The Ghostly Veil Nebula The Ghostly Veil Nebula

A ghostly visage on a cosmic scale, these remains of shocked, glowing gas haunt planet Earth's sky toward the constellation of Cygnus and form the Veil Nebula. The nebula itself is a large supernova remnant, an expanding cloud born of the death explosion of a massive star. Light from the original supernova explosion likely reached Earth over 5,000 years ago. Also known as the Cygnus Loop, the Veil Nebula now spans nearly 3 degrees or about 6 times the diameter of the full Moon. That translates to over 70 light-years at its estimated distance of 1,500 light-years. In fact, the Veil is so large its brighter parts are recognized as separate nebulae, including The Witch's Broom (NGC 6960) below and right of center. At the top left you can find the Spectre of IC 1340. Happy Halloween! via NASA https://ift.tt/2N29YAQ

M42: Inside the Orion Nebula M42: Inside the Orion Nebula

The Great Nebula in Orion, an immense, nearby starbirth region, is probably the most famous of all astronomical nebulas. Here, glowing gas surrounds hot young stars at the edge of an immense interstellar molecular cloud only 1500 light-years away. In the featured deep image in assigned colors highlighted by emission in oxygen and hydrogen, wisps and sheets of dust and gas are particularly evident. The Great Nebula in Orion can be found with the unaided eye near the easily identifiable belt of three stars in the popular constellation Orion. In addition to housing a bright open cluster of stars known as the Trapezium, the Orion Nebula contains many stellar nurseries. These nurseries contain much hydrogen gas, hot young stars, proplyds, and stellar jets spewing material at high speeds. Also known as M42, the Orion Nebula spans about 40 light years and is located in the same spiral arm of our Galaxy as the Sun. via NASA https://ift.tt/2NjuSu4

Curiosity Rover Finds a Clay Cache on Mars Curiosity Rover Finds a Clay Cache on Mars

Why is there clay on Mars? On Earth, clay can form at the bottom of a peaceful lake when specific minerals trap water. At the pictured site on Mars, the robotic rover Curiosity drilled into two rocks and found the highest concentration of clay yet. The clay cache is considered addition evidence that Gale Crater once held water in the distant past. Pictured, 57 images taken by Curiosity have been combined into a selfie. The images were taken by a camera at the end of its robotic arm. Many details of the car-sized rover are visible, including its rugged wheels, numerous scientific instruments, and a high mast that contains camera "eyes", one of which can shoot out an infrared laser beam. Curiosity continues to roll around and up Mount Sharp -- in the center of Gale Crater -- in a search for new clues about the ancient history of Mars and whether or not the red planet once had conditions that could support life. via NASA https://ift.tt/2WnzOSX

The Space Station Crosses a Spotless Sun The Space Station Crosses a Spotless Sun

Typically, the International Space Station is visible only at night. Slowly drifting across the night sky as it orbits the Earth, the International Space Station (ISS) can be seen as a bright spot about once a month from many locations. The ISS is then visible only just after sunset or just before sunrise because it shines by reflected sunlight -- once the ISS enters the Earth's shadow, it will drop out of sight. The only occasion when the ISS is visible during the day is when it passes right in front of the Sun. Then, it passes so quickly that only cameras taking short exposures can visually freeze the ISS's silhouette onto the background Sun. The featured picture did exactly that -- it is actually a series of images taken a month ago from Santa Fe, Argentina with perfect timing. This image series was later combined with a separate image highlighting the texture of the spotless Sun, and an image bringing up the Sun's prominences around the edge. At an unusually low Solar Minimum, the Sun has gone without sunspots now for most of 2019. via NASA https://ift.tt/2NhTbsh

Ghost Aurora over Canada Ghost Aurora over Canada

What does this aurora look like to you? While braving the cold to watch the skies above northern Canada early one morning in 2013, a most unusual aurora appeared. The aurora definitely appeared to be shaped like something , but what? Two ghostly possibilities recorded by the astrophotographer were "witch" and "goddess of dawn", but please feel free to suggest your own Halloween-enhanced impressions. Regardless of fantastical pareidolic interpretations, the pictured aurora had a typical green color and was surely caused by the scientifically commonplace action of high energy particles from space interacting with oxygen in Earth's upper atmosphere. In the image foreground, at the bottom, is a frozen Alexandra Falls, while evergreen trees cross the middle. via NASA https://ift.tt/2Njd9CP

