Deep Sky Creations

In 185 AD, Chinese astronomers recorded the appearance of a new star in the Nanmen asterism. That part of the sky is identified with part of the southern constellation Centaurus on modern star charts. In fact, the new star was reported to be visible to the naked eye for months before it faded from view, and is now thought to be the earliest recorded supernova. In this 21st century telescopic image, the wispy outlines of a faint emission nebula recognized as the remnant of that historical stellar explosion can be traced against a starry background. The ragged but roughly circular extent of the nebula, cataloged as RCW 86, represents interstellar gas ionized by the supernova's still expanding shock wave. Space-based images indicate an abundance of the element iron in RCW 86 and the absence of a neutron star or pulsar within the remnant, suggesting that the original supernova was Type Ia. Unlike the core collapse supernova explosion of a massive star, a Type Ia supernova is a thermonuclear detonation on a white dwarf star that has accreted material from its companion in a binary star system. Near the plane of our Milky Way galaxy and larger than the full moon on the sky this supernova remnant is too faint to be seen by eye though. RCW 86 is some 8,000 light-years distant and around 100 light-years across.

Have you ever seen another galaxy with your own eyes? The featured image shows the Large Magellanic Cloud (LMC), one of the closest neighbors of our Milky Way. If you are anywhere south of latitude 20° N (but the further south, the better), you can see it with the unaided eye if you go to a dark sky location, away from big cities and light polution. It is a dwarf irregular galaxy about 163,000 light-years away, and a member of our Local Group of galaxies. Despite being small, with a total mass approximately equivalent to 10% - 20% of the mass of the Milky Way, the LMC is very actively forming stars. This is likely due in part to the gravitational push and pull of tides caused by the Milky Way on the LMC. Some astronomers have predicted that it will collide with the Milky Way in in about 2 billion years.

The Southern Crown (Corona Australis) dazzles with young and ancient celestial jewels. The Corona Australis Cloud is a collage of reflection and emission nebulae on the left of today’s image. At 430 light years away, this cloud is one of the closest star-forming regions to Earth. It contains gas cool enough (-260 Celsius or -440 Fahrenheit) to collapse into protostars. Recently formed stars paint blue hues across the cloud as their light reflects off surrounding material. The waltz of the R Coronae Australis binary system stirs up the nebula NGC 6729. The younger of the pair ionizes nearby gas with its ultraviolet light, causing it to glow. The Chandelier Cluster (NGC 6723) dangles from the top right, but is actually tens of thousands of light years farther away than its apparent star-forming neighbor. While NGC 6723 experienced multiple periods of star formation creating slightly younger stars, the chandelier twinkles with stars almost as old as the universe.

Is this a fossilized turtle on Mars? No. Although resembling a large Earth tortoise, this is a layered rock outcrop on Mars that is estimated to span about 15 meters, making it much larger than turtles on Earth. NASA’s robotic Curiosity rover came across this unusual mound, dubbed Miraflores, last month during its 4922nd Martian day exploring Mars. The small butte may survive because it was somehow more resistant to erosion than surrounding rock. More recent wind has now covered its top with orange Martian sand. Below the top shell, many layers of stratified rock are visible, possibly indicating a long history of intermittent wind-blown sand being deposited and then hardened by ground water. Similar wind-eroded layered landforms, such as yardangs in the Qaidam Desert of China, exist here on Earth. Curiosity and its companion rover Perseverance continue to investigate the ancient history of Mars as well as searching for signs of primeval life.

What's happening in the Statue of Liberty nebula? Bright stars and interesting molecules are forming and being liberated. The complex nebula resides in the star forming region called RCW 57, and besides the iconic monument, to some looks like a flying superhero or a weeping angel. This re-assigned color image showcases dense knots of dark interstellar dust, fields of glowing hydrogen gas ionized by these stars, and great loops of gas expelled by dying stars. A detailed study of NGC 3576, also known as NGC 3582 and NGC 3584, uncovered at least 33 massive stars in the end stages of formation, and the clear presence of the complex carbon molecules known as polycyclic aromatic hydrocarbons (PAHs). PAHs are thought to be created in the cooling gas of star forming regions, and their development in the Sun's formation nebula five billion years ago may have been an important step in the development of life on Earth. Jigsaw Star Statue: Astronomy Puzzle of the Day

A flying saucer from outer space crash-landed in the Utah desert after being tracked by radar and chased by helicopters. The year was 2004, and no space aliens were involved. The saucer, pictured here, was the Genesis sample return capsule, part of a human-made robot Genesis spaceship launched in 2001 by NASA itself to study the Sun. The unexpectedly hard landing at over 300 kilometers per hour occurred because the parachutes did not open as planned. The Genesis mission had been orbiting the Sun collecting solar wind particles that are usually deflected away by Earth's magnetic field. Despite the crash landing, many return samples remained in good enough condition to analyze. Genesis-related discoveries included new details about the composition of the Sun and how the abundance of some types of elements differ across the Solar System. These results have provided intriguing clues into details of how the Sun and planets formed billions of years ago. Almost Hyperspace: Random APOD Generator

At sunset, an alignment of rainbow and mountain shadow was captured in this remarkable snapshot. The stunning view was recorded from a fire lookout on Smith Peak in the Plumas National Forest near Portola, California on July 13. Still, near sunset it's no accident that the majestic mountain shadow seems to point to the center of the graceful rainbow arc. Due to perspective and the long line of sight the mountain shadow naturally forms a tapering triangular shape, its apex positioned at the point opposite the Sun on the horizon. Following thunderstorms in the region, the rainbow arched across the early evening sky, with its colorful and characteristic 42 degree arc formed as sunlight is refracted and reflected by the atmospheric water droplets. The geometric center of a rainbow arc lies at the antisolar point. And in this scene from the golden hour on planet Earth, that's also opposite the setting Sun along the distant horizon.

