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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