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This moon is doomed. Mars , the red planet named for the Roman god of war , has two tiny moons, Phobos and Deimos , whose names are derived from the Greek for Fear and Panic . These Martian moons may well be captured asteroids originating in the main asteroid belt between Mars and Jupiter or perhaps from even more distant reaches of our Solar System . The larger moon, Phobos , is indeed seen to be a cratered, asteroid-like object in this stunning color image from the robotic Mars Reconnaissance Orbiter , which can image objects as small as 10 meters. But Phobos orbits so close to Mars - about 5,800 kilometers above the surface compared to 400,000 kilometers for our Moon - that gravitational tidal forces are dragging it down. In perhaps 50 million years, Phobos is expected to disintegrate into a ring of debris. from NASA https://ift.tt/Nt3DBYS

Eight billion people are about to disappear in this snapshot from space taken on 2022 November 21. On the sixth day of the Artemis I mission , their home world is setting behind the Moon's bright edge as viewed by an external camera on the outbound Orion spacecraft. Orion was headed for a powered flyby that took it to within 130 kilometers of the lunar surface. Velocity gained in the flyby maneuver was used to reach a distant retrograde orbit around the Moon. That orbit is considered distant because it's another 92,000 kilometers beyond the Moon, and retrograde because the spacecraft orbited in the opposite direction of the Moon's orbit around planet Earth. Swinging around the Moon , Orion reached a maximum distance (just over 400,000 kilometers) from Earth on 2022 November 28, exceeding a record set by Apollo 13 for most distant spacecraft designed for human space exploration . The Artemis II mission , carrying 4 astronauts around the moon and back again, is due to l...

Very faint planetary nebula Abell 7 is about 1,800 light-years distant. It lies just south of Orion in planet Earth's skies toward the constellation Lepus, The Hare . Posing with scattered Milky Way stars, its generally simple spherical shape about 8 light-years in diameter is revealed in this deep telescopic image. The beautiful and complex shapes seen within the cosmic cloud are visually enhanced by the use of long exposures and narrowband filters that capture emission from hydrogen and oxygen atoms. Otherwise Abell 7 would be much too faint to be appreciated by eye . A planetary nebula represents a very brief final phase in stellar evolution that our own Sun will experience 5 billion years hence , as the nebula's central, once sun-like star shrugs off its outer layers. Abell 7 itself is estimated to be 20,000 years old. But its central star, seen here as a fading white dwarf , is some 10 billion years old. from NASA https://ift.tt/Ohjc6ex

The silhouette of an intriguing dark nebula inhabits this cosmic scene . Lynds' Dark Nebula ( LDN ) 1622 appears against a faint background of glowing hydrogen gas only visible in long telescopic exposures of the region. In contrast, a brighter reflection nebula, vdB 62, is more easily seen just above the dusty dark nebula. LDN 1622 lies near the plane of our Milky Way Galaxy, close on the sky to Barnard's Loop , a large cloud surrounding the rich complex of emission nebulae found in the Belt and Sword of Orion . With swept-back outlines, the obscuring dust of LDN 1622 is thought to lie at a similar distance, perhaps 1,500 light-years away. At that distance, this 3 degree wide field of view would span about 100 light-years. Young stars do lie hidden within the dark expanse and have been revealed in Spitzer Space telescope infrared images . Still, the foreboding visual appearance of LDN 1622 inspires its popular name, the Boogeyman Nebula . from NASA https://ift.tt/xU6Gct...

A mere 56 million light-years distant toward the southern constellation Fornax, NGC 1365 is an enormous barred spiral galaxy about 200,000 light-years in diameter. That's twice the size of our own barred spiral Milky Way. This sharp image from the James Webb Space Telescope 's Mid-Infrared Instrument (MIRI) reveals stunning details of this magnificent spiral in infrared light . Webb's field of view stretches about 60,000 light-years across NGC 1365, exploring the galaxy's core and bright newborn star clusters. The intricate network of dusty filaments and bubbles is created by young stars along spiral arms winding from the galaxy's central bar. Astronomers suspect the gravitational field of NGC 1365's bar plays a crucial role in the galaxy's evolution, funneling gas and dust into a star-forming maelstrom and ultimately feeding material into the active galaxy's central, supermassive black hole . from NASA https://ift.tt/hKA5tVp

The strangest moon in the Solar System is bright yellow. The featured picture , an attempt to show how Io would appear in the "true colors" perceptible to the average human eye, was taken in 1999 July by the Galileo spacecraft that orbited Jupiter from 1995 to 2003. Io's colors derive from sulfur and molten silicate rock . The unusual surface of Io is kept very young by its system of active volcanoes . The intense tidal gravity of Jupiter stretches Io and damps wobbles caused by Jupiter's other Galilean moons . The resulting friction greatly heats Io 's interior, causing molten rock to explode through the surface. Io's volcanoes are so active that they are effectively turning the whole moon inside out. Some of Io 's volcanic lava is so hot it glows in the dark . from NASA https://ift.tt/iq7juOn

