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  • The mild nights of spring are generally a good time for skywatching. Only one thing is missing: a great meteor shower. The really good showers are clustered in fall and winter, with the Perseids of August sometimes joining the list. Although the season doesn’t offer a great shower, a pretty good one is at its peak tomorrow night: the Lyrids. Under a dark sky, you might see up to a couple of dozen meteors per hour between midnight and dawn. The number of meteors increases closer to dawn, as your part of Earth turns into the meteor stream. Unfortunately, by then the last-quarter Moon will be in the sky, so its light will compete with the fainter meteors. One good thing about meteors, though, is that you don’t have to wait for a shower to see them. A shower occurs when Earth passes through a stream of small bits of rock shed by a comet or asteroid, which happens a few times a year. But other bits of rocky debris are scattered throughout the solar system. So on any dark night you can see several meteors zipping across the sky. And unlike the meteors in a shower, which all appear to “rain” into the sky from the same general point in space, these “random” meteors can come from any direction and blaze across any part of the sky. So if you have a chance, look for the Lyrid meteor shower in the wee hours of Tuesday morning. If not, then take advantage of just about any clear, dark night to look for meteors flashing across the heavens.   Script by Damond Benningfield, Copyright 2014 For more skywatching tips, astronomy news, and much more, read StarDate magazine.      Related StoriesBear’s Lodge - EnclosureChanging Skies - EnclosureBear’s Lodge 

  • If Gallup took a poll to find the best-known star pattern in the night sky, the odds are the winner would be the Big Dipper. Perhaps surprisingly, though, the dipper isn’t a constellation. Instead, it’s an asterism — a star picture that may be a part of a constellation, or that may not be related to any constellation at all. The stars of the dipper, for example, are part of Ursa Major, the great bear — they represent the bear’s body and tail. But the bear incorporates many other stars besides the dipper — and a dipper has little to do with a bear. But in some cultures, there’s a link between bears and the seven stars of the Big Dipper. A Kiowa story, for example, says that eight children — seven sisters and a brother — were playing at the edge of the Black Hills one day. The boy was suddenly struck by powerful magic. He was transformed into a bear and began to chase his frightened sisters. A tree called to them, and when they climbed into its branches it grew to an enormous size. The angry bear scratched and clawed at the tree, gouging deep grooves in its bark. But the sisters were borne safely into the sky, where they became the stars of the Big Dipper. The petrified stump of that mighty tree is known as the Bear’s Lodge — the Kiowa name for a stump-like mountain in Wyoming that’s also known as Devil’s Tower. Each night, the sisters look down upon it — from the safety of that most popular of star pictures, the Big Dipper.   Script by Damond Benningfield, Copyright 2014 For more skywatching tips, astronomy news, and much more, read StarDate magazine.      Related StoriesBright and Fast - EnclosureBright and FastChanging Skies 

  • Most of the world’s major observatories stand on remote mountaintops, far from the pesky glow of city lights. So as twilight fades away this evening, their skies will be speckled with an amazing richness of twinkling stars. And their telescopes have a clear shot at even more amazing sights — from stellar nurseries and the remains of dead stars to the feeble glow of distant galaxies. By shortly after midnight, though, those skies will look a good bit murkier — thanks to the Moon. Sunlight is illuminating more than 80 percent of the lunar hemisphere that faces our way, so the Moon shines brightly. Molecules of air scatter the moonlight, filling the sky with a faint glow — a weaker version of daylight. During the daytime, the air molecules scatter sunlight — especially bluer wavelengths, which is what makes the sky look blue. But the Sun is about 800,000 times brighter than the Moon is tonight, so the effect is much more dramatic — the stars are completely obliterated from view. Even so, there’s enough moonlight to cause astronomers to change their viewing tactics. Since they can’t see faint stars and galaxies when there’s a bright Moon in the sky, they instead look at brighter objects, which still shine through. And they must carefully calibrate their observations to subtract the effects of the moonlight. Still, there’s plenty for the casual skywatcher to see, as bright stars and planets shine through the Moon’s hazy veil.   Script by Damond Benningfield, Copyright 2014 For more skywatching tips, astronomy news, and much more, read StarDate magazine.      Related StoriesNorth Galactic Pole - EnclosureNorth Galactic PoleMoon in the Middle - Enclosure 

