nighttime sky. It’s much farther away — 310 light years — but it outshines the Sun by more than 10,000 times. Canopus is always below the horizon for folks like me, who live farther north. So for you southern listeners, consider yourself lucky to be able to see it.
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After twilight ends, look to the upper right of Sirius to spot the mighty constellation Orion, the Hunter. Its two brightest stars are white Rigel, which marks Orion’s lower-right foot, and orange-red Betelgeuse, his upper-left armpit. Midway between them, look for the three-star row of Orion’s Belt. Draw a line through the Belt and follow it toward the right by about three fists, past the bright star Aldebaran, the eye of Taurus, until you reach a fuzzy little cluster of stars. That’s the Pleiades, or Seven Sisters, and they look fantastic through binoculars.
Now head back to Betelgeuse, and look to its left for Procyon, which sits in 8th place in the list of brightest stars. Procyon and Betelgeuse, together with Sirius, form a big, equilateral triangle in the sky — known as the Winter Triangle to skywatchers.
Let your eyes drift leftward, toward the eastern horizon. In the hours after sunset, that’s where you’ll find the constellation Leo, the Lion. The Lion’s alpha star, Regulus, sits at the bottom of a backward question mark that stretches toward upper left. Can you see it? That’s the lion’s head and mane. His hindquarters and tail are marked by a triangle of medium-bright stars to the lower left of Regulus. 
At this time of year, I think of Leo rising up in the east as a harbinger of spring — just like Orion’s climb a few months ago told me winter was coming. Look well to the upper left of Leo by about four fists, and you’ll spot another welcome sight in the early spring sky: the Big Dipper, seemingly balanced on the end of its handle.
Now look to the upper right of Leo, between Regulus and Procyon, and higher up, to locate a pair of bright stars stacked vertically and just a few degrees apart. These are creamy colored Pollux and icy white Castor, the twins of Gemini. They’re similar in brightness, so to tell which one is which, just remember that Pollux (with a P) is the one closer to Procyon. Castor, starting with C, is closer to the very bright star Capella, another C, that’s nearly overhead. The rest of Gemini’s twin bodies stretch out to the right, toward west.
Hey, after all that, give yourself a pat on the back. You’ve found Sirius, Capella, Rigel, Procyon, and Betelgeuse — 5 of the 10 brightest stars in the night sky — and 6 out of 10 if you spotted Canopus.
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Since you now know how to find Orion in the southwest and Leo in the east, I’d like you to make a special effort to view the mighty Hunter early in March and the mighty Lion during the last week of March. Why these particular dates? Well, for one thing the Moon won’t be in the sky — and so you’ll see the starry sky at its best. But it’s also when thousands of skywatchers around the world will be using the stars of these constellations to gauge how much light pollution they’ve got. It’s quick, easy, and fun — no telescope or special equipment is needed. Just go to the website globe-at-night.org, download the handy star charts there, match your view to the charts, and log in to record your observation.

That’s about it for this month. If you want more tips for viewing the night sky, including a free, interactive star chart for any time or date, check out our website, SkyandTelescope.com.
If you haven’t already subscribed, you can find Sky Tour on Apple Podcasts, Spotify, Stitcher, or wherever you listen. And please leave a rating or review! It will help others find the show. 
And if you want to explore the solar system and universe more deeply, please do check out the full line of binoculars and telescopes available at Celestron.com.
Sky Tour is a production of Sky & Telescope, a division of the American Astronomical Society, and is produced by me, Kelly Beatty. 
Next month I’ll introduce you to twin brothers who’ve really made a name for themselves in the sky. Until then, I wish you clear skies.