Comet 10P/Tempel 2 orbits the Sun once every 5.4 years. Currently visible in binoculars or small telescopes toward the constellation Capricornus, the periodic comet is captured in this sharp telescopic image from July 11 sporting a bright nuclear region and pretty greenish coma. Remarkably, a thin dust trail, not a typical dust tail, is also seen extending both east and west of the Tempel 2 nucleus. Unlike a comet dust tail, which tends to temporarily fan out in a direction away from the Sun, this dust trail is due to the residual dust shed during many past orbits along this ancient periodic comet's orbital plane. In fact, Tempel 2's dust trail may get a little narrower and brighter from our perspective as Earth crosses through the comet's orbital plane on July 20. Comet 10P/Tempel 2 will reach a perihelion on August 2, and make its closest approach to Earth on August 3.

This sparkling, colorful gemstone is a spiral galaxy, NGC 300. It is one of the closest spiral galaxies to Earth, only about 6 million light-years away. But does it really look like this? Here is a more standard portrait of it. This unusual image combines the light from the stars and dust within the galaxy with the light from ionized clouds of interstellar gas shown in red (Sulphur), green (Hydrogen) and blue (Oxygen). Combining red and green light in different proportions makes yellow or orange light, most visible in the image. Light from other ionized gases is also at work in neon signs, fluorescent tubes and street lights. These massive clouds of ionized gas are typically created by young, massive stars that produce high-energy ultraviolet radiation capable of ionizing the gas. Massive stars are short-lived, compared with lighter stars like our sun, and explode as supernovas at the end of their lives. Some of the colorful clouds in the image could be hiding supernova remnants.

Is there an angry Sith using force lightning in the Tatacoa Desert?  This is not science fiction, but a gigantic jet with multiple red streamers! Ordinary lightning occurs when thundercloud particles collide, lose their electrons, and build up negative charge at the cloud bottom.  The cloud’s negative charge repels negative charge deeper into the Earth, leaving Earth’s surface positively charged.  The opposite charges attract, reaching towards each other and superheating the air into a white strike of plasma.  A gigantic jet occurs when internal cloud discharge escapes upward through a weak positive shielding layer, and shoots up from the cloud in less than a second.  They extend up into the mesosphere where the air is too thin for thunder.  The streamers at the top may resemble red sprites and get their color from heated molecular nitrogen.  Note: The text of this APOD has been revised.

Why is this asteroid a double? Earlier this month the Japanese robotic spacecraft Hayabusa2 shot past asteroid 98943 Torifune and captured pictures. Although previous observations from distant Earth indicated that Torifune was oblong, Hayabusa2 found that Torifune actually has two joined lobes. With a length of about four soccer fields, this space rock frequently comes near the Earth as it orbits the Sun, although it is not a threat. Besides the two lobes, Torifune shows many large boulders, but, surprisingly, no obvious craters, likely because its surface is a pile of rubble. Like asteroid Arrokoth, it appears that each lobe formed separately before colliding and becoming stuck together. Hayabusa2 famously encountered asteroid Ryugu in 2018, and now heads for an encounter in 2031 with 1998 KY26, a smaller asteroid that rotates unusually fast and might have reservoirs of ice.

What's happening to galaxy NGC 474? The multiple layers of emission appear strangely complex given the relatively featureless appearance of the elliptical galaxy in less deep images. The cause of the shells is a topic of research, but they are possibly tidal tails related to debris left over from absorbing numerous small galaxies in the past billion years. Alternatively, the shells may be like ripples in a pond, where the ongoing collision with the spiral galaxy just to the right of NGC 474 is causing density waves to ripple through the galactic giant. Regardless of the actual cause, the featured image dramatically highlights the increasing evidence that the halos of some elliptical galaxies are surprisingly complicated. Similarly, the halo of our own Milky Way Galaxy is one example of such unexpected intricacies. NGC 474 spans about 250,000 light years and lies about 100 million light years distant toward the constellation of the Fish (Pisces).

Unlike most entries in Charles Messier's famous catalog of deep sky objects, M24 is not a bright galaxy, star cluster, or nebula. It's a gap in nearby, obscuring interstellar dust clouds that allows a view of the distant stars in the Sagittarius spiral arm of our Milky Way galaxy. Direct your gaze through this gap with binoculars or a small telescope and you are looking through a window over 300 light-years wide at stars some 10,000 light-years or more from Earth. Sometimes called the Small Sagittarius Star Cloud, M24's luminous stars stretch across this gorgeous interstellar scene. Spanning over four full moons on the sky toward the constellation Sagittarius, the telescopic field of view includes dark markings B92 and B93 near the center of M24, along with other clouds of dust and glowing nebulae toward the center of the Milky Way.