What powers this unusual nebula? CTB 1 is the expanding gas shell that was left when a massive star toward the constellation of Cassiopeia exploded about 10,000 years ago. The star likely detonated when it ran out of elements, near its core, that could create stabilizing pressure with nuclear fusion . The resulting supernova remnant , nicknamed the Medulla Nebula for its brain-like shape , still glows in visible light because of the heat generated by its collision with confining interstellar gas . Why the nebula also glows in X-ray light , though, remains a topic of research . One hypothesis holds that an energetic pulsar was created and powers the nebula with a fast outwardly moving wind. Following this lead, a pulsar was found in radio waves that appears to have been expelled by the supernova explosion at over 1000 kilometers per second. Although the Medulla Nebula appears as large as a full moon , it is so faint that it took 84-hours of exposure with a small telescope in ...

This infrared view of Jupiter by Webb is illuminating. High-resolution infrared images of Jupiter from the James Webb Space Telescope (Webb) reveal, for example, differences between high-floating bright clouds -- including the Great Red Spot -- and low-lying dark clouds. Also clearly visible in the featured Webb image are Jupiter's dust ring , bright auroras at the poles , and Jupiter's moons Amalthea and Adrastea . The footprint of large volcanic moon Io 's magnetic funneling of charged particles onto Jupiter is also visible in the southern aurora. Some objects are so bright that light noticeably diffracts around Webb's optics creating streaks . Webb, which orbits the Sun near the Earth, has a mirror over six meters across making it the largest astronomical telescope ever launched -- with over six times more light-collecting area than Hubble . from NASA https://ift.tt/4WmeXvq

Apollo 14's Lunar Module Antares landed on the Moon on February 5, 1971. Toward the end of the stay astronaut Ed Mitchell snapped a series of photos of the lunar surface while looking out a window, assembled into this detailed mosaic by Apollo Lunar Surface Journal editor Eric Jones. The view looks across the Fra Mauro highlands to the northwest of the landing site after the Apollo 14 astronauts had completed their second and final walk on the Moon . Prominent in the foreground is their Modular Equipment Transporter, a two-wheeled, rickshaw-like device used to carry tools and samples. Near the horizon at top center is a 1.5 meter wide boulder dubbed Turtle rock. In the shallow crater below Turtle rock is the long white handle of a sampling instrument, thrown there javelin-style by Mitchell. Mitchell's fellow moonwalker and first American in space, Alan Shepard , also used a makeshift six iron to hit two golf balls . One of Shepard's golf balls is just visible as a wh...

These cosmic clouds have blossomed 1,300 light-years away in the fertile starfields of the constellation Cepheus . Called the Iris Nebula, NGC 7023 is not the only nebula to evoke the imagery of flowers . Still, this deep telescopic image shows off the Iris Nebula's range of colors and symmetries embedded in surrounding fields of interstellar dust. Within the Iris itself, dusty nebular material surrounds a hot, young star. The dominant color of the brighter reflection nebula is blue, characteristic of dust grains reflecting starlight. Central filaments of the reflection nebula glow with a faint reddish photoluminescence as some dust grains effectively convert the star's invisible ultraviolet radiation to visible red light. Infrared observations indicate that this nebula contains complex carbon molecules known as PAHs . The dusty blue petals of the Iris Nebula span about six light-years. from NASA https://ift.tt/26ZexFp

The dark-floored, 95 kilometer wide crater Plato and sunlit peaks of the lunar Alps (Montes Alpes) are highlighted in this this sharp telescopic snapshot of the Moon's surface. While the Alps of planet Earth were uplifted over millions of years as continental plates slowly collided, the lunar Alps were likely formed by a sudden collision that created the giant impact basin known as the Mare Imbrium or Sea of Rains. The mare's generally smooth, lava-flooded floor is seen below the bordering mountain range. The prominent straight feature cutting through the mountains is the lunar Alpine Valley (Vallis Alpes). Joining the Mare Imbrium and northern Mare Frigoris (Sea of Cold) the valley extends toward the upper right, about 160 kilometers long and up to 10 kilometers wide. Of course, the large, bright lunar alpine mountain below and right of Plato crater is named Mont Blanc . Lacking an atmosphere, not to mention snow , the lunar Alps are probably not an ideal location for ...

