This snapshot from the International Space Station was taken on August 11 while orbiting about 430 kilometers above the Indian Ocean, Southern Hemisphere, planet Earth. The spectacular view looks south and east, down toward the planet's horizon and through red and green curtains of aurora australis. The auroral glow is caused by emission from excited oxygen atoms in the extremely rarefied upper atmosphere still present at the level of the orbiting outpost. Green emission from atomic oxygen dominates this scene at altitudes of 100 to 250 kilometers, while red emission from atomic oxygen can extend as high as 500 kilometers altitude. Beyond the glow of these southern lights, this view from low Earth orbit reveals the starry sky from a southern hemisphere perspective. Stars in Orion's belt and the Orion Nebula are near the Earth's limb just left of center. Sirius, alpha star of Canis Major and brightest star in planet Earth's night is above center along the right edge of the southern orbital skyscape.

Looking Up: International Observe the Moon Night

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This spectacular mosaic of images from the James Webb Space Telescope peers into the heart of young star cluster NGC 1333. A mere 1,000 light-years distant toward the heroic constellation Perseus, the nearby star cluster lies at the edge of the large Perseus molecular cloud. Part of Webb's deep exploration of the region to identify low mass brown dwarf stars and free floating planets, the space telescope's combined field of view spans nearly 2 light-years across the dusty cluster's turbulent stellar nursery. In fact, NGC 1333 is known to harbor stars less than a million years old, though most are hidden from optical telescopes by the pervasive stardust. The chaotic environment may be similar to one in which our own Sun formed over 4.5 billion years ago.

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Mars has two tiny moons, Phobos and Deimos, named for the figures in Greek mythology Fear and Panic. Detailed surface views of smaller moon Deimos are shown in both these panels. The images were taken in 2009, by the HiRISE camera on board the Mars Reconnaissance Orbiter spacecraft, NASA's long-lived interplanetary internet satellite. The outermost of the two Martian moons, Deimos is one of the smallest known moons in the Solar System, measuring only about 15 kilometers across. Both Martian moons were discovered in 1877 by Asaph Hall, an American astronomer working at the US Naval Observatory in Washington D.C. But their existence was postulated around 1610 by Johannes Kepler, the astronomer who derived the laws of planetary motion. In this case, Kepler's prediction was not based on scientific principles, but his writings and ideas were so influential that the two Martian moons are discussed in works of fiction such as Jonathan Swift's Gulliver's Travels, written in 1726, over 150 years before their discovery.

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Galaxies of the NGC 7771 Group are featured in this intriguing skyscape. Some 200 million light-years distant toward the constellation Pegasus, NGC 7771 is the large, edge-on spiral near center, about 75,000 light-years across, with two smaller galaxies below it. Large spiral NGC 7769 is seen face-on to the right. Galaxies of the NGC 7771 group are interacting, making repeated close passages that will ultimately result in galaxy-galaxy mergers on a cosmic timescale. The interactions can be traced by distortions in the shape of the galaxies themselves and faint streams of stars created by their mutual gravitational tides. But a clear view of this galaxy group is difficult to come by as the deep image also reveals extensive clouds of foreground dust sweeping across the field of view. The dim, dusty galactic cirrus clouds are known as Integrated Flux Nebulae. The faint IFN reflect starlight from our own Milky Way Galaxy and lie only a few hundred light-years above the galactic plane.

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The full Moon and Earth's shadow set together in this island skyscape. The alluring scene was captured Tuesday morning, August 20, from Fiji, South Pacific Ocean, planet Earth. For early morning risers shadowset in the western sky is a daily apparition. Still, the grey-blue shadow is often overlooked in favor of a brighter eastern horizon. Extending through the dense atmosphere, Earth's setting shadow is bounded above by a pinkish glow or anti-twilight arch. Known as the Belt of Venus, the arch's lovely color is due to backscattering of reddened light from the opposite horizon's rising Sun. Of course, the setting Moon's light is reddened by the long sight-line through the atmosphere. But on that date the full Moon could be called a seasonal Blue Moon, the third full Moon in a season with four full Moons. And even though the full Moon is always impressive near the horizon, August's full Moon is considered by some the first of four consecutive full Supermoons in 2024.