What looks as if it is going to swallow the great Pillars of Creation? The Eagle Nebula (M16) is not a bird, a plane, or Superman. M16 is actually a combination of several celestial objects. NGC 6611 is the young star cluster that appears to peak out beneath the Eagle’s “wings”. The ultraviolet light from these stars ionizes the surrounding gas, creating the emission nebula IC 4703. The Stellar Spire is seen reaching towards the Pillars of Creation from the left. Both are structures of cold gas and dust that are optimal for star formation. Some astronomers previously thought the Pillars of Creation had been evaporated away by a supernova. Because M16 is 6,000 light years away, we would not be able to see the Pillars’ destruction for thousands more years. However, there is no conclusive evidence of the theorized supernova, so the Pillars of Creation will likely continue to create stars for millions of years.

Thor not only has his own day (Thursday), but a helmet in the heavens. Popularly called Thor's Helmet, NGC 2359 is a hat-shaped cosmic cloud with wing-like appendages. Heroically sized even for a Norse god, Thor's Helmet is about 30 light-years across. In fact, the cosmic head-covering is more like an interstellar bubble, blown by a fast wind from the bright, massive star near the bubble's center. Known as a Wolf-Rayet star, the central star is an extremely hot giant thought to be in a brief, pre-supernova stage of evolution. NGC 2359 is located about 15,000 light-years away toward the constellation of the Great Overdog. This sharp image is a combination of deep images taken in light emitted by hydrogen (red) and oxygen (blue). The star in the center of Thor's Helmet is expected to explode in a spectacular supernova sometime within the next few thousand years. Sky Surprise: What picture did APOD feature on your birthday? (after 1995)

What happens to a comet as it leaves our inner Solar System? Now, the arrival of a comet into the inner Solar System is typically heralded with great fanfare and high hopes that the comet will become bright and photogenic. But on the way out, the comet's nucleus is less warmed by the Sun, less gas and dust are expelled, the bright coma around the nucleus shrinks and fades, and the tail length drops off. Many comets will then return to the outer Solar System and only return in hundreds or thousands of years. In contrast, some comets -- like Comet C/2025 R3 (PanSTARRS) -- receive a gravitational kick from the planets and so will never return. Pictured, Comet R3 PanSTARRs was imaged deeply many nights in early to mid-May near Cerro Paranal in Chile. Later images appear closer to the top and clearly show the shrinking ion tail. Comet R3 Gallery: Comet R3 PanSTARRS in 2026

It was visible around the world. The sunset conjunction of Jupiter (left) and Venus (right) in 2012 was visible almost no matter where you lived on Earth. Anyone on our planet with a clear western horizon at sunset could see them. That year, a creative photographer traveled away from the town lights of Szubin, Poland to photograph a near closest approach of the two planets. The bright planets were then separated by only three degrees and his daughter struck a humorous pose. A faint red sunset still glowed in the background. Jupiter and Venus are together again this week after sunset, passing within a degree of each other about two days from today.

A darkened and mysterious north polar region known to some as Mordor Macula caps this premier view of Charon, Pluto's largest moon. The high-resolution image was captured by the interplanetary space probe New Horizons near its closest approach to distant Pluto on July 14, 2015. The combined blue, red, and infrared image data was processed to enhance colors and follow variations in Charon's surface properties with a resolution of about 2.9 kilometers (1.8 miles). A stunning image of Charon's Pluto-facing hemisphere, it also features a clear view of an apparently moon-girdling belt of fractures and canyons that seems to separate smooth southern plains from varied northern terrain. Charon is 1,214 kilometers (754 miles) across. That's about 1/10th the size of planet Earth but a whopping 1/2 the diameter of Pluto itself, and makes it the largest satellite relative to its parent body in the Solar System. Still, the moon appears as a small bump at about the 1 o'clock position on Pluto's disk in the grainy, negative, telescopic picture inset at upper left. That image was used by James Christy and Robert Harrington at the U.S. Naval Observatory in Flagstaff to discover Charon in June of 1978.

Within our own Milky Way galaxy, two bright, spiky stars stand like sentinels in the foreground of this cosmic snapshot. Far beyond them are the galaxies of the Hydra Cluster. In fact, while the spiky foreground stars are hundreds of light-years distant, the Hydra Cluster galaxies are well over 100 million light-years away. Three large galaxies near the cluster center, two yellow ellipticals (NGC 3311, NGC 3309) and one prominent blue spiral (NGC 3312), are the dominant galaxies, each about 150,000 light-years in diameter. An intriguing overlapping galaxy pair cataloged as NGC 3314 lies above and left of NGC 3312. Also known as Abell 1060, the Hydra galaxy cluster is one of three large galaxy clusters within 200 million light-years of the Milky Way. In the nearby universe, galaxies are gravitationally bound into clusters which themselves are loosely bound into superclusters. Superclusters in turn are seen to align over even larger scales.