The Whirlpool Galaxy is a classic spiral galaxy. At only 30 million light years distant and fully 60 thousand light years across, M51 , also known as NGC 5194, is one of the brightest and most picturesque galaxies on the sky. The featured deep image is a digital combination of images taken in different colors over 58 hours with a telescope from Lijiang , China . Anyone with a good pair of binoculars , however, can see this Whirlpool toward the constellation of the Hunting Dogs ( Canes Venatici ). M51 is a spiral galaxy of type Sc and is the dominant member of a whole group of galaxies . Astronomers speculate that M51 's spiral structure is primarily due to its gravitational interaction with the smaller galaxy just above it. from NASA https://ift.tt/sDfaSrJ

What's happening to this meteor? It is shedding its outer layers as it passes through the Earth's atmosphere and heats up. The sudden high temperatures not only cause the bright glow along the dramatic streak but also melt and vaporize the meteor's component rock and ice , creating dust. Wind in the atmosphere typically blows this dust away over the next few seconds, leaving no visible trace after only a few minutes. Much of this dust will eventually settle down to the Earth . The featured image was captured in mid-December, coincident with the Geminids meteor shower . On the upper left is Sirius , the brightest star in the night sky , while in the foreground is fog-engulfed Huangshan , the Yellow Mountains of eastern China . from NASA https://ift.tt/qEFrOSR

This floating ring is the size of a galaxy. In fact, it is a galaxy -- or at least part of one: the photogenic Sombrero Galaxy , one of the largest galaxies in the nearby Virgo Cluster of Galaxies . The dark band of dust that obscures the mid-section of the Sombrero Galaxy in visible light actually glows brightly in infrared light. The featured image , digitally sharpened , shows the infrared glow, recently recorded by the orbiting Spitzer Space Telescope , superposed in false-color on an existing image taken by NASA's Hubble Space Telescope in visible light. The Sombrero Galaxy, also known as M104 , spans about 50,000 light years and lies 28 million light years away. M104 can be seen with a small telescope in the direction of the constellation Virgo . from NASA https://ift.tt/LEintJ6

Jupiter reaches its 2026 opposition today, January 10. That puts our Solar System's most massive planet opposite the Sun and near its closest and brightest for viewing from planet Earth. In fact, captured only 3 days ago this sharp telescopic snapshot reveals excellent details of the ruling gas giant's swirling cloudtops , in light zones and dark belts girdling the rapidly rotating outer planet. Jupiter's famous, persistent anticyclonic vortex, known as the Great Red Spot , is south of the equator at the lower right. But two smaller red spots are also visible, one near the top in the northernmost zone, and one close to Jupiter's south pole. And while Jupiter's Great Red Spot is known to be shrinking , it's still about the size of the Earth itself. from NASA https://ift.tt/Q0zFTZc

Both Moon and Sun create beautiful ice halos in planet Earth's sky. In fact, the two brightest celestial beacons are each surrounded by a complex of ice halos in these photos of the sky above Chamonix-Mont-Blanc in France. The panels were recorded one night (left) and the following day at the end of December 2025. Similar ice halos appear in moonlight and sunlight because they are all formed through the geometry of flat, hexagonal ice crystals. The ice crystals reflect and refract light as they flutter in the cold atmosphere above the mountain resort. In the pictures both Moon and Sun are surrounded by a more commonly seen 22 degree circular halo. Bright and sometimes colorful patches at the intersections of the 22 degree circular halos with the indicated parselenic and parhelic arcs are also known as Moon dogs and Sun dogs . from NASA https://ift.tt/q2yVCMt

Similar in size to large, bright spiral galaxies in our neighborhood, IC 342 is a mere 10 million light-years distant toward the long-necked, northern constellation Camelopardalis . A sprawling island universe , IC 342 would otherwise be a prominent galaxy in our night sky, but it is hidden from clear view and only glimpsed through the veil of stars, gas and dust clouds along the plane of our own Milky Way galaxy . Even though IC 342's light is dimmed and reddened by intervening cosmic clouds , this sharp telescopic image traces the galaxy's own obscuring dust, young star clusters, and glowing star forming regions along spiral arms that wind far from the galaxy's core . IC 342 has undergone a recent burst of star formation activity and is close enough to have influenced the evolution of the local group of galaxies and the Milky Way. from NASA https://ift.tt/xUn3u1d

Its popular nickname is the Spaghetti Nebula. Officially cataloged as Simeis 147 and Sharpless 2-240, it is easy to get lost following the looping and twisting filaments of this intricate supernova remnant . Seen toward the boundary of the constellations of the Bull ( Taurus ) and the Charioteer ( Auriga ), the impressive gas structure covers nearly 3 degrees on the sky, equivalent to 6 full moons . That's about 150 light-year s at the stellar debris cloud's estimated distance of 3,000 light-years. The supernova remnant has an estimated age of about 40,000 years, meaning light from this powerful stellar explosion first reached the Earth when woolly mammoths roamed free. Besides the expanding remnant, this cosmic catastrophe left behind a pulsar , a fast-spinning neutron star that is the remnant of the original star's core. The featured image was captured last month from Forca Canapine , Italy . from NASA https://ift.tt/zuyR6W8