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There is a quiet pulsar at the heart of CTA 1. The supernova remnant was discovered as a source of emission at radio wavelengths by astronomers in 1960 and since identified as the result of the death explosion of a massive star. But no radio pulses were detected from the expected pulsar, the rotating neutron star remnant of the massive star's collapsed core. Seen about 10,000 years after the initial supernova explosion, the interstellar debris cloud is faint at optical wavelengths. CTA 1's visible wavelength emission from still expanding shock fronts is revealed in this deep telescopic image, a frame that spans about 2 degrees across a starfield in the northern constellation of Cepheus. While no pulsar has since been found at radio wavelengths, in 2008 the Fermi Gamma-ray Space Telescope detected pulsed emission from CTA 1, identifying the supernova remnant's rotating neutron star. The source has been recognized as the first in a growing class of pulsars that are quiet at radio wavelengths but pulse in high-energy gamma-rays.

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On August 11 a Rocket Lab Electron rocket launched from a rotating planet. With a small satellite on board its mission was dubbed A Sky Full of SARs (Synthetic Aperture Radar satellites), departing for low Earth orbit from Mahia Peninsula on New Zealand's north island. The fiery trace of the Electron's graceful launch arc is toward the east in this southern sea and skyscape, a composite of 50 consecutive frames taken over 2.5 hours. Fixed to a tripod, the camera was pointing directly at the South Celestial Pole, the extension of planet Earth's axis of rotation in to space. But no bright star marks that location in the southern hemisphere's night sky. Still, the South Celestial Pole is easy to spot. It lies at the center of the concentric star trail arcs that fill the skyward field of view.

Gallery: Perseid Meteor Shower 2024 and Aurorae

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On August 11 a Rocket Lab Electron rocket launched from a rotating planet. With a small satellite on board its mission was dubbed A Sky Full of SARs (Synthetic Aperture Radar satellites), departing for low Earth orbit from Mahia Peninsula on New Zealand's north island. The fiery trace of the Electron's graceful launch arc is toward the east in this southern sea and skyscape, a composite of 50 consecutive frames taken over 2.5 hours. Fixed to a tripod, the camera was pointing directly at the South Celestial Pole, the extension of planet Earth's axis of rotation in to space. But no bright star marks that location in the southern hemisphere's night sky. Still, the South Celestial Pole is easy to spot. It lies at the center of the concentric star trail arcs that fill the skyward field of view.

Gallery: Perseid Meteor Shower 2024 and Aurorae

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A single exposure made with a camera pointed almost due north on August 12 recorded this bright Perseid meteor in the night sky west of Halifax, Nova Scotia, Canada. The meteor's incandescent trace is fleeting. It appears to cross the stars of the Big Dipper, famous northern asterism and celestial kitchen utensil, while shimmering curtains of aurora borealis, also known as the northern lights, dance in the night. Doubling the wow factor for night skywatchers near the peak of this year's Perseid meteor shower auroral activity on planet Earth was enhanced by geomagnetic storms. The intense space weather was triggered by flares from an active Sun.

Gallery: Perseid Meteor Shower 2024 and Aurorae

Source: apod.nasa.gov

Bright Mars and even brighter Jupiter are in close conjunction just above the pine trees in this post-midnight skyscape from Vallentuna, Sweden. Taken on August 12 during a geomagnetic storm, the snapshot records the glow of aurora borealis or northern lights, beaming from the left side of the frame. Of course on that date Perseid meteors rained through planet Earth's skies, grains of dust from the shower's parent, periodic comet Swift-Tuttle. The meteor streak at the upper right is a Perseid plowing through the atmosphere at about 60 kilometers per second. Also well-known in in Earth's night sky, the bright Pleides star cluster shines below the Perseid meteor streak. In Greek myth, the Pleiades were seven daughters of the astronomical titan Atlas and sea-nymph Pleione. The Pleiades and their parents' names are given to the cluster's nine brightest stars.

