Podcast for August 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 August. First we’ll get ready for some awesome shooting stars, then tackle some puzzling Moon facts, watch Saturn climb in the eastern sky, and tour the stars of summer. Over the next 10 minutes, you’ll get a fun and factual roundup of “what’s up” the night sky. So grab your curiosity, and come along on this month’s Sky Tour.
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Let’s start with the Perseid meteor shower, one of the two best displays of “shooting stars” all year. These meteors are caused when little bits of grit, shed by a comet called Swift-Tuttle, slam into our atmosphere at 37 miles per second. Every August, like clockwork, we cross this comet’s orbit and plow right through all that dusty debris. 
Even casual skywatchers know about the Perseid meteor shower, because it can deliver at least one meteor per minute under pleasant summer skies. But the shower’s peak performance is relatively brief, so timing is important. For North Americans, this year the shower’s maximum should come on the night of August 12th and the predawn hours of the 13th. 
You don’t need any special equipment to enjoy the Perseids. But before you head out, grab a folding chair or one of those reclining loungers so you can lean back and look up without getting a sore neck. Take a long-sleeve shirt or light blanket too, in case it gets cool. And find a spot that’s far away from bright lights, with a clear view all around the horizon.
We call this shower the Perseids because the meteors all seem to radiate across the sky from the direction of the constellation Perseus, which is low in the northeast as evening twilight ends. This apparent point of origin, called the radiant, is actually just a trick of perspective, because the meteors themselves can appear anywhere in the sky. But . . . the higher the radiant is, the more meteors you’ll see. So theoretically you’ll see the best display in the hour just before dawn twilight, when Perseus stands nearly overhead in the sky. We’re talking 4 am here.
But you don’t need to stay out so late (or get up so early)! This shower can be enjoyed as soon as its radiant clears the horizon, by roughly 8 p.m. Unfortunately, just as the radiant is rising into view on August 12th, so too is the swollen Moon — just one day past full — which will flood the sky with its light. So that will cut down on how many meteors you’ll see.
But don’t despair! Here are some insider tips. First, more so than most showers, the Perseids produce many bright meteors, visible even when moonlight is strong. Second, keep an eye out for fireballs that skim Earth’s atmosphere soon after the radiant rises, creating long, dramatic streaks in the sky. Third, while the Perseids have a distinct peak, overall the shower is a fairly long one, so you can expect to see at least a few of these shooting stars for a few days before and after the 12th. And, fourth, you don’t need to look at the radiant to spot the Perseids. The best direction to watch is wherever your sky is darkest, and that’s usually straight up — or, this year, anywhere that blocks the Moon from view.
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Speaking of the Moon, it will be a very pretty crescent after sunset when this month begins. August’s full Moon falls on the 11th, and it’s known as the Full Sturgeon Moon, named after a freshwater fish that’s found in lakes and rivers in North America. But it’s also known as the Barley Moon, Grain Moon, or Fruit Moon. Last-, or third-quarter Moon comes on the morning of the 19th, followed by new Moon on August 27th. Then the Moon returns to the evening sky just as we flip the calendar to September.
Hey, have you ever wondered why full Moons have names but new moons don’t? Well, we say the Moon is new when it passes between Earth and the Sun. Around those times it gets thinner and harder to spot in the hours before dawn and then just disappears from view for a couple of days before emerging in the evening sky. So since we can’t see the Moon when it’s new, I guess there was no point in giving it distinctive monikers each month. Or we could start a new naming trend: the Not There Moon, Black as Coal Moon, etc.
Here’s another odd thing: Even as the Moon goes through its monthly cycle of phases, we always see the same half of its sphere. Huh? Why’s that? Well, the Moon is locked in the grip of Earth’s gravity in such a way that it makes one complete spin around its axis in exactly the same time it takes to orbit Earth. I know it’s a bit counterintuitive, but this spin-orbit resonance, the phrase that dynamicists use, keeps the same hemisphere of Moon constantly pointed toward Earth. 
Here's another way to think of it: Imagine you’re dancing with someone, and then you hold hands and spin around in circles. You’re always face to face, you never see each other’s back, and yet you are (both) turning around.
 It wasn’t until the Soviet Union’s Luna 3 spacecraft flew past the Moon, in 1959, that we had our first glimpse of the farside. Now, don’t be tempted to call the half we can’t see the “dark side.” Think about it: During new Moon, all of the half that’s facing us is in darkness, while the other half — on the farside — is the one basking in sunlight.
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On August 12th, while you’re waiting for that perfect Perseid to flash across the sky, do take a close look at the Moon. To its upper right, by about the width of your clenched fist held at arm’s length, is the planet Saturn. This month Saturn ends its long run in the predawn sky and officially becomes an evening-sky inhabitant. On the 14th, it reaches opposition, meaning that it’s opposite the Sun in the sky. So just as the Sun sets, Saturn is rising over the southeastern horizon. In the middle of the night, Saturn is its highest in the sky, and as dawn approaches it sinks from view in the west. 