  • Thousands of galaxies of all sizes, shapes, and distances congregate in this newly released Hubble Space Telescope image. Some of the small, red galaxies are perhaps 10 billion light-years away or farther, while some of the larger ones are much closer. The image includes a prominent gravitational lens (bright white ring to the lower left of center), in which the gravity of two large galaxies is bending and magnifying the light of a distant quasar. The image was compiled over 14 hours of observations in both optical and infrared wavelengths. [NASA/ESA] Text ©2014 The University of Texas at Austin McDonald ObservatoryFor more skywatching tips, astronomy news, and much more, read StarDate magazine.      Related StoriesNorth Galactic Pole - EnclosureNorth Galactic PoleRunaway Stars - Enclosure 

  • The heart of the scorpion is doomed. Sometime within the next million years or so, the star Antares is likely to blow itself apart as a supernova. Only its tiny, dead core will remain — a neutron star. That same fate awaits several other bright stars in Scorpius, including one that’s quite close to the Moon tonight. Acrab is to the right of the Moon as they climb into view after midnight, at the end of a short line of three stars that represents the scorpion’s head. Acrab is actually a stellar sextuplet. It consists of two tight pairs of stars, each of which has a distant companion. The two triplets are then bound to each other as well, giving Acrab six stars in all. Two of those stars appear to be at least 10 times as massive as the Sun. That’s above the weight limit that determines which stars will explode as supernovae. So within a few million years, the cores of each of these stars probably will collapse, and their outer layers will blast into space. For a few weeks, each explosion will shine as brightly as billions of normal stars. After that, the stars will fade from sight. For now, though, Acrab remains in good view. Look for it just to the right of the Moon after midnight. Much brighter Antares, the orange star that marks the scorpion’s heart, stands below them. And an even brighter pinpoint of light — the golden planet Saturn — is farther to their upper right. The whole tableau is low in the southwest at first light.   Script by Damond Benningfield, Copyright 2014 For more skywatching tips, astronomy news, and much more, read StarDate magazine.      Related StoriesSupernova Factory - EnclosureSupernova FactoryOutbursts - Enclosure 

  • The Moon and the planet Saturn stage quite a performance tonight. They rise in late evening, with bright golden Saturn quite close to the upper left of the Moon. They remain close as they arc low across the south during the wee hours of the morning, with Saturn moving to the right of the Moon at first light. Saturn has quite a collection of moons of its own. More than 50 have been confirmed, with several more on the list of possibilities. Some of these moons are fascinating worlds in their own right. Titan, the largest of them, has a dense, cold atmosphere made of hydrocarbons. Lakes of liquid methane and ethane dot its surface, and an ocean of liquid water may lie far below Titan’s icy crust. Liquid water also lies beneath the crust of Enceladus, which is near the outer edge of Saturn’s rings. But some of its water escapes into space through powerful geysers near the moon’s south pole. The water freezes, adding fresh ice to one of the rings. These moons probably formed along with Saturn itself. But many of the planet’s moons may be asteroids that were captured when they flew close to Saturn. Such a capture would have been easier early in Saturn’s life, when it was likely encircled by gas and dust left over from its formation. Friction with this material slowed the asteroids, allowing them to enter orbit — adding to Saturn’s impressive entourage of moons. We’ll talk about the Moon and more bright companions tomorrow.   Script by Damond Benningfield, Copyright 2014 For more skywatching tips, astronomy news, and much more, read StarDate magazine.      Related StoriesGiving Birth?Bright and FastMoon and Saturn - Enclosure 