Gallery: Perseid Meteor Shower 2024 and Aurorae

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Messier 20, popularly known as the Trifid Nebula, lies about 5,000 light-years away toward the nebula rich constellation Sagittarius. A star forming region in the plane of our galaxy, the Trifid does illustrate three different types of astronomical nebulae; red emission nebulae dominated by light from hydrogen atoms, blue reflection nebulae produced by dust reflecting starlight, and dark nebulae where dense dust clouds appear in silhouette. The reddish emission region, roughly separated into three parts by obscuring dust lanes, is what lends the Trifid its popular name. The cosmic cloud complex is over 40 light-years across and would cover the area of a full moon on planet Earth's sky. But the Trifid Nebula is too faint to be seen by the unaided eye. Over 75 hours of image data captured under dark night skies was used to create this stunning telescopic view.

Watch: The Perseid Meteor Shower

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A Halley-type comet with an orbital period of about 133 years, Comet 109P/Swift-Tuttle is recognized as the parent of the annual Perseid Meteor Shower. The comet's last visit to the inner Solar System was in 1992. Then, it did not become easily visible to the naked eye, but it did become bright enough to see from most locations with binoculars and small telescopes. This stunning color image of Swift-Tuttle's greenish coma, long ion tail and dust tail was recorded using film on November 24, 1992. That was about 16 days after the large periodic comet's closest approach to Earth. Comet Swift-Tuttle is expected to next make an impressive appearance in night skies in 2126. Meanwhile, dusty cometary debris left along the orbit of Swift-Tuttle will continue to be swept up creating planet Earth's best-known July and August meteor shower.

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A Halley-type comet with an orbital period of about 133 years, Comet 109P/Swift-Tuttle is recognized as the parent of the annual Perseid Meteor Shower. The comet's last visit to the inner Solar System was in 1992. Then, it did not become easily visible to the naked eye, but it did become bright enough to see from most locations with binoculars and small telescopes. This stunning color image of Swift-Tuttle's greenish coma, long ion tail and dust tail was recorded using film on November 24, 1992. That was about 16 days after the large periodic comet's closest approach to Earth. Comet Swift-Tuttle is expected to next make an impressive appearance in night skies in 2126. Meanwhile, dusty cometary debris left along the orbit of Swift-Tuttle will continue to be swept up creating planet Earth's best-known July and August meteor shower.

Source: apod.nasa.gov

On a road trip up Mount Uludağ in Bursa province, Turkey these motorcyclists found themselves above low clouds and fog in late June. With the bright Sun directly behind them, the view down the side of the great mountain revealed a beautiful, atmospheric glory and fog bow. Known to some as the heiligenschein or the Specter of the Brocken, a glory can also sometimes be seen from airplanes or even high buildings. It often appears to be a dark giant surrounded by a bright halo. Of course the dark giant is just the shadow of the observer (90MB video) cast opposite the Sun. The clouds and fog are composed of very small water droplets, smaller than rain drops, that refract and reflect sunlight to create the glory's colorful halo and this more extensive fog bow.

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As Mars wanders through Earth's night, it passes about 5 degrees south of the Pleiades star cluster in this composite astrophoto. The skyview was constructed from a series of images captured over a run of 16 consecutive clear nights beginning on July 12. Mars' march across the field of view begins at the far right, the planet's ruddy hue. showing a nice contrast with the blue Pleiades stars. Moving much faster across the sky against the distant stars, the fourth planet from the Sun easily passes seventh planet Uranus, also moving across this field of view. Red planet Mars and the ice giant world were in close conjunction, about 1/2 degree apart, on July 16. Continuing its rapid eastward trek, Mars has now left the sister stars and outer planet behind though, passing north of red giant star Aldebaran. Mars will come within about 1/3 degree of Jupiter in planet Earth's sky on August 14.

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A visitor to the inner solar system every 70 years or so Comet 13P/Olbers reached its most recent perihelion, or closest approach to the Sun, on June 30 2024. Now on a return voyage to the distant Oort cloud the Halley-type comet is recorded here sweeping through northern summer night skies over historic Kunetice Castle, Czech Republic. Along with a broad dust tail, and brighter coma, this comet's long ion tail buffeted by storms and winds from the Sun, is revealed in the composite of tracked exposures for comet and sky, and fixed exposures for foreground landscape recorded on July 28. The comet is about 16 light-minutes beyond the castle and seen against faint background stars below the northern constellation Ursa Major. The hilltop castle dates to the 15th century, while Heinrich Olbers discovered the comet in 1815. Captured here low in northwestern skies just after sunset Comet Olbers, for now, offers skywatchers on planet Earth rewarding telescopic and binocular views. Comet 13P/Olbers next perihelion passage will be in 2094.