How complex is Jupiter? NASA's Juno mission to Jupiter is finding the Jovian giant to be more complicated than expected . Jupiter's magnetic field has been discovered to be much different from our Earth's simple dipole field , showing several poles embedded in a complicated network more convoluted in the north than the south. Further, Juno's radio measurements show that Jupiter's atmosphere shows structure well below the upper cloud deck -- even hundreds of kilometers deep. Jupiter 's newfound complexity is evident also in southern clouds, as shown in the texture and color enhanced featured image taken last month. There, planet-circling zones and belts that dominate near the equator decay into a complex miasma of continent-sized storm swirls. Juno continues in its looping elliptical orbit, swooping near the huge planet every month and exploring a slightly different sector each time around. from NASA https://ift.tt/0iCszD6

How was the unusual Red Rectangle nebula created? At the nebula's center is an aging binary star system that surely powers the nebula but does not, as yet, explain its colors. The unusual shape of the Red Rectangle is likely due to a thick dust torus which pinches the otherwise spherical outflow into tip-touching cone shapes . Because we view the torus edge-on, the boundary edges of the cone shape s seem to form an X . The distinct rungs suggest the outflow occurs in fits and starts. The unusual colors of the nebula are less well understood , however, and speculation holds that they are partly provided by hydrocarbon molecules that may actually be building blocks for organic life. The Red Rectangle nebula lies about 2,300 light years away towards the constellation of the Unicorn ( Monoceros ). The nebula is shown here in great detail as a reprocessed image from Hubble Space Telescope . In a few million years, as one of the central stars becomes further depleted of nuc...

Most galaxies have a single nucleus -- does this galaxy have four? The strange answer leads astronomers to conclude that the nucleus of the surrounding galaxy is not even visible in this image . The central cloverleaf is rather light emitted from a background quasar . The gravitational field of the visible foreground galaxy breaks light from this distant quasar into four distinct images. The quasar must be properly aligned behind the center of a massive galaxy for a mirage like this to be evident. The general effect is known as gravitational lensing , and this specific case is known as the Einstein Cross . Stranger still, the images of the Einstein Cross vary in relative brightness, enhanced occasionally by the additional gravitational microlensing effect of specific stars in the foreground galaxy. from NASA https://ift.tt/U9a3DNq

The Full Moon is the brightest lunar phase, and tonight you can stand in the light of the first Full Moon of 2026. In fact, the Moon's full phase occurs on January 3 at 10:03 UTC, while only about 7 hours later planet Earth reaches its 2026 perihelion, the closest point in its elliptical orbit around the Sun, at 17:16 UTC. January's Full Moon was also not far from its own perigee, or closest approach to planet Earth. For this lunation the Moon's perigee was on January 1 at 21:44 UTC. You can also spot planet Jupiter, near its brightest for 2026 and close on the sky to the Full Moon tonight. But while you're out skygazing don't forget to look for rare, bright fireballs from the Quadrantid meteor shower. from NASA https://ift.tt/sXNp24u

In 2011, on January 20, NASA's NanoSail-D2 unfurled a very thin and very reflective 10 square meter sail becoming the first solar sail spacecraft in low Earth orbit. Often considered the stuff of science fiction , sailing through space was suggested 400 years ago by astronomer Johannes Kepler, who had observed comet tails blown by the solar wind. But modern solar sail spacecraft designs, like NanoSail-D2, Japan's interplanetary spacecraft IKAROS , or the Planetary Society's Lightsail A , rely on the small but continuous pressure from sunlight itself for thrust. Glinting in the sunlight as it circled planet Earth, NanoSail-D2's solar sail was periodically bright and visible to the eye. These remarkably detailed images were captured by manually tracking the orbiting solar sail spacecraft with a small telescope. from NASA https://ift.tt/ARgnPkE

Cycle 25 solar maximum made 2025 a great year for aurora borealis (or aurora australis ) on planet Earth. And the high level of solar activity should extend into 2026. So, while you're celebrating the arrival of the new year, check out this spectacular auroral display that erupted in starry night skies over Kirkjufell , Iceland. The awesome auroral corona, energetic curtains of light streaming from directly overhead, was witnessed during a strong geomagnetic storm triggered by intense solar activity near the March 2025 equinox. This northland and skyscape captures the evocative display in a 21 frame panoramic mosaic. from NASA https://ift.tt/yBaIoXS