  • A bright streak at the bottom of Saturn's rings may be caused by a small, icy moon that is growing as it captures more ice particles from the rings. The scientists who discovered this possible moon, nicknamed "Peggy," say it could be migrating out from the rings, scattering ring particles in its path. The Cassini spacecraft snapped this image on April 15 at a distance of about 775,000 miles (1.2 million km). [NASA/JPL/SSI] Text ©2014 The University of Texas at Austin McDonald ObservatoryFor more skywatching tips, astronomy news, and much more, read StarDate magazine.      Related StoriesMoon and Saturn - EnclosureMoon and Saturn 

  • The star patterns that form pretty pictures in the night sky are all temporary. Over time, their shapes will change, erasing the old pictures and creating new ones. It’s not something that’s visible in a human lifetime — or, with a few exceptions, in a hundred lifetimes. One of those exceptions is Arcturus, one of the brightest stars in the night sky. The yellow-orange star is in the east as the sky gets good and dark, well to the upper left of the Moon. Don’t confuse it with the brighter orange light that’s above the Moon — the planet Mars. One reason Arcturus shines so brightly is that it’s a close neighbor — just 37 light-years away. In fact, it’s about as close right now as it ever will be. Arcturus is racing across the sky at about 270,000 miles per hour relative to our own solar system — roughly the distance from Earth to the Moon. That’s faster than any of the other especially bright stars in the night sky. As a result of that motion, Arcturus will fade from view in a hurry — astronomically speaking. A million years from now it’ll be lost from view. In the meantime, its motion will drastically alter the pictures of a couple of constellations. Today, Arcturus is the leading light of Bootes, the herdsman. But 50,000 years from now it’ll have moved one constellation over, and will be shining near the bright star that lines up between the Moon and Mars tonight — Spica, the leading light of Virgo.   Script by Damond Benningfield, Copyright 2014 For more skywatching tips, astronomy news, and much more, read StarDate magazine.      Related StoriesRunaway Stars - EnclosureRunaway StarsLunar Eclipse - Enclosure 

  • Tonight is one of the best skywatching nights of the year. The planet Mars blazes through the night like a brilliant orange beacon, with the bright star Spica nearby. But what really elevates the night is a total lunar eclipse, which takes place just a few degrees away from Mars. The eclipse occurs as the Moon passes through Earth’s long shadow. The Moon’s orbit is tilted a little, so most months the Moon passes outside the shadow. This month, though, the geometry is just right, creating a total eclipse. The Moon first touches the dark inner shadow at 12:58 a.m. Central Daylight Time. Over the following hour, the shadow will appear to take a bigger and bigger “bite” out of the lunar disk. The Moon will be fully immersed by 2:06, and will remain totally eclipsed for almost an hour and 20 minutes. Sunlight filtering through Earth’s atmosphere usually gives the eclipsed Moon a dark orange or red color, although your ability to see it depends on your viewing conditions and your color sensitivity. The Moon will exit the shadow, bringing the partial eclipse to an end, a little more than an hour later. And to add to the night sky’s entertainment, the star Spica huddles quite close to the Moon. At their closest, they’ll be separated by just a degree or so — the width of your finger held at arm’s length. Spica will look a bit pale next to the uneclipsed Moon, but should be especially beautiful as the eclipse unfolds.   Script by Damond Benningfield, Copyright 2014 For more skywatching tips, astronomy news, and much more, read StarDate magazine.      Related StoriesLunar EclipseNorth Galactic Pole - EnclosureNorth Galactic Pole 

  • If the Moon’s orbit around Earth were aligned just a little differently, human history might have played out a little differently, too. That’s because eclipses of the Sun and Moon have played pivotal roles in some historical events. Lunar eclipses occur when the Moon passes through Earth’s shadow, while solar eclipses occur when the Moon crosses in front of the Sun, blocking it from view. But the Moon’s orbit is tilted with respect to Earth’s orbit around the Sun. So most months, the Moon, Sun, and Earth don’t line up properly to cause an eclipse. The geometry is right only a few times per year, so any given location on Earth sees a total lunar eclipse every year or so, and a total solar eclipse every few decades. Because eclipses are rare, they were hard to predict — and that made them scary. In 413 BC, for example, the army of Athens suffered a major defeat when it delayed retreating after a lunar eclipse. And two millennia later, Christopher Columbus and his men avoided starvation when Columbus accurately predicted another eclipse, causing hostile natives in the New World to bring them food. If the Moon’s orbit were perfectly aligned with the Sun, though, then eclipses would be so common that they would have attracted far less concern — perhaps changing the course of history. An eclipse will darken the Moon tomorrow night. A nearby star and planet will help make it an unforgettable experience — which we’ll talk about tomorrow.   Script by Damond Benningfield, Copyright 2014 For more skywatching tips, astronomy news, and much more, read StarDate magazine.      Related StoriesLunar Eclipse - EnclosureMore Lunar Eclipse - EnclosureMore Lunar Eclipse 