Gravity s Grin Gravity s Grin

Albert Einstein's general theory of relativity, published over 100 years ago, predicted the phenomenon of gravitational lensing. And that's what gives these distant galaxies such a whimsical appearance, seen through the looking glass of X-ray and optical image data from the Chandra and Hubble space telescopes. Nicknamed the Cheshire Cat galaxy group, the group's two large elliptical galaxies are suggestively framed by arcs. The arcs are optical images of distant background galaxies lensed by the foreground group's total distribution of gravitational mass. Of course, that gravitational mass is dominated by dark matter. The two large elliptical "eye" galaxies represent the brightest members of their own galaxy groups which are merging. Their relative collisional speed of nearly 1,350 kilometers/second heats gas to millions of degrees producing the X-ray glow shown in purple hues. Curiouser about galaxy group mergers? The Cheshire Cat group grins in the constellation Ursa Major, some 4.6 billion light-years away. via NASA https://ift.tt/2PkdyaR

The Ghosts of Cassiopeia The Ghosts of Cassiopeia

These bright rims and flowing shapes look ghostly on a cosmic scale. A telescopic view toward the constellation Cassiopeia, the colorful skyscape features swept-back, comet-shaped clouds IC 59 (left) and IC 63. About 600 light-years distant, the clouds aren't actually ghosts. They are slowly disappearing though, under the influence of energetic radiation from hot,luminous star gamma Cas. Gamma Cas is physically located only 3 to 4 light-years from the nebulae, the bright star just above and left in the frame. Slightly closer to gamma Cas, IC 63 is dominated by red H-alpha light emitted as hydrogen atoms ionized by the star's ultraviolet radiation recombine with electrons. Farther from the star, IC 59 shows proportionally less H-alpha emission but more of the characteristic blue tint of dust reflected star light. The field of view spans over 1 degree or 10 light-years at the estimated distance of gamma Cas and friends. via NASA https://ift.tt/2BEIpHa

Starry Night by Vincent van Gogh Starry Night by Vincent van Gogh

The painting Starry Night is one of the most famous icons of the night sky ever created. The scene was painted by Vincent van Gogh in southern France in 1889. The swirling style of Starry Night appears, to many, to make the night sky come alive. Although van Gogh frequently portrayed real settings in his paintings, art historians do not agree on precisely what stars and planets are being depicted in Starry Night. The style of Starry Night is post-impressionism, a popular painting style at the end of the nineteenth century. The original Starry Night painting hangs in the Museum of Modern Art in New York City, New York, USA. via NASA https://ift.tt/2o9Xv4p

Night Sky Reflections from the Worlds Largest Mirror Night Sky Reflections from the Worlds Largest Mirror

What's being reflected in the world's largest mirror? Stars, galaxies, and a planet. Many of these stars are confined to the grand arch that runs across the image, an arch that is the central plane of our home Milky Way Galaxy. Inside the arch is another galaxy -- the neighboring Large Magellanic Cloud (LMC). Stars that are individually visible include Antares on the far left and Sirius on the far right. The planet Jupiter shines brightly just below Antares. The featured picture is composed of 15 vertical frames taken consecutively over ten minutes from the Uyuni Salt Flat in Bolivia. Uyuni Salt Flat (Salar de Uyuni) is the largest salt flat on Earth and is so large and so extraordinarily flat that, after a rain, it can become the world's largest mirror -- spanning 130 kilometers. This expansive mirror was captured in early April reflecting each of the galaxies, stars, and planet mentioned above. via NASA https://ift.tt/2oTd3Ki