What is happening inside this unusual nebula? Planetary nebula Tc 1, captured here in exquisite detail by the James Webb Space Telescope, is the celestial site where buckyballs were first identified in 2010. Buckminsterfullerene — as buckyballs are officially called — is a molecule with 60 carbon atoms (C60) arranged in the shape of a soccer ball. The molecule is named for architect Buckminster Fuller because of its resemblance to the geodesic dome he helped popularize. Webb’s new data reveal where the C60 molecules live in this nebula, and the geometry is striking: they populate a thin spherical shell around the central star, visible here as the bright edge of the nebula’s glowing orange central region. Look closely near the nebula’s heart and a more perplexing feature emerges: a delicate structure shaped uncannily like an upside-down question mark, fitting punctuation for the many questions this nebula still poses.

Over 1000 years ago, Persian astronomer Abd al-Rahman al-Sufi published humanity’s oldest known record of the Andromeda Galaxy in "The Book of Fixed Stars" (Bodleian Library MS. Marsh 144 p. 167). 800 years later, Andromeda became the 31st entry in Charles Messier’s "Catalogue of Nebulae and Star Clusters". From “a small cloud” to “nebula” and now known to be our nearest major galaxy, Andromeda has remained a fundamental astronomical object. Today’s image, taken over 202 hours, shows how far we have come in our ability to observe our neighbor. The diffuse red and blue clouds are mostly foreground ionized hydrogen and oxygen well within our Milky Way. Pink-red clouds of hydrogen ionized by the energetic light of young stars trace the galaxy’s dusty spiral arms. M32 and M110 are satellite galaxies pictured orbiting the larger Andromeda. Despite its long history of observation through ancient unaided eyes to modern telescopes, Andromeda still holds countless secrets that astronomers will continue to search for, including how galaxies merge and evolve, as well as the nature of the dark matter that galaxies reside in. Teachers! the NASA/IPAC Teacher Archive Research Program is officially open for applications!

The explosion is over, but the consequences continue. About twelve thousand years ago, a relatively normal star in the constellation Vela suddenly exploded, creating a strange point of light briefly visible to humans living near the beginning of recorded history. The outer layers of the star crashed into the interstellar medium, driving a shock wave that is still visible today. The featured image, taken piecemeal over 60 hours from the Khomas Region of Namibia, captures some of that filamentary and gigantic shock in visible light, with details highlighted by hydrogen (red) and oxygen (blue) emissions. As gas flies away from the detonated star, it decays and reacts with the interstellar medium, producing light in many different colors and energy bands. Remaining at the center of the Vela Supernova Remnant is a pulsar, a star as dense as nuclear matter that spins around more than ten times in a single second. Explore the Universe: Random APOD Generator

Telescopic views of Saturn and its beautiful rings often make it the star of star parties. But this stunning view of the outer gas gaint planet's rings and night side just isn't possible from telescopes in the vicinity of planet Earth. Peering out from the inner Solar System they can only bring Saturn's day side into view. In fact, this image of Saturn's slender sunlit crescent with the planet's night shadow cast across its broad and complex ring system was captured by the robot spacecraft Cassini. After a seven year long journey from planet Earth, Cassini called Saturn orbit home for 13 years (from 2004 - 2017) before it was directed to dive into the atmosphere of the gas giant on September 15, 2017. This magnificent mosaic is composed of frames recorded by Cassini's wide-angle camera only two days before its grand final plunge. And Saturn's night will not be seen again until another spaceship from Earth calls.

Newborn stars are forming in the Eagle Nebula. They are gravitationally contracting in pillars of dense gas and dust. The intense radiation of these newly-formed bright stars is causing surrounding material to boil away. This image, taken with the Hubble Space Telescope in near infrared light, allows the viewer to see through much of the thick dust that makes the pillars opaque in visible light. The giant structures are light years in length and dubbed informally the Pillars of Creation. Associated with the open star cluster M16, the Eagle Nebula lies about 6,500 light years away. The Eagle Nebula is a satisfying target for small telescopes in a nebula-rich part of the sky toward the split constellation Serpens Cauda (the tail of the snake). Sky Surprise: What picture did APOD feature on your birthday? (after 1995)

What is so micro about tonight's blue micromoon? Just after sunset, a full moon will appear slightly smaller and dimmer than usual. The reason is that the Moon's fully illuminated phase occurs within a short time of apogee - when the Moon is farthest from the Earth in its elliptical orbit. In fact, tonight's micromoon will be the farthest, smallest, and dimmest Moon this year. But tonight's micromoon is notable for yet another reason: it is also a blue moon, meaning that it is the second full moon in the same month (moon-th). Pictured here, a supermoon -- when the full moon appears near its largest -- is compared to a micromoon as photographed from Kolkata, India in May and December of 2021. Although the next micromoon occurs next month, and the next blue moon at the end of 2028, the next blue micromoon will not occur until 2053.