What created the Waterfall Nebula? The origin is still being researched. The structure, officially designated Herbig-Haro 222, appears in the region of NGC 1999 in the Great Orion Molecular Cloud complex. The elongated gaseous stream stretches about ten light years but appears similar to a long waterfall on Earth. Recent observations indicate that HH-222 is likely a gigantic gaseous bow shock , similar to a wave of water caused by a fast-moving ship. The origin of this shock wave is thought to be a jet outflow from the multiple star system V380 Orionis off the lower left of the frame. Therefore, gas does not flow along the waterfall, but rather the entire structure moves toward the upper right. The Waterfall Nebula lies about 1,500 light year s away toward the constellation of Orion. The featured image was captured earlier this month from El Sauce Observatory in Chile . from NASA https://ift.tt/ld2wTB8

Yes, but can your comet tail do this? No, and what you are seeing is not the tail of a comet . The picture features a cleverly overlayed time-lapse sequence of a group of satellites orbiting Earth together in June. Specifically, these are Starlink communications satellites in low Earth orbit reflecting back sunlight before sunrise to Inner Mongolia , China . Although the satellites appear to the human eye as points, the 20-second-long camera exposures caused them to appear as short streaks . Currently there are over 9000 Starlinks in orbit , with more being launched nearly every week. Other satellite constellations are also being planned. from NASA https://ift.tt/1PdOltW

This is the mess that is left when a star explodes. The Crab Nebula , the result of a supernova seen in 1054 AD , is filled with mysterious filaments. The filaments are not only tremendously complex but appear to have less mass than expelled in the original supernova and a higher speed than expected from a free explosion. The featured image was taken by an amateur astronomer in Leesburg , Florida , USA over three nights last month. It was captured in three primary colors but with extra detail provided by specific emission by hydrogen gas. The Crab Nebula spans about 10 light year s. In the Nebula's very center lies a pulsar: a neutron star as massive as the Sun but with only the size of a small town . The Crab Pulsar rotates about 30 times each second. from NASA https://ift.tt/gSczinN

Jewels don't shine this bright -- only stars do. And almost every spot in this jewel-box of an image from the Hubble Space Telescope is a star. Now, some stars are more red than our Sun , and some more blue -- but all of them are much farther away. Although it takes light about 8 minutes to reach Earth from the Sun, NGC 1898 is so far away that it takes light about 160,000 years to get here. This huge ball of stars, NGC 1898 , is called a globular cluster and resides in the central bar of the Large Magellanic Cloud (LMC) -- a satellite galaxy of our Milky Way Galaxy . The featured multi-colored image includes light from the infrared to the ultraviolet and was taken to help determine if the stars of NGC 1898 all formed at the same time or at different times. There are increasing indications that most globular clusters formed stars in stages , and that, in particular, stars from NGC 1898 formed shortly after ancient encounter s with the Small Magellanic Cloud (SMC) and ...

Awkward and angular looking, Apollo 17's lunar module Challenger was designed for flight in the near vacuum of space. Digitally enhanced and reprocessed, this picture taken from Apollo 17's command module America shows Challenger's ascent stage in lunar orbit. Small reaction control thrusters are at the sides of the moonship with the bell of the ascent rocket engine underneath. The hatch that allowed access to the lunar surface is seen at the front, with a round radar antenna at the top. Mission commander Gene Cernan is clearly visible through the triangular window. This spaceship performed gracefully, landing on the Moon and returning the Apollo astronauts to the orbiting command module in December of 1972. So where is Challenger now? While its descent stage remains at the Apollo 17 landing site in the Taurus-Littrow valley, the ascent stage pictured was intentionally crashed nearby after being jettisoned from the command module prior to the astronauts' return to...

Attention grabbing interstellar visitor 3I/ATLAS made its not-so-close flyby of our fair planet on December 19 at a distance of 1.8 astronomical units. That's about 900 light-seconds. Still, this deep exposure captures the comet from another star system as it gently swept across a faint background of stars in the constellation Leo about 4 days earlier, on the night of December 15. Though faint, colors emphasized in the image data, show off the comet's yellowish dust tail and bluish ion tail along with a greenish tinged coma. And even while scrutinized by arrays of telescopes and spacecraft from planet Earth, 3I ATLAS is headed out of the Solar System. It's presently moving outward along a hyperbolic trajectory at about 64 kilometers per second relative to the Sun, too fast to be bound the Sun's gravity. from NASA https://ift.tt/VOerFWJ

A star forming region cataloged as NGC 2264 , this beautiful but complex arrangement of interstellar gas and dust is about 2,700 light-years distant in the faint but fanciful constellation Monoceros, the Unicorn . Seen toward the celestial equator and near the plane of our Milky Way galaxy, the seasonal skyscape mixes reddish emission nebulae excited by energetic light from newborn stars with dark interstellar dust clouds. Where the otherwise obscuring dust clouds lie close to the hot, young stars, they also reflect starlight, forming blue reflection nebulae . In fact, bright variable star S Monocerotis is immersed in a blue-tinted haze near center. Arrayed with a simple triangular outline above S Monocerotis , the stars of NGC 2264 are popularly known as the Christmas Tree star cluster . Carved by energetic starlight, the Cone Nebula sits upside down at the apex of this cosmic Christmas tree while the dusty, convoluted pelt of glowing gas and dust under the tree is called the Fox...