A Mercury Transit Music Video from SDO A Mercury Transit Music Video from SDO

What's that small black dot moving across the Sun? Mercury. Possibly the clearest view of Mercury crossing in front of the Sun in 2016 May was from Earth orbit. The Solar Dynamics Observatory obtained an uninterrupted vista recording it not only in optical light but also in bands of ultraviolet light. Featured here is a composite movie of the crossing set to music. Although the event might prove successful scientifically for better determining components of Mercury' ultra-thin atmosphere, the event surely proved successful culturally by involving people throughout the world in observing a rare astronomical phenomenon. Many spectacular images of this Mercury transit from around (and above) the globe were proudly displayed. The next transit of Mercury will take place in three weeks: on 2019 November 11. via NASA https://ift.tt/2Pbfq5A

Pluto at Night Pluto at Night

The night side of Pluto spans this shadowy scene, a stunning spacebased view with the Sun 4.9 billion kilometers (almost 4.5 light-hours) behind the dim and distant world. It was captured by far flung New Horizons in July of 2015. The spacecraft was at a range of some 21,000 kilometers from Pluto, about 19 minutes after its closest approach. A denizen of the Kuiper Belt in dramatic silhouette, the image also reveals Pluto's tenuous, surprisingly complex layers of hazy atmosphere. The crescent twilight landscape near the top of the frame includes southern areas of nitrogen ice plains now formally known as Sputnik Planitia and rugged mountains of water-ice in the Norgay Montes. via NASA https://ift.tt/2MxB9TL

All Female Spacewalk Repairs Space Station All Female Spacewalk Repairs Space Station

The failed unit was beyond the reach of the robotic Canadarm2. Therefore, this repair of the International Space Station would require humans. The humans on duty were NASA's Jessica Meir and Christina Koch. This was the fourth spacewalk for Meir, the first for Koch, and the first all-female spacewalk in human history. The first woman to walk in space was Svetlana Savitskaya in 1984. Koch (red stripe) and Weir are pictured hard at work on the P6 Truss, with solar panels and the darkness of space in the background. Working over seven hours, the newly installed Battery Charge / Discharge Unit (BCDU) was successfully replaced and, when powered up, operated normally. via NASA https://ift.tt/2MUQWLq

Interstellar Interloper 2I Borisov Interstellar Interloper 2I Borisov

After the 2017 detecton of 1I/'Oumuamua, comet 2I/Borisov has become the second recognized interstellar interloper. Like 'Oumuamua, Borisov's measured hyperbolic trajectory and speed as it falls toward the Sun confirm that its origin is from beyond our Solar System. But while detailed observations indicate 'Oumuamua is a rocky body with differences from known Solar System objects, Borisov is definitely a far wandering comet. Taken on October 12, 2019 this Hubble Space Telescope image of Borisov reveals a familiar looking comet-like activity and concentration of dust around around its nucleus. Not resolved in the image, some estimates suggest the nucleus could be between 2 and 16 kilometers in diameter. At the time of the Hubble image, comet 2I/Borisov was about 418 million kilometers away. Borisov is still inbound though and will make its closest approach to the Sun on December 7 at a distance of about 300 million kilometers (2 Astronomical units). via NASA https://ift.tt/2o0KwC4

Moons of Saturn Moons of Saturn

On July 29, 2011 the Cassini spacecraft's narrow-angle camera took this snapshot and captured 5 of Saturn's moons, from just above the ringplane. Left to right are small moons Janus and Pandora respectively 179 and 81 kilometers across, shiny 504 kilometer diameter Enceladus, and Mimas, 396 kilometers across, seen just next to Rhea. Cut off by the right edge of the frame, Rhea is Saturn's second largest moon at 1,528 kilometers across. So how many moons does Saturn have? Twenty new found outer satellites bring its total to 82 known moons, and since Jupiter's moon total stands at 79, Saturn is the Solar System's new moon king. The newly announced Saturnian satellites are all very small, 5 kilometers or so in diameter, and most are in retrograde orbits inclined to Saturn's ringplane. You can help name Saturn's new moons, but you should understand the rules. Hint: A knowledge of Norse, Inuit, and Gallic mythology will help. via NASA https://ift.tt/2VMucBc