  • Our home galaxy, the Milky Way, is shaped like a giant pancake. On dark nights, away from city lights, you can see the outline of that disk as the hazy band of light known as the Milky Way. Tonight, with the help of a bright star, you can gaze straight up and out of the disk — deep into intergalactic space. One of the two points where we look perpendicular to the Milky Way's starry disk is called the north galactic pole. It has nothing to do with the North Star, which is above Earth's north pole, marking the north celestial pole. Unfortunately, no bright star marks the galactic pole, which is in the faint constellation Coma Berenices. But you can still find the galactic pole’s rough position thanks to the bright orange star Arcturus. Arcturus is the fourth-brightest star in the night sky. Look for it in the east as night falls. If you need help finding it, just look for the Big Dipper. Follow the curve of the dipper’s handle away from the bowl, and you’ll “arc to Arcturus.” Now, to find the north galactic pole, look just a little to the west of Arcturus. There, you’ll be gazing nearly straight out of the Milky Way’s disk of stars, into a universe of galaxies. In fact, the two best-known galaxy clusters — the Virgo cluster and the Coma cluster — lie quite close to the galactic pole, so this part of the sky often attracts astronomers who study galaxies beyond our own. Tomorrow: getting ready for a lunar eclipse.   Script by Ken Croswell, Copyright 2014 For more skywatching tips, astronomy news, and much more, read StarDate magazine.      Related StoriesChanging Skies - EnclosureChanging SkiesNorth Galactic Pole - Enclosure 

  • A total lunar eclipse will grace skies across the United States several hours before dawn on Tuesday, April 15, according to the editors of StarDate magazine. read more       

  • Like young birds that are leaving their nests for good, a few stars are taking wing from their galactic nest. They’re moving so fast that they’ll eventually escape from the Milky Way and head into the vastness of intergalactic space. They’re known as “hypervelocity” stars. They’re moving more than a million miles per hour faster than the other stars in the galaxy. And they seem to come in two varieties. One consists of hot, heavy stars that were kicked out of the galaxy’s core. The other consists of stars that are similar to the Sun residing away from the core. The first group was discovered almost a decade ago. These stars originally had stellar companions. These systems passed close to the supermassive black hole at the galaxy’s heart. A gravitational dance resulted in one of the stars being captured by the black hole, with the other getting a kick powerful enough to propel it out of the galaxy. The second group was discovered just last year. A team of astronomers looked at a survey of hundreds of thousands of stars. The study revealed about 20 stars moving fast enough to escape the galaxy. Unlike the other group, though, these stars appeared to come from the galaxy’s disk, well outside the core. All of the stars are similar to the Sun. There’s no obvious way for these stars to get a strong enough kick to leave the galaxy behind. That leaves the astronomers with a mystery to solve — the mystery of the runaway stars.   Script by Damond Benningfield, Copyright 2014 For more skywatching tips, astronomy news, and much more, read StarDate magazine.      Related StoriesRunaway Stars - EnclosureMoon and Saturn - EnclosureMoon and Saturn 

  • Powerful winds and radiation from a pulsar (bright dot at center of green and purple cones) heat and erode a companion star in this artist's concept. Over time, this process may completely evaporate the companion. The pulsar spins rapidly, emitting beams of energy (the colored cones) that can be seen from Earth as pulses of energy. [NASA/GSFC/Cruz deWilde] Text ©2014 The University of Texas at Austin McDonald ObservatoryFor more skywatching tips, astronomy news, and much more, read StarDate magazine.      Related StoriesBlack Widow Pulsars - EnclosureBlack Widow PulsarsMoon and Saturn 