A gorgeous spiral galaxy, Messier 104 is famous for its nearly edge-on profile featuring a broad ring of obscuring dust lanes. Seen in silhouette against an extensive central bulge of stars, the swath of cosmic dust lends a broad brimmed hat-like appearance to the galaxy suggesting a more popular moniker, the Sombrero Galaxy. Also known as NGC 4594, the Sombrero galaxy can be seen across the spectrum and is host to a central supermassive black hole. About 50,000 light-years across and 28 million light-years away, M104 is one of the largest galaxies at the southern edge of the Virgo Galaxy Cluster. Still, the spiky foreground stars in this field of view lie well within our own Milky Way. This broad view of the well-known galaxy was processed to reveal M104's extended halo, as well as a faint tidal stellar stream. It was captured by the Dark Energy Camera (DECam) on the Blanco 4-meter telescope at the Cerro Tololo Inter-American Observatory.

What do you see in this crystal ball? The featured image shows NGC 1514, known as the Crystal Ball Nebula, observed by the Gemini North telescope on Maunakea, in Hawai'i. NGC 1514 is 1,500 light-years away and was discovered by William Herschel in 1790. This planetary nebula is formed when a star becomes a red giant and ejects its outer gas layers. The ejected shell of gas is heated up by the core of the star to temperatures hotter than the surface of our Sun: that makes the gas shine, creating beautiful images like this one. The slightly asymmetrical shape of the Crystal Ball Nebula reveals a secret: the bright star in the center has a companion. As the two stars orbit each other with a period of about nine years, they shape the gas around them. In about 10,000 - 25,000 years the nebula will be dissipated by their stellar winds.

After the Crab Nebula, this giant star cluster is the second entry in 18th century astronomer Charles Messier's famous list of things that are not comets. M2 is one of the largest globular star clusters now known to roam the halo of our Milky Way galaxy. Though Messier originally described it as a nebula without stars, this stunning Hubble image resolves stars across the cluster's central 40 light-years. Its population of stars numbers close to 150,000, concentrated within a total diameter of around 175 light-years. About 55,000 light-years distant toward the constellation Aquarius, this ancient denizen of the Milky Way, also known as NGC 7089, is 13 billion years old. An extended stellar debris stream, a signature of past gravitational tidal disruption, was recently found to be associated with Messier 2.

This cosmic snapshot covers a field of view over twice as wide as the full Moon within the boundaries of the high-flying constellation Cygnus. Made using astronomical narrowband filters, the image highlights the bright edge of a ring-like nebula traced by the glow of ionized hydrogen and oxygen gas. Embedded in the region's expanse of interstellar clouds, the complex, glowing arcs are sections of shells of material swept up by the wind from Wolf-Rayet star WR 134, the brightest star near image center. Distance estimates put WR 134 about 6,000 light-years away, making this telescopic frame over 100 light-years across. Shedding their outer envelopes in powerful stellar winds, massive Wolf-Rayet stars have burned through their nuclear fuel at a prodigious rate and end their final phase of massive star evolution in a spectacular supernova. Their stellar winds and final supernova explosion enrich the interstellar material with heavy elements to be incorporated in future generations of stars.

This big beautiful spiral shines in X-ray light. It is about 20 times larger than our Galaxy. It belongs to Abell 2029, a galaxy cluster one billion light-years away. (To see only the galaxies, hover your cursor over the image, or follow this link.) Galaxy clusters are the largest structures in the universe that are supported by gravity. Abell 2029 is formed by thousands of galaxies, surrounded by a huge cloud of hot gas and the equivalent of hundreds of trillions times the mass of the Sun in dark matter. The spiral is made of gas, mostly hydrogen and helium, heated to tens of millions of degrees. It was found in a recent study that used data from NASA's Chandra X-ray Observatory to show that Abell 2029 had a collision with a smaller cluster four billion years ago. The collision affected the gravitational field and caused the intracluster gas to slosh, like wine moving in a wine glass, shaping the spiral.

A dark wolf lies in gum. No, this isn’t a riddle! Today's image features the Dark Wolf Nebula (Sandqvist–Lindroos 17), a spooky dust cloud embedded within the Gum 55 (RCW 113) Nebula in the Scorpius constellation. While dust is a pest to us, it serves a vital role in creating the necessary conditions for stars to be born. The Dark Wolf absorbs the intense ultraviolet and visible light emitted by young stars in Gum 55 and re-emits it at longer, mainly infrared, wavelengths. This prevents the higher energy light from heating up the gas in the region. When a region of gas is cool enough, gravity takes over and causes the gas to collapse into a star. Not only does dust act as an interstellar thermostat, but it is also the meet-cute for single hydrogen atoms forming molecular hydrogen, the building block for stars. The seemingly sinister Dark Wolf is actually a harbinger of cosmic life.

Is this a painting or a photograph? In this celestial abstract art composed with a cosmic brush, dusty nebula NGC 2170, also known as the Angel Nebula, shines just above the image center. Reflecting the light of nearby hot stars, NGC 2170 is joined by other bluish reflection nebulae, a red emission region, many dark absorption nebulae, and a backdrop of colorful stars. Like the common household items that abstract painters often choose for their subjects, the clouds of gas, dust, and hot stars featured here are also commonly found in a setting like this one -- a massive, star-forming molecular cloud in the constellation of the Unicorn (Monoceros). The giant molecular cloud Mon R2, is impressively close, estimated to be only 2,400 light-years or so away. At that distance, this canvas would be over 60 light-years across. Almost Hyperspace: Random APOD Generator

Spiral galaxy NGC 3169 looks to be unraveling like a ball of cosmic yarn. It lies some 70 million light-years away, south of bright star Regulus toward the faint constellation Sextans. Wound up spiral arms are pulled out into sweeping tidal tails as NGC 3169 (left) and neighboring NGC 3166 interact gravitationally. Eventually the galaxies will merge into one, a common fate even for bright galaxies in the local universe. Drawn out stellar arcs and plumes are clear indications of the ongoing gravitational interactions across the deep and colorful galaxy group photo. The telescopic frame spans about 20 arc minutes or about 400,000 light-years at the group's estimated distance, and includes smaller, bluish NGC 3165 to the right. NGC 3169 is also known to shine across the spectrum from radio to X-rays, harboring an active galactic nucleus that is the site of a supermassive black hole.