The Galaxy Above The Galaxy Above

Have you contemplated your home galaxy lately? If your sky looked like this, perhaps you'd contemplate it more often! The featured picture is actually a composite of two images taken last month from the same location in south Brazil and with the same camera -- but a few hours apart. The person in the image -- also the astrophotographer -- has much to see in the Milky Way Galaxy above. The central band of our home Galaxy stretches diagonally up from the lower left. This band is dotted with spectacular sights including dark nebular filaments, bright blue stars, and red nebulas. Millions of fainter and redder stars fill in the deep Galactic background. To the lower right of the Milky Way are the colorful gas and dust clouds of Rho Ophiuchus, featuring the bright orange star Antares. On this night, just above and to the right of Antares was a bright planet Jupiter. The sky is so old and so familiar that humanity has formulated many stories about it, some of which inspired this very picture. via NASA https://ift.tt/2oHA82j

Andromeda before Photoshop Andromeda before Photoshop

What does the Andromeda galaxy really look like? The featured image shows how our Milky Way Galaxy's closest major galactic neighbor really appears in a long exposure through Earth's busy skies and with a digital camera that introduces normal imperfections. The picture is a stack of 223 images, each a 300 second exposure, taken from a garden observatory in Portugal over the past year. Obvious image deficiencies include bright parallel airplane trails, long and continuous satellite trails, short cosmic ray streaks, and bad pixels. These imperfections were actually not removed with Photoshop specifically, but rather greatly reduced with a series of computer software packages that included Astro Pixel Processor, DeepSkyStacker, and PixInsight. All of this work was done not to deceive you with a digital fantasy that has little to do with the real likeness of the Andromeda galaxy (M31), but to minimize Earthly artifacts that have nothing to do with the distant galaxy and so better recreate what M31 really does look like. via NASA https://ift.tt/33xOKAd

A Stellar Jewel Box: Open Cluster NGC 290 A Stellar Jewel Box: Open Cluster NGC 290

Jewels don't shine this bright -- only stars do. Like gems in a jewel box, though, the stars of open cluster NGC 290 glitter in a beautiful display of brightness and color. The photogenic cluster, pictured here, was captured in 2006 by the orbiting Hubble Space Telescope. Open clusters of stars are younger, contain few stars, and contain a much higher fraction of blue stars than do globular clusters of stars. NGC 290 lies about 200,000 light-years distant in a neighboring galaxy called the Small Cloud of Magellan (SMC). The open cluster contains hundreds of stars and spans about 65 light years across. NGC 290 and other open clusters are good laboratories for studying how stars of different masses evolve, since all the open cluster's stars were born at about the same time. via NASA https://ift.tt/2Mej0dD

Interplanetary Earth Interplanetary Earth

In an interplanetary first, on July 19, 2013 Earth was photographed on the same day from two other worlds of the Solar System, innermost planet Mercury and ringed gas giant Saturn. Pictured on the left, Earth is the pale blue dot just below the rings of Saturn, as captured by the robotic Cassini spacecraft then orbiting the outermost gas giant. On that same day people across planet Earth snapped many of their own of their own pictures of Saturn. On the right, the Earth-Moon system is seen against the dark background of space as captured by the robotic MESSENGER spacecraft, then in Mercury orbit. MESSENGER took its image as part of a search for small natural satellites of Mercury, moons that would be expected to be quite dim. In the MESSENGER image, the Earth (left) and Moon (right) are overexposed and shine brightly with reflected sunlight. Destined not to return to their home world, both Cassini and Messenger have since retired from their missions of Solar System exploration. via NASA https://ift.tt/2q73ckd

Planet Earth at Blue Hour Planet Earth at Blue Hour

Nature photographers and other fans of planet Earth always look forward to the blue hour. That's the transition in twilight, just before sunrise or after sunset, when the Sun is below the horizon but land and sky are still suffused with beautiful bluish hues of light. On August 8 this early morning blue hour panorama scanned along the clear western sky, away from the impending sunrise. A breathtaking scene, it looks down the slopes of Mt. Whitney, from along the John Muir Trail toward rugged peaks of planet Earth's Sierra Nevada mountain range. Above the horizon a faint pinkish band of back scattered sunlight, the anti-twilight arch or Belt of Venus, borders the falling grey shadow of Earth itself. Subtle bands of light across the clear sky are anti-crepuscular rays, defined by shadows of clouds near the sunward horizon. Actually following parallel lines they seem to converge along the horizon at the point opposite the rising Sun due to perspective. via NASA https://ift.tt/2M4Jgqt