  • Black widows lurk among the stars. They slowly destroy their companions, ingesting part and sweeping away the remains. These nasty-sounding objects are pulsars — the spinning corpses of once-mighty stars that blasted themselves apart. All that’s left is their crushed cores, known as neutron stars. Some neutron stars spin, emitting beams of energy that sweep across the cosmos like a lighthouse. From Earth, we see such a beam as on-and-off pulses — hence the name “pulsar.” Some pulsars have companions — “normal” stars like the Sun, or perhaps the “failed” stars known as brown dwarfs. Radiation from the pulsar heats the companion, causing it to puff up and lose its grip on the hot gas at its surface. Some of the gas is pulled in by the pulsar, causing it to spin faster — up to hundreds of times per second. But pulling material off the surface of its companion is only half of the story of a black widow. In some cases, the pulsar’s radiation also erodes the surface of its companion like a blowtorch, with gas streaming away from the pulsar. Over time, the combination of accretion — pulling material into the pulsar — and erosion — blasting stuff away from the pulsar — can completely destroy the companion. So far, astronomers have caught only a handful of black widows in the process of destroying their companions. But they suspect that many more have already finished the deed — dead stars that have devoured their mates.   Script by Damond Benningfield, Copyright 2014 For more skywatching tips, astronomy news, and much more, read StarDate magazine.      Related StoriesBlack Widow Pulsars - EnclosureDoomed MateMoon and Saturn 

  • Living on Mars won’t be easy. Explorers will be challenged by radiation, extreme cold, prickly dust, and the danger of obliteration by space rocks. The Martian atmosphere is quite thin, so it doesn’t hold in much heat. Combined with Mars’s distance from the Sun, that makes the planet extremely cold. And the atmosphere and magnetic field do little to screen out radiation from the Sun and beyond. Those challenges could be handled by covering a habitat with a layer of Martian dirt, which would keep the heat in and the radiation out. Yet the dirt itself is another challenge. It’s quite fine, so it would be tough to filter out. It could cause respiratory problems, and short out electrical equipment. The thin Martian air presents another problem: It lets a lot of space rocks hit the surface. On Earth, all but the largest space rocks either burn up or explode high in the atmosphere. But on Mars, many more rocks survive to hit the surface. Last year, for example, a Mars-orbiting spacecraft discovered an impact crater that had been gouged sometime during the past three years. The crater is about a hundred feet across, and the impact blasted debris for miles in every direction. So anything within a few miles of the impact likely would have been destroyed by the shockwave or falling debris — one more hazard for Mars explorers. And Mars is putting in its best showing of the year. It looks like a brilliant orange star, and is in view all night.   Script by Damond Benningfield, Copyright 2014 For more skywatching tips, astronomy news, and much more, read StarDate magazine.      Related StoriesNorth Galactic Pole - EnclosureMars at Opposition III - EnclosureMore Lunar Eclipse - Enclosure 

  • Low fog fills a Martian canyon in this artist's concept of future Martian exploration, while frost coats the canyon rim. A Mars-orbiting spacecraft is being retargeted to watch early mornings on the Red Planet to learn more about fog, low clouds, and frost observed by previous missions. [NASA] Text ©2014 The University of Texas at Austin McDonald ObservatoryFor more skywatching tips, astronomy news, and much more, read StarDate magazine.      Related StoriesNorth Galactic Pole - EnclosureNorth Galactic PoleMars at Opposition III - Enclosure 