What are these little red dots (LRDs)? Nobody knows. Discovered only last year, hundreds of LRDs have now been found by the James Webb Space Telescope in the early universe . Although extremely faint, LRDs are now frequently identified in deep observations made for other purposes. A wide-ranging debate is raging about what LRDs may be and what importance they may have. Possible origin hypotheses include accreting supermassive black holes inside clouds of gas and dust, bursts of star formation in young dust-reddened galaxies , and dark matter powered gas clouds . The highlighted images show six nearly featureless LRDs listed under the JWST program that found them, and z, a distance indicator called cosmological redshift . Additionally, searches are underway in our nearby universe to try to find whatever previous LRDs might have become today . from NASA https://ift.tt/KY5rHi0

What's happening in the sky? Lightning . The most commonly seen type of lightning involves flashes of bright white light between clouds. Over the past 50 years, though, other types of upper-atmospheric lightning have been confirmed, including tentacled red sprites and ringed ELVES . Although both last only a small fraction of a second, sprites are brighter and easier to photograph than their more common electrical-discharge cousins. ELVES are rapidly expanding rings that are thought to be created when an electromagnetic pulse shoots upward from charged clouds and impacts the ionosphere , causing nitrogen molecules to glow. Capturing either form of lightning takes patience and experience -- capturing them both together , since they usually occur separately, is rare. The featured image is a frame from a video recorded from Possagno , Italy late last month above a distant thunderstorm over the Adriatic Sea . from NASA https://ift.tt/duAD0RT

Yesterday the Sun reached its southernmost point in planet Earth's sky. Called a solstice , many cultures mark yesterday's date as a change of seasons -- from autumn to winter in Earth 's Northern Hemisphere and from spring to summer in Earth's Southern Hemisphere . The featured image was taken just before the longest night of the 2025 northern year at Stonehenge in United Kingdom . There, through stones precisely placed 4,500 years ago, a 4.5 billion year old large glowing orb is seen setting. Even given the precession of the Earth's rotational axis over the millennia, the Sun continues to set over Stonehenge in an astronomically significant way . from NASA https://ift.tt/Q28KYrN

The word solstice is from the Latin for Sun and to pause or stand still. And in the days surrounding a solstice the Sun's annual north-south drift in planet Earth's sky does slow down, pause, and then reverse direction. So near the solstice the daily path of the Sun through the sky really doesn't change much. In fact, near the December solstice , the Sun's consistent, low arc through northern hemisphere skies, along with low surface temperatures, has left a noticeable imprint on this path to the mountain town of Peaio in northern Italy. The morning frost on the road has melted away only where the sunlight was able to reach the ground. But it remains in the areas persistently shadowed by the fence, tattooing in frost an image of the fence on the asphalt surface. from NASA https://ift.tt/Iuf62tk

When the Moon is at its first quarter phase, the Sun rises along the Montes Caucasus as seen from the lunar surface. The lunar mountain range casts the magnificent, spire-like shadows in this telescopic view from planet Earth, looking along the lunar terminator or the boundary between lunar night and day. Named for Earth's own Caucasus Mountains, the rugged lunar Montes Caucasus peaks, up to 6 kilometers high, are located between the smooth Mare Imbrium to the west and Mare Serenitatis to the east. Still mostly in shadow in this first quarter lunarscape , at the left (west) impact craters reflect the light of the rising Sun along their outer, eastern crater walls. from NASA https://ift.tt/qCkMUt0

Jupiter , the Solar System's ruling gas giant, is the brightest celestial beacon at the center of this composite night skyscape . The scene was constructed by selecting the 40 exposures containing meteors from about 500 exposures made on the nights of December 13 and 14, near peak activity for this year's annual Geminid meteor shower . With each selected exposure registered in the night sky above Alentejo, Portugal, planet Earth, it does look like the meteors are streaming away from Jupiter. But the apparent radiant of the Geminid meteors is actually closer to bright star Castor, in the shower's eponymous constellation Gemini. In this frame that's just a little above and left of the Solar System's most massive planet. Still, the parent body of Geminid meteors is known to be rocky, near-Earth asteroid 3200 Phaethon . And the orbit of Phaethon itself is influenced by the gravitational attraction exerted by massive Jupiter, in concert with planets of the inner So...