Mid Air Meteor and Milky Way Mid Air Meteor and Milky Way

On September 24, a late evening commercial flight from Singapore to Australia offered stratospheric views of the southern hemisphere's night sky, if you chose a window seat. In fact, a well-planned seating choice with a window facing toward the Milky Way allowed the set up of a sensitive digital camera on a tripod mount to record the galaxy's central bulge in a series of 10 second long exposures. By chance, one of the exposures caught this bright fireball meteor in the starry frame. Reflected along the wing of the A380 aircraft, the brilliant greenish streak is also internally reflected in the double layer window, producing a fainter parallel to the original meteor track. In the southern sky Jupiter is the bright source beneath the galactic bulge and seen next to a green beacon, just off the wing tip. via NASA https://ift.tt/2MqQsMU

NGC 7714: Starburst after Galaxy Collision NGC 7714: Starburst after Galaxy Collision

Is this galaxy jumping through a giant ring of stars? Probably not. Although the precise dynamics behind the featured image is yet unclear, what is clear is that the pictured galaxy, NGC 7714, has been stretched and distorted by a recent collision with a neighboring galaxy. This smaller neighbor, NGC 7715, situated off to the left of the featured frame, is thought to have charged right through NGC 7714. Observations indicate that the golden ring pictured is composed of millions of older Sun-like stars that are likely co-moving with the interior bluer stars. In contrast, the bright center of NGC 7714 appears to be undergoing a burst of new star formation. The featured image was captured by the Hubble Space Telescope. NGC 7714 is located about 130 million light years away toward the constellation of the Two Fish (Pisces). The interactions between these galaxies likely started about 150 million years ago and should continue for several hundred million years more, after which a single central galaxy may result. via NASA https://ift.tt/2LXq8uK

Sprite Lightning in HD Sprite Lightning in HD

This phenomenon occurs in the sky over our heads, not the sea. It is a type of lightning known as red sprite, and rarely has it ever been photographed in this detail. Even though sprites have been recorded for over 30 years, their root cause remains unknown. Some thunderstorms have them, but most don't. These mysterious bursts of light in the upper atmosphere momentarily resemble gigantic jellyfish. A few years ago high speed videos were taken detailing how red sprites actually develop. The featured image was captured last month in high definition from Italy. One unusual feature of sprites is that they are relatively cold -- they operate more like long fluorescent light tubes than hot compact light bulbs. In general, red sprites take only a fraction of a second to occur and are best seen when powerful thunderstorms are visible from the side. via NASA https://ift.tt/2obzIRH

Io Eclipse Shadow on Jupiter from Juno Io Eclipse Shadow on Jupiter from Juno

What's that dark spot on Jupiter? It's the shadow of Jupiter's most volcanic moon Io. Since Jupiter shines predominantly by reflected sunlight, anything that blocks that light leaves a shadow. If you could somehow be in that shadow, you would see a total eclipse of the Sun by Io. Io's shadow is about 3600 kilometers across, roughly the same size as Io itself -- and only slightly larger than Earth's Moon. The featured image was taken last month by NASA's robotic Juno spacecraft currently orbiting Jupiter. About every two months, Juno swoops close by Jupiter, takes a lot of data and snaps a series of images -- some of which are made into a video. Among many other things, Juno has been measuring Jupiter's gravitational field, finding surprising evidence that Jupiter may be mostly a liquid. Under unexpectedly thick clouds, the Jovian giant may house a massive liquid hydrogen region that extends all the way to the center. via NASA https://ift.tt/31VIYYw