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Saturn now rises before midnight in planet Earth's sky. On July 24, the naked-eye planet was in close conjunction, close on the sky, to a waning gibbous Moon. But from some locations on planet Earth the ringed gas giant was occulted, disappearing behind the Moon for about an hour from skies over parts of Asia and Africa. Because the Moon and bright planets wander through the sky near the ecliptic plane, such occultation events are not uncommon, but they can be dramatic. In this telescopic view from Nanjing, Jiangsu, China, Saturn is caught moments before its disappearance behind the lunar disk. The snapshot gives the illusion that Saturn hangs just above Glushko crater, a 43 kilometer diameter, young, ray crater near the Moon's western edge. Of course, the Moon is 400 thousand kilometers away, compared to Saturn's distance of 1.4 billion kilometers.

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For some, these subtle bands of light and shadow stretched across the sky as the Sun set on July 11. Known as anticrepuscular rays, the bands are formed as a large cloud bank near the western horizon cast long shadows through the atmosphere at sunset. Due to the camera's perspective, the bands of light and shadow seem to converge toward the eastern (opposite) horizon at a point seen just above a 14th century hilltop castle near Brno, Czech Republic. In the foreground, denizens of planet Earth are enjoying the region's annual Planet Festival in the park below the Brno Observatory and Planetarium. And while crepuscular and anticrepuscular rays are a relatively common atmospheric phenomenon, this festival's 10 meter diameter inflatable spheres representing bodies of the Solar System are less often seen on planet Earth.

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Globular star cluster Omega Centauri packs about 10 million stars much older than the Sun into a volume some 150 light-years in diameter. Also known as NGC 5139, at a distance of 15,000 light-years it's the largest and brightest of 200 or so known globular clusters that roam the halo of our Milky Way galaxy. Though most star clusters consist of stars with the same age and composition, the enigmatic Omega Cen exhibits the presence of different stellar populations with a spread of ages and chemical abundances. In fact, Omega Cen may be the remnant core of a small galaxy merging with the Milky Way. With a yellowish hue, Omega Centauri's red giant stars are easy to pick out in this sharp telescopic view. A two-decade-long exploration of the dense star cluster with the Hubble Space Telescope has revealed evidence for a massive black hole near the center of Omega Centauri.

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Found among the rich starfields of the Milky Way, star cluster NGC 7789 lies about 8,000 light-years away toward the constellation Cassiopeia. A late 18th century deep sky discovery of astronomer Caroline Lucretia Herschel, the cluster is also known as Caroline's Rose. Its visual appearance in small telescopes, created by the cluster's complex of stars and voids, is suggestive of nested rose petals. Now estimated to be 1.6 billion years young, the galactic or open cluster of stars also shows its age. All the stars in the cluster were likely born at the same time, but the brighter and more massive ones have more rapidly exhausted the hydrogen fuel in their cores. These have evolved from main sequence stars like the Sun into the many red giant stars shown with a yellowish cast in this color composite. Using measured color and brightness, astronomers can model the mass and hence the age of the cluster stars just starting to "turn off" the main sequence and become red giants. Over 50 light-years across, Caroline's Rose spans about half a degree (the angular size of the Moon) near the center of the sharp telescopic image.

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A glow from the summit of Mount Etna, famous active stratovolcano of planet Earth, stands out along the horizon in this mountain and night skyscape. Bands of diffuse light from congeries of innumerable stars along the Milky Way galaxy stretch across the sky above. In silhouette, the Milky Way's massive dust clouds are clumped along the galactic plane. But also familiar to northern skygazers are bright stars Deneb, Vega, and Altair, the Summer Triangle straddling dark nebulae and luminous star clouds poised over the volcanic peak. The deep combined exposures also reveal the light of active star forming regions along the Milky Way, echoing Etna's ruddy hue in the northern hemisphere summer's night.

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