The Sun is at a standstill. Oh, it’s still orbiting the center of the galaxy at an impressive clip – about half a million miles per hour. And it’s still moving across the sky as Earth turns on its axis. But the points along the horizon at which the Sun rises and sets aren’t changing. That’s because today is the summer solstice. It’s a point in Earth’s orbit that marks the beginning of summer in the northern hemisphere and winter in the southern hemisphere. We have seasons because Earth is tilted on its axis. At the June solstice, the north pole tilts toward the Sun, bringing more sunlight to the northern hemisphere. Six months later, the south pole tilts toward the Sun, giving the northern half of the globe shorter days and longer nights. Between the solstices, the Sun moves north and south in the sky. So its rising and setting points move north and south as well. At some times of year, if you have a good way to mark these points, you can see the difference from day to day. But the Sun appears to “stand still” along the horizon for a few days on either side of the solstice. In fact, the word solstice means “Sun stands still.” At the June solstice, the Sun is farthest north for the year, so it rises and sets to the north of due west. Just how far north depends on your latitude. Incidentally, the summer solstice is also the longest day of the year, so there’s plenty of sunlight as we head into summer. Script by Damond Benningfield

The number of confirmed planets in other star systems has reached about 6,000. But few of those planets are likely homes for life. Most are too hot, too cold, too “gassy,” or they’re zapped by too much radiation by their star. A few planets are in the “well, maybe” category. They might be suitable for life, but the conditions aren’t perfect. An example is a planet in the star system 82 Eridani. The system is about 20 light-years from Earth, and its star is similar to the Sun. Astronomers have confirmed three planets in the system, with hints of more. Two of the planets are quite close to the star, so they’re too hot for life like that on Earth. But the third planet is more intriguing. It’s about six times the mass of Earth, so it could be dense and rocky. Its average distance from the star is about a third farther than Earth’s distance from the Sun. At that range, the planet spends most of its time in the star’s habitable zone – the region where conditions are most comfortable for life. But the planet’s orbit is so lopsided that the distance varies by more than a hundred million miles. So as the planet moves around 82 Eridani, surface temperatures range from hot enough to boil water to cold enough to freeze the entire surface. That makes it unlikely that anything lives on the planet. It is possible that life could exist below the surface – avoiding the extremes on this “yo-yoing” planet. Script by Damond Benningfield

Astronomers have been searching for planets around one of our closest neighbor stars for decades. And they’ve reported the discovery of several. But the reports have come to naught – until now. Earlier this year, a team confirmed the presence of four planets – all of them smaller than Earth. Barnard’s Star is six light-years away. Only the three stars of the Alpha Centauri system are closer. The star is much smaller and less massive than the Sun, and less than one percent as bright. In fact, it’s so faint that it wasn’t discovered until a little more than a century ago. Barnard’s Star is ancient – probably twice the age of the Sun or older. So if it has planets, there’s been plenty of time for life to take hold. That’s made finding planets a high priority. Last year, a team of astronomers confirmed one planet, and said there might be three more. All of those were confirmed in March. None of the planets is more than a third the mass of Earth. And they’re so close in that they orbit the star in a week or less. So even though Barnard’s Star is faint, the planets are all too hot to provide comfortable conditions for life. Barnard’s Star is in Ophiuchus, the serpent-bearer. The constellation stretches across the east and southeast in early evening, and stands high in the south later on. But Barnard’s Star is too faint to see without a telescope. We’ll have more about exoplanets tomorrow. Script by Damond Benningfield