Stars are forming in the Soul of the Queen of Aethopia . More specifically, a large star forming region called the Soul Nebula can be found in the direction of the constellation Cassiopeia , whom Greek mythology credits as the vain wife of a King who long ago ruled lands surrounding the upper Nile river. Also known as Westerhout 5 (W5), the Soul Nebula houses several open clusters of stars , ridges and pillars darkened by cosmic dust , and huge evacuated bubbles formed by the winds of young massive stars . Located about 6,500 light years away, the Soul Nebula spans about 100 light years and is usually imaged next to its celestial neighbor the Heart Nebula (IC 1805). The featured image , taken from near Nashville, Tennessee, USA, is a composite of 234 hours of exposures made in different colors: red as emitted by hydrogen gas, yellow as emitted by sulfur , and blue as emitted by oxygen . from NASA https://ift.tt/Emj0AVa

What’s happening over that tree? Two very different things. On the left is the Andromeda galaxy , an object that is older than humanity and will last billions of years into the future. Andromeda ( M31 ) is similar in size and shape to our own Milky Way Galaxy . On the right is a red sprite , a type of lightning that lasts a fraction of a second and occurs above violent thunderstorms . Red sprites were verified as real atmospheric phenomena only about 35 years ago. The tree in the center is a boab , which may live for as long as a thousand years. Boab trees grow naturally in Australia and Africa and are known for being able to store large amounts of water: up to 100,000 liters. The featured image was captured last month near Derby in Western Australia . from NASA https://ift.tt/ILOu5i4

Where are all of these meteors coming from? In terms of direction on the sky, the pointed answer is the constellation of Gemini. That is why the major meteor shower in December is known as the Geminids -- because shower meteors all appear to come from a radiant toward Gemini . Three dimensionally, however, sand-sized debris expelled from the unusual asteroid 3200 Phaethon follows a well-defined orbit about our Sun, and the part of the orbit that approaches Earth is superposed in front of the constellation of Gemini . Therefore, when Earth crosses this orbit , the radiant point of falling debris appears in Gemini. Featured here is a composite of many images taken over the past few days through dark skies from Slovakia and capturing the snow-covered peaks of the Belianske Tatra mountains Numerous bright meteor streaks from the Geminids meteor shower are visible. Orion is visible above the horizon, while the bright star nearest the radiant is Castor . from NASA https://i...

What would it be like to fly over the largest moon in the Solar System ? In 2021, the robotic Juno spacecraft flew past Jupiter 's huge moon Ganymede and took images that have been digitally constructed into a detailed flyby. As the featured video begins, Juno swoops over the two-toned surface of the 2,000-km wide moon, revealing an icy alien landscape filled with grooves and craters. The grooves are likely caused by shifting surface plates, while the craters are caused by violent impacts . Continuing on in its orbit, Juno then performed its 34th close pass over Jupiter's clouds. The digitally-constructed video shows numerous swirling clouds in the north, colorful planet-circling zones and bands across the middle -- featuring several white-oval cloud s from the String of Pearls , and finally more swirling clouds in the south. from NASA https://ift.tt/3FmRSMv

On December 5, 2022, a camera on board the uncrewed Orion spacecraft captured this view as Orion approached its return powered flyby of the Moon. Beyond one of Orion's extended solar arrays lies dark, smooth, terrain along the western edge of the Oceanus Procellarum. Prominent on the lunar nearside Oceanus Procellarum , the Ocean of Storms, is the largest of the Moon's lava-flooded maria . The lunar terminator, the shadow line between lunar night and day, runs along the left of this frame. The 41 kilometer diameter crater Marius is top center, with ray crater Kepler peeking in at the edge, just right of the solar array wing. Kepler's bright rays extend to the north and west, reaching the dark-floored Marius . By December 11, 2022 the Orion spacecraft had returned to its home world . The historic Artemis 1 mission ended with Orion's successful splashdown in planet Earth's water-flooded Pacific Ocean. from NASA https://ift.tt/ZhqCoxA

In a Finnish myth , when an arctic fox runs so fast that its bushy tail brushes the mountains, flaming sparks are cast into the heavens creating the northern lights. In fact the Finnish word "revontulet", a name for the aurora borealis or northern lights , can be translated as fire fox. So that evocative myth took on a special significance for the photographer of this northern night skyscape from Finnish Lapland near Kilpisjarvi Lake. The snowy scene is illuminated by moonlight. Saana, an iconic fell or mountain of Lapland, rises at the right in the background. But as the beautiful nothern lights danced overhead, the wild fire fox in the foreground enthusiastically ran around the photographer and his equipment, making it difficult to capture in this lucky single shot. from NASA https://ift.tt/Slb0GKo

