Astronomy Picture of the Day

🌌NGC 247 and Friends About 70,000 light-years across, NGC 247 is a spiral galaxy smaller than our Milky Way. Measured to be only 11 million light-years distant it is nearby though. Tilted nearly edge-on as seen from our perspective, it dominates this telescopic field of view toward the southern constellation Cetus. The pronounced void on one side of the galaxy's disk recalls for some its popular ...

© Mike Taivalmaa

🌌NGC 6995: The Bat Nebula Can you see the bat? It haunts this cosmic close-up of the eastern Veil Nebula. The Veil Nebula itself is a large supernova remnant, the expanding debris cloud from the death explosion of a massive star. While the Veil is roughly circular in shape and covers nearly 3 degrees on the sky toward the constellation of the Swan (Cygnus), NGC 6995, known informally as the Bat ...

© Alan Dyer, TWAN

🌌Quarter Moon and Sister Stars Nine days ago, two quite different sky icons were imaged rising together. Specifically, Earth's Moon shared the eastern sky with the sister stars of the Pleiades cluster, as viewed from Alberta, Canada. Astronomical images of the well-known Pleiades often show the star cluster's alluring blue reflection nebulas, but here they are washed-out by the orange moonrise s ...

© Andrea Vanoni

🌌A Triangular Prominence Hovers Over the Sun Why is there a triangle hovering over the Sun? Although the shape is unusual, the type of structure is not: it is part of an evolving solar prominence. Looping magnetic fields on the Sun channel the flow of energetic particles, sometimes holding glowing gaseous structures aloft for months. A prominence glows brightly because it contains particularly h ...

© Francisco Sojuel

🌌The Moon Dressed Like Saturn Why does Saturn appear so big? It doesn't -- what is pictured are foreground clouds on Earth crossing in front of the Moon. The Moon shows a slight crescent phase with most of its surface visible by reflected Earthlight, known as Da Vinci glow. The Sun directly illuminates the brightly lit lunar crescent from the bottom, which means that the Sun must be below the ho ...

© Steve Mandel

🌌IFN and the NGC 7771 Group 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 ...

© Lorand Fenyes

🌌Southern Moonscape The Moon's south pole is toward the top left of this detailed telescopic moonscape. Captured on August 23, it looks across the rugged southern lunar highlands. The view's foreshortened perspective heightens the impression of a dense field of craters and makes the craters themselves appear more oval shaped close to the lunar limb. Prominent near center is 114 kilometer diamete ...

© Gaetan Maxant

🌌Star Factory Messier 17 A nearby star factory known as Messier 17 lies some 5,500 light-years away in the nebula-rich constellation Sagittarius. At that distance, this 1.5 degree wide field-of-view would span about 150 light-years. In the sharp color composite image faint details of the region's gas and dust clouds are highlighted with narrowband image data against a backdrop of central Milky W ...

© Anirudh Shastry

🌌Tulip Nebula and Black Hole Cygnus X-1 When can you see a black hole, a tulip, and a swan all at once? At night -- if the timing is right, and if your telescope is pointed in the right direction. The complex and beautiful Tulip Nebula blossoms about 8,000 light-years away toward the constellation of Cygnus the Swan. Ultraviolet radiation from young energetic stars at the edge of the Cygnus OB3 ...

© Pau Montplet Sanz

🌌Moon Eclipses Saturn What if Saturn disappeared? Sometimes, it does. It doesn't really go away, though, it just disappears from view when our Moon moves in front. Such a Saturnian eclipse, more formally called an occultation, was visible along a long swath of Earth -- from Peru, across the Atlantic Ocean, to Italy -- only a few days ago. The featured color image is a digital fusion of the clear ...

🌌Perseid Meteors Over Inner Mongolia Did you see it? One of the more common questions during a meteor shower occurs because the time it takes for a meteor to flash is similar to the time it takes for a head to turn. Possibly, though, the glory of seeing bright meteors shoot across the sky -- while knowing that they were once small pebbles on another world -- might make it all worthwhile, even if ...