If you stare at one of the giant planets of the outer solar system long enough, with a big enough telescope, you’re likely to find some moons. That was certainly the case a couple of years ago for Saturn. A research team scanned the space near Saturn with a large telescope in Hawaii. And earlier this year, the team reported its results: a haul of 128 previously unseen moons. That brought the planet’s total to 274. That’s three times the number of moons for second-place Jupiter – at least for now. The newly found moons are small and faint – no more than a few miles in diameter. They follow odd orbits, including some that orbit backwards – in the opposite direction from Saturn’s rotation. Some of the moons may be chunks of space rock that were captured by the giant planet’s gravity. Others may be the remains of larger moons that were blasted apart by collisions. About a third of the moons may be the remnants of a single impact. They form a group named Mundilfari for a Norse god related to Saturn. It’s possible the impact took place within the past hundred million years – adding lots of little moons to Saturn’s family. Look for Saturn near our own moon the next couple of mornings. The planet looks like a bright star. It’ll stand to the lower left of the Moon at dawn tomorrow, and closer to the right of the Moon on Thursday. Tomorrow: a passel of planets for a nearby star. Script by Damond Benningfield

If you sit on a big beachball, it gets mashed down. That makes it a little wider through the middle, and a little narrower from top to bottom. And that makes it look a lot like Alderamin, the brightest star of the constellation Cepheus the king. The star is about a third wider through the equator than through the poles. That’s not because some cosmic giant is sitting on it. Instead, it’s because the star spins like crazy. Alderamin is about 50 light-years away, so it’s a fairly close neighbor. It’s nearing the end of the prime phase of life, even though it’s billions of years younger than the Sun. That’s because it’s twice as massive as the Sun. Heavier stars “burn” through their nuclear fuel much faster than lighter stars. What really stands out about Alderamin, though, is its shape. The star’s equator rotates once every 12 hours, versus almost four weeks for the Sun. That forces gas outward around its middle, making the star look a bit more like a fat lozenge than a ball. As Alderamin continues to age, though, it will puff up to many times its current diameter. That will slow down its high-speed rotation, giving Alderamin a “rounder” appearance. Cepheus is in the north and northeast at nightfall. Under fairly dark skies it’s easy to make out. It looks like a child’s drawing of a house. The peak of the roof is on the left during the evening, with Alderamin marking the top right corner of the sideways house. Script by Damond Benningfield

Capricornus may be the most inventive constellation of the zodiac. For one thing, all of its stars are faint, so it takes some work to see any kind of pattern there. And for another, it represents the oddest creature in the heavens: a sea-goat – the front half of a goat plus the tail of a fish. It’s easy to find the sea-goat’s location early tomorrow, because the Moon passes quite close to its brightest star. Unfortunately, the Moon will overpower most of the nearby stars, so you might want binoculars to help you see them. The sea-goat’s leading light is known as Delta Capricorni or Deneb Algedi – the tail of the goat. It’s about 39 light-years away. It’s actually two stars locked in orbit around each other. The main star is twice the size and mass of the Sun, and about eight times the Sun’s brightness. The other star is smaller and fainter than the Sun. Twice a day, Delta Cap fades a bit. That’s because its stars orbit each other once per day. And they’re aligned in such a way that they eclipse one other during each orbit. The system dims a bit more when the faint star passes in front of the bright one, and a bit less when it’s the other way around. The stars of Capricornus form a wide triangle. Delta Cap is at the left point of the triangle. It climbs into good view by about 1 a.m. less than a degree from the bright Moon. Script by Damond Benningfield

A perfect spiral galaxy would include a bright, round “bulge” of stars in the middle; glittering spiral arms wrapping around it; dark lanes of dust lacing through the arms; and bright star clusters sprinkled about like lights on a Christmas wreath. In other words, it would look just like Messier 81, one of the best examples of a “grand design” spiral galaxy. It’s about 12 million light-years away, and appears close to the bowl of the Big Dipper. It’s a bit smaller and less massive than our own home galaxy, the Milky Way. M81’s “bulge,” though, is much larger and brighter than the one in the center of the Milky Way. And the black hole in the galaxy’s heart is almost 20 times as massive as the Milky Way’s. The spiral arms are outlined by the galaxy’s youngest, brightest stars. Over the past 600 million years or so, a major bout of starbirth has brightened the arms. That outburst is the result of gravitational interactions between M81 and two companion galaxies. The encounters compress big clouds of gas and dust. The clouds break into clumps, which then collapse to form stars – stars that make Messier 81 one of the most beautiful galaxies of all. Under clear, dark skies, you can spot M81 with binoculars. Find the Big Dipper, which is high in the north at nightfall. M81 hangs below the bowl at that hour. It looks like an oval smudge of light that’s almost as wide as the Moon. Script by Damond Benningfield