Night by night, this beautiful planet will show up a little earlier and appear a bit higher up as twilight ends. Saturn is sitting in notoriously faint Capricornus, one of the 12 constellations of the zodiac. Capricornus is usually portrayed as a mythical beast that’s got the head of a goat and the tail end of a fish. But you won’t see anything like that in the sky, no matter how vivid your imagination! Instead, look for a broad triangular pattern kind of like the shape of a fat little rowboat, about two fists across the top. Saturn is near the upper-left corner.
 Not long after Saturn rises, it’ll be joined at lower left, 4 or 5 fists away, by much brighter Jupiter. The King of Planets is also edging toward opposition, in late September, and after that Saturn and Jupiter will be gracing our evening skies through the end of 2022. And if you’re up really late, after midnight for most of the month, keep an eye out for Mars rising in the east about as far to Jupiter’s left as Jupiter is from Saturn.
If you want a short-cut for finding these three planets, just keep track of the Moon. It’ll be close to Saturn on August 12th, near Jupiter on the 15th, and near Mars on the 19th. Easy-peasy!
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Let’s check out some of the stars you’ll see on these balmy summer evenings. As it starts to get dark, look well above where the Sun set, and you’ll easily spot Arcturus, the third-brightest star in the entire nighttime sky and the brightest star visible on summer evenings north of the equator. It’s the alpha star in the constellation Boötes, the Plowman. Let’s say that one together: boe-OO-teez. Got it? It’s derived from the Greek words for “to plow” and “ox.”
Look to the right of Arcturus, so that you’re facing roughly north. Once it starts to get really dark you’ll see the Big Dipper hanging from its handle about halfway up. At the end of the handle are four stars forming its bowl. You’ll find that your outstretched fist just covers the Bowl. Now draw an imaginary line through the bottom pair of stars and follow it toward upper right past the lip of the Bowl by about three fists until you reach a medium-bright star. That’s the North Star, called Polaris, and it shows you the direction toward due north.
Now go back to Arcturus, and this time slide your gaze well to the left and lower down until, a little to the west of due south, you reach Antares, the heart of the constellation Scorpius. Antares means “the rival of Mars,” and you should be able to notice that this star — like the planet — is slightly reddish. It’s an enormous red supergiant star about 550 light-years away.
Let’s try to make out the Scorpion’s shape. Look to the right of Antares for a trio of stars in a nearly vertical row. Those mark the Scorpion’s head. Sweep your gaze a little farther to the right for a pair of somewhat dimmer stars separated vertically by about one fist. The lower one is called Zubenelgenubi, the alpha star in the constellation Libra. The one higher up is called Zubeneschamali. These two stars traditionally mark the Scorpion’s pincers. In fact, their tongue-twisting Arabic names translate roughly as the Northern Claw and the Southern Claw. 
Now go back to Antares and look for a chain of fainter stars that trail down to its lower left and then hook upward and end with two stars very close together. That’s the critter’s long tail and stinger. For those of us in the Northern Hemisphere, the closer we live to the equator the higher up you’ll see the Scorpion in the sky. Those of you in southern states like Texas and Florida have much better views than I do way up in Massachusetts.
Shift your gaze due left of Antares, staying about the same height above the horizon, and look for a group of eight medium-bright stars in the shape of a teapot. The handle is on the left and the spout, tipped down a bit, is on the right. Got it? The whole thing is about the size of your clenched fist. From northern U.S. states and Europe, the Teapot is only a fist or two above the horizon, so it helps if you look from a spot with a clear, unobstructed view toward the south.
Now when astronomers carved up the sky they didn’t call this the Teapot constellation. Instead, you’ve found the main stars of Sagittarius, the Archer. And you are looking toward the center of our home galaxy. If you’re lucky enough to live where the sky is really dark, or if you happen to be on vacation in a rural setting, you’ll see puffs of steam coming up from the spout. Those puffs are the countless stars of the Milky Way, which continue upward until they arch overhead and clear across the summer sky.
And if you’re unlucky enough to live where light pollution is rampant, which is most of us, you can’t see the Milky Way at all. In fact, ask yourself: have you ever seen the Milky Way in all its glory? If not, you really owe it to yourself to get under a clear, deep-black sky this time of year to see all those stars streaming across the sky like a great river of light. It’s a sight you won’t soon forget.
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Thanks for letting me expand your celestial horizons for another 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.org.
If you haven’t already subscribed, you can find Sky Tour on Apple Podcasts, Spotify, Stitcher, or wherever you listen. And if you’ve enjoyed this episode, please leave a rating or review! It will help spread the word about Sky Tour, and I really welcome your feedback.
And if you want to explore the solar system and universe more deeply, 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 we’ll go exploring in and around the Summer Triangle. Until then, I wish you Clear Skies.