  • Sunrise on Mars often sees frost and patches of fog and low clouds. They usually disappear by noon. But details of these cold, gray mornings remain unclear. How the fog and clouds form, and where and what times of year they’re most common are a bit...well, foggy. A spacecraft may soon shine a little more light on those questions. It’s being moved to a new position that’ll allow it to view early morning conditions for half of each orbit around Mars. The maneuver began in February, but won’t be completed until November of next year. Odyssey is the longest-operating Mars spacecraft — it arrived at the Red Planet in 2002. It orbits from pole to pole. It’s been synchronized so that for half of its orbit it’s seeing the ground at 4 to 5 p.m. local time. The other half of the orbit is before sunrise. Sunrise conditions have received little attention from any Mars orbiter. A few observations by those orbiters — as well as from landers and rovers — show that morning frost, fog, and clouds are fairly common. Odyssey’s new orbit will allow scientists to study these conditions in much more detail — filling in some gaps in our knowledge of Martian weather. And Mars is in spectacular view right now. It’s low in the east-southeast at nightfall, shining like a brilliant orange beacon. It scoots across the south during the night and is low in the west at dawn — if you can see it through the morning fog and clouds here on Earth.   Script by Damond Benningfield, Copyright 2014 For more skywatching tips, astronomy news, and much more, read StarDate magazine.      Related StoriesMars at Opposition II - EnclosureMorning FogRunaway Stars - Enclosure 

  • Earth will zip past the planet Mars tomorrow, leaving it behind as we follow our smaller, faster orbit around the Sun. As a result of that encounter, Mars is putting in its best showing of the year. It looks like a brilliant orange star, and for most of the night it’s the third-brightest object in the sky — only the Moon and Jupiter outshine it. This passage is known as opposition — Mars lines up opposite the Sun in our sky. It rises around sunset and remains in the sky all night. And it’ll be closest to us in a few days, at a distance of about 57 million miles. That makes the planet shine brighter than at any other time during its sojourn across the sky. This opposition is relatively puny, though. That’s because Mars’s orbit around the Sun is more lopsided than Earth’s is. This time around, we’re catching Mars when it’s relatively far from the Sun. At some other oppositions, Mars is much closer to the Sun, so it’s also closer to us, making it shine brighter. Even so, the Red Planet is putting in quite a showing. It’s low in the east-southeast as the sky gets good and dark, with the bright star Spica below it. Mars wheels low across the south during the night, and is in the west at first light. It’ll begin to fade in a few weeks, though, and by mid-May it will shine just half as bright as it does now. So take a look at the planet as it shines at its orangey best over the next couple of weeks. More about Mars tomorrow.   Script by Damond Benningfield, Copyright 2014 For more skywatching tips, astronomy news, and much more, read StarDate magazine.      Related StoriesNorth Galactic Pole - EnclosureNorth Galactic PoleMars at Opposition III - Enclosure 

  • Jupiter is the giant of the solar system. It’s more than 10 times wider than Earth, and has about 120 times the surface area. That’s a lot of territory to explore. So far, though, we’ve sampled just a tiny patch of it. A small probe parachuted through Jupiter’s thick atmosphere in 1995, and transmitted a few minutes of readings on the chemistry, wind speeds, and more. To learn more than that, we’ll need probes that can stay aloft for a while. One option is to attach instruments to a giant balloon and let it float along with the planet’s high-speed winds. And a decade ago, a small study done for NASA proposed a nuclear-powered ramjet. The craft would fly along at three times the speed of sound, scooping up hydrogen gas from Jupiter’s upper atmosphere. A small nuclear generator would heat the compressed gas, and an engine would shoot it out the back. Instruments would be housed in the craft’s wings, and small probes would be dropped every few thousand miles to sample lower altitudes. The study concluded that such a craft could circle Jupiter several times. Like many such plans, it’s not likely to be developed for quite a while — if ever. But it shows that there are options if we want to drop in on the solar system’s largest planet. And Jupiter is in good view tonight. It looks like a brilliant star. It’s to the upper right of the Moon at nightfall, and tags along with the Moon as they drop down the western sky later on.   Script by Damond Benningfield, Copyright 2014 For more skywatching tips, astronomy news, and much more, read StarDate magazine.      Related StoriesMoon and Jupiter - EnclosureStepping Stone - EnclosureNorth Galactic Pole - Enclosure 

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