Across the center of this spiral galaxy is a bar. And at the center of this bar is smaller spiral. And at the center of that spiral is a supermassive black hole. This all happens in the big, beautiful, barred spiral galaxy cataloged as NGC 1300, a galaxy that lies some 70 million light-years away toward the constellation of the river Eridanus. This Hubble Space Telescope composite view of the gorgeous island universe is one of the most detailed Hubble images ever made of a complete galaxy. NGC 1300 spans over 100,000 light-years and the Hubble image reveals striking details of the galaxy's dominant central bar and majestic spiral arms. How the giant bar formed, how it remains, and how it affects star formation remains an active topic of research. Jigsaw Universe: Astronomy Puzzle of the Day

Like salsa verde on your favorite burrito, a green aurora slathers up the sky in this 2017 June 25 snapshot from the International Space Station. About 400 kilometers (250 miles) above Earth, the orbiting station is itself within the upper realm of the auroral displays. Aurorae have the signature colors of excited molecules and atoms at the low densities found at extreme altitudes. Emission from atomic oxygen dominates this view. The tantalizing glow is green at lower altitudes, but rarer reddish bands extend above the space station's horizon. The orbital scene was captured while passing over a point south and east of Australia, with stars above the horizon at the right belonging to the constellation Canis Major, Orion's big dog. Sirius, alpha star of Canis Major, is the brightest star near the Earth's limb.

Comet R3 PanSTARRS might be best remembered as an Orion comet. A key reason is because Comet C/2025 R3 (PanSTARRS) was near its most spectacular -- in terms of tail visibility -- when passing in front of the iconic constellation. Although rare, other bright comets, too, have ventured across Orion, including Lovejoy in 2015, Hale-Bopp in 1997, and the Great Comet of 1264. Best visible in long duration exposures, the featured image was captured last week from the Craigieburn Mountain Range in New Zealand. Visible in the deep background image are the Orion Nebula, Barnard's Loop, and through R3's tail, the bright star Saiph, the sixth brightest star in the constellation of Orion. Comet R3 PanSTARRS continues to fade as it moves further south, passing into the constellation of the Unicorn (Monoceros) in the next few days. Sky Surprise: What picture did APOD feature on your birthday? (after 1995)

What are some of the most interesting astronomical objects you can see in the night sky? Armed with a good pair of binoculars or a small telescope, if you live in the Northern Hemisphere, you can look for the very popular objects in the Messier Catalog. Most of them, but not all, are also visible from the southern half of the Earth. The featured image shows all 110 objects in the catalog at uniform scale -- the same magnification. Charles Messier created the catalog in the 18th century. He was interested in comets, and his catalog was a list of known comet-like "objects to avoid" in the sky when observing or hunting for comets. The deep sky objects in the catalog include a supernova remnant (the Crab Nebula, M1), other galaxies (such as Andromeda, M31), nebulae (e.g. the Orion Nebula, M42, a star-forming region) and stellar clusters (such as the Pleiades, M45, a bright young open cluster).

The New General Catalog of star clusters and nebulae really isn't so new. In fact, it was published in 1888 - an effort by J. L. E. Dreyer to consolidate the work of astronomers William, Caroline, and John Herschel along with others into a useful single, complete catalog of astronomical discoveries and measurements. Dreyer's work was largely successful and is still important today, as this famous catalog continues to lend its "NGC" to bright clusters, galaxies, and nebulae. Take for example the star cluster known as NGC 188 (item number 188 in the NGC compilation). It lies about 6,000 light-years distant in the northern constellation Cepheus and represents a galactic or open star cluster. With an age of about 7 billion years, NGC 188 is old for an open cluster. Its old, evolved red giant stars have yellowish hues in this colorful, deep sky view. NGC 188 also enjoys the designation Caldwell 1 in a modern compilation of deep sky objects. Located well above the plane of the Milky Way and seen in the direction of planet Earth's north celestial pole, the ancient stellar group is known to some as the Polarissima Cluster.