The stars look like they’re stuck in position – like fairy lights thumbtacked to a giant black canvas overhead. And over the course of a human lifetime – or many lifetimes – that’s true – there’s no way to see any motion without the help of sensitive instruments. But that’s only because the stars are so far away. Every one of those little lights is moving – fast. They’re all orbiting the center of the Milky Way Galaxy, for example. And they’re moving either toward or away from Earth. So over millions of years, the configuration of the stars changes – constellations come and go. And the pattern of brightness changes as well – some stars fade, others grow brighter. An example is Eltanin, the brightest star of Draco, the dragon. In fact, its name means “the great serpent.” It represents one of the dragon’s glowing eyes. Today, Eltanin is a bit more than 150 light-years away. But it’s moving more or less toward us at more than 60,000 miles per hour. On the scale of the galaxy, that’s tiny – but it adds up. In about one and a half million years, it’ll be just 28 light-years away. If the star doesn’t change much over that period, it could be the brightest star in Earth’s night sky. And it could maintain that rating for hundreds of thousands of years. Look for Eltanin high in the northeast at nightfall. It’s to the upper left of Vega, one of the brighter stars in the night sky – for now. Script by Damond Benningfield

Two fairly bright lights are headed for an especially close meet-up: the planet Mars and the star Regulus, the heart of the lion. They’re a few degrees apart tonight, but they’ll draw even closer over the coming evenings. Right now, Mars and Regulus are almost the same brightness. One way to tell them apart is their color – Mars looks pale orange, while Regulus is white with a hint of blue. Binoculars accentuate the colors. Another way to tell them apart is to look for them to twinkle. Regulus does, but Mars doesn’t. That’s because Mars is a bigger target in our sky. Regulus is thousands of times the size of Mars. But it’s so far away that we see it as nothing more than a pinpoint. That tiny beam of light is bent and twisted as it passes through the atmosphere. That causes the star to “twinkle.” It twinkles more when the air is more unsettled. Mars, on the other hand, is close enough that it appears as a tiny disk, made up of many pinpoints. Each one twinkles, but they even out. So Mars appears to hold steady as it shines through even the most un-steady skies. Look for Mars and Regulus about a third of the way up the western sky at nightfall. Regulus perches to the left or upper left of Mars. They’ll pass closest to one another on Monday and Tuesday. After that, they’ll move apart. At the same time, Mars will fade. A couple of weeks from now, Regulus will clearly outshine the Red Planet. Script by Damond Benningfield

Anchorage, Alaska, isn’t quite the “land of the midnight Sun.” Tonight, there are about five hours between sunset and sunrise. But it is a land of midnight sunlight, because twilight never completely fades. Twilight is the transition between day and night. Earth’s atmosphere scatters sunlight from the dayside to the fringes of the nightside. But when, exactly, does twilight end? When is the sky really dark? As you might expect, astronomers have their own definition. Astronomical twilight begins or ends when the Sun is 18 degrees below the horizon – about twice the width of your fist held at arm’s length. That’s when the sky’s as dark as it’s going to get. Because of the Sun’s motion, astronomical twilight lasts a minimum of about an hour and 10 minutes. But because the Sun usually rises and sets at an angle, twilight can last a good deal longer. During much of June and July, when the days are longest, twilight for much of the northern hemisphere lasts all night. The Sun never drops far below the horizon, so even though it’s out of sight, its light never disappears. So the people of Anchorage need some good blackout curtains to get a dark night’s sleep. If you want a few hours of darkness, head south – someplace like Miami Beach. It gets a full seven hours between evening and morning twilight – hours that might be illuminated by the neon lights of South Beach, but not by the Sun. Script by Damond Benningfield