The Horsehead Nebula The Horsehead Nebula

The Horsehead Nebula is one of the most famous nebulae on the sky. It is visible as the dark indentation to the red emission nebula in the center of the above photograph. The horse-head feature is dark because it is really an opaque dust cloud that lies in front of the bright red emission nebula. Like clouds in Earth's atmosphere, this cosmic cloud has assumed a recognizable shape by chance. After many thousands of years, the internal motions of the cloud will surely alter its appearance. The emission nebula's red color is caused by electrons recombining with protons to form hydrogen atoms. On the image left is the Flame Nebula, an orange-tinged nebula that also contains filaments of dark dust. Just to the lower left of the Horsehead nebula featured picture is a blueish reflection nebulae that preferentially reflects the blue light from nearby stars. via NASA https://ift.tt/2AKR8av

Jupiter and the Moons Jupiter and the Moons

After sunset on October 3, some of the Solar System's largest moons stood low along the western horizon with the largest planet. Just after nightfall, a pairing of the Moon approaching first quarter phase and Jupiter was captured in this telephoto field of view. A blend of short and long exposures, it reveals the familiar face of our fair planet's own large natural satellite in stark sunlight and faint earthshine. At lower right are the ruling gas giant and its four Galilean moons. Left to right, the tiny pinpricks of light are Ganymede, [Jupiter], Io, Europa, and Callisto. Our own natural satellite appears to loom large because it's close, but Ganymede, Io, and Callisto are actually larger than Earth's Moon. Water world Europa is only slightly smaller. Of the Solar System's six largest planetary satellites, only Saturn's moon Titan, is missing from this scene. But be sure to check for large moons in your sky tonight. via NASA https://ift.tt/31QTY9y

InSight on a Cloudy Day InSight on a Cloudy Day

Clouds drift through the sky as the light fades near sunset in this three frame animated gif. The scene was captured on sol 145 beginning around 6:30pm local time by a camera on the Mars InSight lander. Of course, InSight's martian day, sol 145, corresponds to Earth calendar date April 25, 2019. Under the 69 centimeter (2.3 foot) diameter dome in the foreground is the lander's sensitive seismometer SEIS designed to detect marsquakes. Earthquakes reveal internal structures on planet Earth, and so tremors detected by SEIS can explore beneath the martian surface. In particular, two typical marsquakes were recorded by SEIS on May 22 (sol 173) and July 25 (sol 235). The subtle tremors from the Red Planet are at very low frequencies though, and for listening have to be processed into the audio frequency range. In the sped up recordings external noises more prevalent on cool martian evenings and likely caused by mechanical shifts and contractions have been technically dubbed dinks and donks. via NASA https://ift.tt/30GdVid

The Hydrogen Clouds of M33 The Hydrogen Clouds of M33

Gorgeous spiral galaxy M33 seems to have more than its fair share of glowing hydrogen gas. A prominent member of the local group of galaxies, M33 is also known as the Triangulum Galaxy and lies a mere 3 million light-years away. The galaxy's inner 30,000 light-years or so are shown in this magnificent 25 panel telescopic mosaic. Based on image data from space and ground-based telescopes, the portrait of M33 shows off the galaxy's reddish ionized hydrogen clouds or HII regions. Sprawling along loose spiral arms that wind toward the core, M33's giant HII regions are some of the largest known stellar nurseries, sites of the formation of short-lived but very massive stars. Intense ultraviolet radiation from the luminous, massive stars ionizes the surrounding hydrogen gas and ultimately produces the characteristic red glow. To enhance this image, broadband data was used to produce a color view of the galaxy and combined with narrowband data recorded through a hydrogen-alpha filter. That filter transmits the light of the strongest visible hydrogen emission line. via NASA https://ift.tt/2oDShxK

Black Hole Safety Video Black Hole Safety Video

If you were a small one-eyed monster, would you want to visit a black hole? Well the one in this video does -- but should it? No, actually, but since our little friend is insistent on going, the video informs it what black holes really are, and how to be as safe as possible when visiting. Black holes are clumps of matter so dense that light cannot escape. Pairs of black holes, each several times the mass of our Sun, have recently been found to merge by detection of unusual gravitational radiation. The regions surrounding supermassive black holes in the centers of galaxies can light up as stars that near them get shredded. The closest known black hole to the Earth is V616 Mon, which is about 3,300 light years away. The best way for our monster friend to stay safe, the video informs, is to not go too close. via NASA https://ift.tt/2nhrA1r