Today’s composite image features something old, something new, something borrowed, and something blue! Comet R3 PanSTARRS, streaking across the right of the image, likely originated from the Oort Cloud, meaning it is an old Solar System relic from billions of years ago. It’s bright extended ion tail glows blue as the gas escaping the comet’s core is ionized by sunlight. Astronomers are fascinated by comets for all sorts of reasons: comet compositions are untouched time capsules containing the building blocks of Solar System planets; comets may have delivered water to the young Earth; the behavior of cometary tails shed light on solar wind and radiation interactions. The background mosaic, featuring the Orion Nebula (M42), was taken over two nights of observation with the comet captured on the third night. The Orion Nebula is our nearest stellar nursery and, at about 2 million years old, is our something (relatively) new! Now at around 127.5 million kilometers from Earth, we wave goodbye to the borrowed Comet R3 PanSTARRS as it leaves the Solar System. Growing Gallery: Comet R3 in 2026

Orion never had a sword like this. As Comet C/2025 R3 (PanSTARRS) heads out of the inner Solar System, it is putting on quite a show for long exposure cameras. Currently seen toward the constellation of Orion the Hunter, the distant Orion Nebula is visible on the upper right. Comet R3 PanSTARRS is now showing two distinct tails: a short dust tail pointing toward the top of the image and a long and wavy ion tail trailing off toward the upper left. The ion tail points away from the Sun and glows blue from excited carbon monoxide. Large particles in the dust tail somewhat resist the radiation pressure that push them away from the Sun and so retain a bit of the comet's orbit. The dust tail shines by reflected sunlight. The featured image was taken a few days ago from France's Reunion Island in the southern Indian Ocean. Growing Gallery: Comet R3 PanSTARRS in 2026

Many bright nebulae and star clusters in planet Earth's sky are associated with the name of astronomer Charles Messier from his famous 18th century catalog. His name is also given to these two large and remarkable craters on the Moon. Standouts in the dark, smooth lunar Sea of Fertility or Mare Fecunditatis, Messier (left) and Messier A have dimensions of 15 by 8 and 16 by 11 kilometers respectively. Their elongated shapes are explained by the extremely shallow-angle trajectory followed by an impactor, moving left to right, that gouged out the craters. The shallow impact also resulted in two bright rays of material extending along the surface to the right, beyond the picture. Intended to be viewed with red/blue glasses (red for the left eye), this striking stereo picture of the crater pair was recently created from high resolution scans of two images (AS11-42-6304, AS11-42-6305) taken during the Apollo 11 mission to the Moon.

Which way is Comet R3 PanSTARRS going? Not towards the star at the top of the image, because that is Rigel, which, being far in the background, is unrelated to the comet. Not through the nebula in the image middle, because that is the Witch Head Nebula and it, too, is far in the distance -- but not far from Rigel.  Not into northern skies because over the past week Comet C/2025 R3 (PanSTARRS) has moved into southern skies and is now best visible in Earth's Southern Hemisphere toward the west after sunset.  Angularly, Comet R3 PanSTARRS is slowly moving toward the upper right, night by night, and will soon be in the constellation Orion. Spatially, the comet is now headed out of our Solar System but should remain visible to cameras in southern skies for about a week. The featured image was captured last week near Cerro Paranal in Chile. Growing Gallery: Comet R3 PanSTARRS in 2026

What does it mean for Saturn and Neptune to be in retrograde? Featured is a composite of images taken over 34 nights from May 2025 to February 2026 tracing Saturn (brighter, foreground) and Neptune (dimmer, background). Over that time, the two planets exhibited retrograde motion, meaning they appeared to move backward in the sky. This apparent backwards motion occurs when Earth overtakes the slower outer planets as they orbit the Sun. Imagine the Solar System is a running track. Earth "runs" faster along the inside of the track compared to the outer planets. As Earth approaches, aligns, and then "laps" the outer planets, they change position from ahead to behind from the Earth's perspective. This perspective shift is what causes the outer planets to change position in the night sky. An animation corresponding to today’s image shows Saturn and Neptune’s months-long dance across the northern night sky. Saturn stepped from the Pisces constellation into Aquarius and back again while Neptune remained in Pisces. This is the closest Saturn and Neptune have been in the sky since their last conjunction in 1989.

Orion is rarely seen like this. To achieve this majestic vista, you need a camera capable of taking such long duration exposures that faint features in the night sky become revealed. Iconic nebulas that appear include the Orion Nebula, the Flame Nebula, and Barnard's Loop. For contrast, it also helps to have a volcano on the foreground, in this case the Teide volcano on Tenerife on the Canary Islands of Spain. But if you want your Teide volcano snow-covered, you also need good timing -- because that only happens, typically, for a few days each year. Good timing also includes waiting for Orion to appear just behind Teide, which occurred late last year after sunset. The featured image is the result of a series of images taken consecutively with the same camera from the same location. Sky Surprise: What picture did APOD feature on your birthday? (after 1995)

Dust pillars are like interstellar mountains. They survive because they are more dense than their surroundings, but they are slowly being eroded away by a hostile environment. Visible in the featured picture by the Hubble Space Telescope is the end of a huge gas and dust pillar in the Trifid Nebula (M20), punctuated by a smaller pillar pointing up and an unusual jet pointing to the upper left. Many of the bright dots are newly formed stars. A star near the small pillar's end is slowly being stripped of its accreting gas by radiation from a tremendously brighter star situated off the top of the image. The jet extends nearly a light-year and would not be visible without external illumination. As gas and dust evaporate from the pillars, the hidden stellar source of this jet will likely be uncovered, possibly over the next 20,000 years. Explore the Universe: Random APOD Generator