Large galaxies grow by eating small ones. Even our own galaxy engages in a sort of galactic cannibalism , absorbing small galaxies that are too close and are captured by the Milky Way's gravity. In fact, the practice is common in the universe and illustrated by this striking pair of interacting galaxies from the banks of the southern constellation Eridanus , The River . Located over 50 million light years away, the large, distorted spiral NGC 1532 is seen locked in a gravitational struggle with dwarf galaxy NGC 1531, a struggle the smaller galaxy will eventually lose . Seen nearly edge-on, in this sharp image spiral NGC 1532 spans about 100,000 light-years. The NGC 1532/1531 pair is thought to be similar to the well-studied system of face-on spiral and small companion known as M51 . from NASA https://ift.tt/PIXrCLG

Sculpted by stellar winds and radiation, this dusty interstellar molecular cloud has by chance has assumed an immediately recognizable shape. Fittingly known as The Horsehead Nebula , it lies some 1,500 light-years distant, embedded in the vast Orion cloud complex. About five light-years "tall," the dark cloud is cataloged as Barnard 33, first identified on a photographic plate taken in the late 19th century. B33 is visible primarily because its obscuring dust is silhouetted against the glow of emission nebula IC 434. Hubble space telescope images from the early 21st century find young stars forming within B33. Of course, the magnificent interstellar cloud will slowly shift its apparent shape over the next few million years. But for now the Horsehead Nebula is a rewarding though difficult object to view with small telescopes from planet Earth . from NASA https://ift.tt/HEr35gh

This cosmic close-up looks deep inside the Soul Nebula. The dark and brooding dust clouds outlined by bright ridges of glowing gas are cataloged as IC 1871. About 25 light-year s across, the telescopic field of view spans only a small part of the much larger Heart and Soul nebulae. At an estimated distance of 6,500 light-years, the star-forming complex lies within the Perseus spiral arm of the Milky Way , seen in planet Earth's skies toward the constellation of the Queen of Aethiopia ( Cassiopeia ). An example of triggered star formation , the dense star-forming clouds of IC 1871 are themselves sculpted by the intense winds and radiation of the region's massive young stars. This color image adopts a palette made popular in Hubble images of star-forming regions. from NASA https://ift.tt/AL6doB7

Many wonders are visible when flying over the Earth at night. Such visual spectacles occur every day for astronauts in low Earth orbit, but the featured video captured several from the International Space Station (ISS) in 2011 and set them to rousing music. Passing below are white clouds , orange city lights , lightning flashes in thunderstorm s, and dark blue seas . On the horizon is the golden haze of Earth's thin atmosphere , frequently decorated by dancing auroras as the video progresses. The green parts of auroras typically remain below the space station, but the station flies right through the red and purple auroral peaks. Solar panels of the ISS are seen around the frame edges. The ominous wave of approaching brightness at the end of each sequence is just the dawn of the sunlit half of Earth , a dawn that occurs every 90 minutes. from NASA https://ift.tt/4AwenmK

It is still not known why the Sun's light is missing some colors. Here are all the visible colors of the Sun , produced by passing the Sun's light through a prism -like device. The spectrum was created at the McMath-Pierce Solar Observatory and shows, first off, that although our white -appearing Sun emits light of nearly every color , it appears brightest in yellow-green light. The dark patches in the featured spectrum arise from gas at or above the Sun's surface absorbing sunlight emitted below. Since different types of gas absorb different colors of light , it is possible to determine what gasses compose the Sun. Helium , for example, was first discovered in 1868 on a solar spectrum and only later found here on Earth . Today, the majority of spectral absorption lines have been identified - but not all . from NASA https://ift.tt/isXW58J

Fifty three years ago , in December of 1972, Apollo 17 astronauts Eugene Cernan and Harrison Schmitt spent about 75 hours on the Moon exploring the Taurus-Littrow valley, while colleague Ronald Evans orbited overhead . This snapshot from another world was taken by Cernan as he and Schmitt roamed the lunar valley's floor. The image shows Schmitt next to the lunar rover parked at the southeast rim of Shorty Crater . That location is near the spot where geologist Schmitt discovered orange lunar soil. The Apollo 17 crew returned with 110 kilograms of rock and soil samples , more than was returned from any of the other lunar landing sites. And for now , Cernan and Schmitt are the last to walk on the Moon . from NASA https://ift.tt/dOi4y5Z

Blasting outward from variable star KX Andromedae, these stunning bipolar jets are 19 light-years long. Recently discovered , they are revealed in unprecedented detail in this deep telescopic image centered on KX And and composed from over 692 hours of combined image data . In fact, KX And is spectroscopically found to be an interacting binary star system consisting of a bright, hot B-type star with a swollen cool giant star as its co-orbiting, close companion. The stellar material from the cool giant star is likely being transferred to the hot B-type star through an accretion disk , with spectacular symmetric jets driven outward perpendicular to the disk itself. The known distance to KX And of 2,500 light-years, angular size of the jets, and estimated inclination of the accretion disk lead to the size estimate for each jet of an astonishing 19 light-years . from NASA https://ift.tt/idAcswl