🌌Fresh Tiger Stripes on Saturn's Enceladus Do underground oceans vent through canyons on Saturn's moon Enceladus? Long features dubbed tiger stripes are known to be spewing ice from the moon's icy interior into space, creating a cloud of fine ice particles over the moon's South Pole and creating Saturn's mysterious E-ring. Evidence for this has come from the robot Cassini spacecraft that orbited ...

© full Moon

🌌South Pacific Shadowset 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 atm ...

© Thomas Lelu

🌌Supernova Remnant CTA 1 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 1 ...

© Mike Selby

🌌The Dark Tower in Scorpius In silhouette against a crowded star field along the tail of the arachnological constellation Scorpius, this dusty cosmic cloud evokes for some the image of an ominous dark tower. In fact, monstrous clumps of dust and molecular gas collapsing to form stars may well lurk within the dark nebula, a structure that spans almost 40 light-years across this gorgeous telescopi ...

🌌Fermi's 12-year All-Sky Gamma-ray Map Forget X-ray vision — imagine what you could see with gamma-ray vision! The featured all-sky map shows what the universe looks like to NASA's Fermi Gamma-ray Space Telescope. Fermi sees light with energies about a billion times what the human eye can see, and the map combines 12 years of Fermi observations. The colors represent the brightness of the gamma-r ...

🌌Supermoon Beyond the Temple of Poseidon A supermoon occurred yesterday. And tonight's moon should also look impressive. Supermoons appear slightly larger and brighter than most full moons because they reach their full phase when slightly nearer to the Earth -- closer than 90 percent of all full moons. This supermoon was also a blue moon given the definition that it is the third of four full moo ...

© Luis Romero Ventura

🌌IC 5146: The Cocoon Nebula Inside the Cocoon Nebula is a newly developing cluster of stars. Cataloged as IC 5146, the beautiful nebula is nearly 15 light-years wide. Soaring high in northern summer night skies, it's located some 4,000 light years away toward the constellation of the Swan (Cygnus). Like other star forming regions, it stands out in red, glowing, hydrogen gas excited by young, hot ...

🌌A Solar Prominence Eruption from SDO One of the most spectacular solar sights is an erupting prominence. In 2011, NASA's Sun-orbiting Solar Dynamic Observatory spacecraft imaged an impressively large prominence erupting from the surface. The dramatic explosion was captured in ultraviolet light in the featured time lapse video covering 90 minutes, where a new frame was taken every 24 seconds. Th ...

© Rory Gannaway

🌌Sky Full of Arcs 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 ...

© Jason Dain

🌌Meteor Borealis 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 n ...

© Clear Skies

🌌Late Night Vallentuna 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 skie ...

© Chantal Anders

🌌Meteors and Aurora over Germany This was an unusual night. For one thing, the night sky of August 11 and 12, earlier this week, occurred near the peak of the annual Perseid Meteor Shower. Therefore, meteors streaked across the dark night as small bits cast off from Comet Swift-Tuttle came crashing into the Earth's atmosphere. Even more unusually, for central Germany at least, the night sky glow ...

🌌Giant Jet from the International Space Station What's that on the horizon? When circling the Earth on the International Space Station early last month, astronaut Matthew Dominick saw an unusual type of lightning just beyond the Earth's edge: a gigantic jet. The powerful jet appears on the left of the featured image in red and blue. Giant jet lightning has only been known about for the past 23 y ...

© Josh Dury

🌌Perseid Meteors over Stonehenge What's happening in the sky above Stonehenge? A meteor shower: specifically, the Perseid meteor shower. A few nights ago, after the sky darkened, many images of meteors from this year's Perseids were captured separately and merged into a single frame. Although the meteors all traveled on straight paths, these paths appear slightly curved by the wide-angle lens of ...

🌌Animation: Perseid Meteor Shower Where do Perseid meteors come from? Mostly small bits of stony grit, Perseid meteoroids were once expelled from Comet Swift-Tuttle and continue to follow this comet's orbit as they slowly disperse. The featured animation depicts the entire meteoroid stream as it orbits our Sun. When the Earth nears this stream, as it does every year, the Perseid Meteor Shower oc ...

© Robert Edelmaier and Gabriele Gegenbauer

🌌The Light, Dark, and Dusty Trifid 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 ref ...