Shrouded in a thick atmosphere, the surface of Saturn's largest moon, Titan, is really hard to see. Small particles suspended in Titan's upper atmosphere cause an almost impenetrable haze, strongly scattering light at visible wavelengths and hiding surface features from prying eyes. Still, Titan's surface is better imaged at infrared wavelengths, where scattering is weaker and atmospheric absorption is reduced. Arrayed around this visible light image (center) of Titan are some of the clearest global infrared views of the tantalizing moon so far. In false color, the six panels present a consistent processing of 13 years of infrared image data from the Visual and Infrared Mapping Spectrometer (VIMS) on board the Cassini spacecraft orbiting Saturn from 2004 to 2017. They offer a stunning comparison with Cassini's visible light view. NASA's revolutionary rotorcraft mission to Titan's surface is due to launch no earlier than July, 2028.

Near the heart of the Virgo Galaxy Cluster, a string of galaxies known as Markarian's Chain stretches across this telescopic field of view. Anchored in the frame at bottom right by prominent lenticular galaxies, M84 (bottom) and M86, you can follow the chain's gentle arc up and toward the left. Near center you'll spot the pair of interacting galaxies NGC 4438 and NGC 4435, known to some as Markarian's Eyes. An estimated 50 million light-years distant, the Virgo Cluster itself is the nearest galaxy cluster. With up to about 2,000 member galaxies, it has a noticeable gravitational influence on our own Local Group of Galaxies. Within the Virgo Cluster at least seven galaxies in Markarian's Chain appear to move coherently, while others may appear to be part of the chain by chance.

No, Earth did not recently acquire six more moons! Today’s APOD is a combination of images following the Moon, Venus, and the Pleiades across a southern Sicilian sky as twilight turned to evening on April 19. From 2023 to 2029, the Pleiades' and the Moon “visit" each other once per month due to the Pleiades' location in the ecliptic plane. April 2026 saw the celestial alignment of their visit with Venus. About six stars in the Pleiades cluster (Messier 45) are typically visible with the unaided eye. Due to the cluster’s visibility across the world, there are many myths and legends across cultures associated with the Pleiades. The Haudenosaunee people of North America, for example, say that seven boys danced so enthusiastically that they lifted off into the sky. Astronomers recently found thousands more Pleiades members, showing that after thousands of years of gazing upon this cluster, there is yet more to learn about the Pleiades.

They're like mountain peaks, but they are forming stars. Bright-rimmed, flowing shapes gather near the center of this rich starfield toward the borders of the nautical southern constellations Puppis and Vela. Composed of interstellar gas and dust, the grouping of light-year sized cometary globules is about 1300 light-years distant. Energetic ultraviolet light from nearby hot stars has molded the globules and ionized their bright rims. The globules also stream away from the Vela supernova remnant which may have influenced their swept-back shapes. Within them, cores of cold gas and dust are likely collapsing to form low mass stars whose formation will ultimately cause the globules to disperse. In fact, cometary globule CG 30 (upper right in the group) sports a small reddish glow inside its head, a telltale sign of energetic jets from a star in the early stages of formation.

Can you find the comet? Somewhere through this web of satellite trails is Comet C/2025 R3 (PanSTARRS), a bright visitor passing through the inner Solar System. Now, the orbiting satellites themselves only appear as streaks because of the long camera exposure, over 10 minutes in this case. On the contrary, to the eye, satellites appear as points that drift slowly across the night sky and shine by reflecting sunlight -- primarily just after sunset and before sunrise. The featured image was taken just before sunrise two weeks ago from Bavaria, Germany. Presently, Comet R3 PanSTARRS is hard to see for even another reason -- because it is so (angularly) close to the Sun. As the comet rounds the Sun, it will be best seen in coming weeks from southern hemispheree skies, although then it will be heading out to interstellar space and fading. If you haven't yet found the comet, don't despair; please take a closer look just above the image center.

Inside the head of this interstellar monster is a star that is slowly destroying it. The huge monster, actually an inanimate series of pillars of gas and dust, measures light years in length. The in-head star is not itself visible through the opaque interstellar dust but is bursting out partly by ejecting opposing beams of energetic particles called Herbig-Haro jets. Located about 7,500 light years away in the Carina Nebula and known informally as Mystic Mountain, the appearance of these pillars is dominated by dark dust even though they are composed mostly of clear hydrogen gas. The featured image was taken with the Hubble Space Telescope. All over these pillars, the energetic light and winds from massive newly formed stars are evaporating and dispersing the dusty stellar nurseries in which they formed. Within a few million years, the head of this giant, as well as most of its body, will have been completely evaporated by internal and surrounding stars.

This seaside sunset offered a surreal experience, captured in a sea and skyscape from the west coast of Sardinia, Italy, planet Earth. The Daliesque scene is a composition of sequential exposures made with a camera and long telephoto lens. The Sun is not melting, though. Its shifting and fluid appearance as it nears the horizon is caused as refraction along the line of sight changes and creates distorted images or mirages of the reddened solar disk. The changes in atmospheric refraction correspond to atmospheric layers with sharply different temperatures and densities. Another famous but fleeting effect of atmospheric refraction produced by a long sight-line to the setting (or rising) Sun is often called the green flash.