Astronomy Picture of the Day

🌌Spin up of a Supermassive Black Hole How fast can a black hole spin? If any object made of regular matter spins too fast -- it breaks apart. But a black hole might not be able to break apart -- and its maximum spin rate is really unknown. Theorists usually model rapidly rotating black holes with the Kerr solution to Einstein's General Theory of Relativity, which predicts several amazing and unu ...

🌌Titan: Moon over Saturn Like Earth's moon, Saturn's largest moon Titan is locked in synchronous rotation with its planet. This mosaic of images recorded by the Cassini spacecraft in May of 2012 shows its anti-Saturn side, the side always facing away from the ringed gas giant. The only moon in the solar system with a dense atmosphere, Titan is the only solar system world besides Earth known to h ...

🌌Young Star Cluster NGC 346 The most massive young star cluster in the Small Magellanic Cloud is NGC 346, embedded in our small satellite galaxy's largest star forming region some 210,000 light-years distant. Of course the massive stars of NGC 346 are short lived, but very energetic. Their winds and radiation sculpt the edges of the region's dusty molecular cloud triggering star-formation within ...

🌌MESSENGER's Last Day on Mercury The first to orbit inner planet Mercury, the MESSENGER spacecraft came to rest on this region of Mercury's surface on April 30, 2015. Constructed from MESSENGER image and laser altimeter data, the projected scene looks north over the northeastern rim of the broad, lava filled Shakespeare basin. The large, 48 kilometer (30 mile) wide crater Janacek is near the upp ...

© Daniel Korona

🌌A Happy Sky over Bufa Hill in Mexico Sometimes, the sky itself seems to smile. A few days ago, visible over much of the world, an unusual superposition of our Moon with the planets Venus and Saturn created just such an iconic facial expression. Specifically, a crescent Moon appeared to make a happy face on the night sky when paired with seemingly nearby planets. Pictured is the scene as it appe ...

© Natan Fontes

🌌Saturn's Rings Appear to Disappear Where are Saturn's ears? Galileo is credited, in 1610, as the first person to see Saturn's rings. Testing out Lipperhey's recently co-invented telescope, Galileo did not know what they were and so called them "ears". The mystery deepened in 1612, when Saturn's ears mysteriously disappeared. Today we know exactly what happened: from the perspective of the Earth ...

© Francis Bozon & Cecil Navick (AstroA. R. O.)

🌌Gum 37 and the Southern Tadpoles This cosmic skyscape features glowing gas and dark dust clouds alongside the young stars of NGC 3572. A beautiful emission nebula and star cluster, it sails far southern skies within the nautical constellation Carina. Stars from NGC 3572 are toward top center in the telescopic frame that would measure about 100 light-years across at the cluster's estimated dista ...

🌌IC 418: The Spirograph Nebula What is creating the strange texture of IC 418? Dubbed the Spirograph Nebula for its resemblance to drawings from a cyclical drawing tool, planetary nebula IC 418 shows patterns that are not well understood. Perhaps they are related to chaotic winds from the variable central star, which changes brightness unpredictably in just a few hours. By contrast, evidence ind ...

🌌Barred Spiral Galaxy NGC 5335 This stunning portrait of NGC 5335 was captured by the Hubble Space Telescope. Some 170,000 light-years across and over 200 million light-years away toward the constellation Virgo, the magnificent spiral galaxy is seen face-on in Hubble's view. Within the galactic disk, loose streamers of star forming regions lie along the galaxy's flocculent spiral arms. But the m ...

🌌Asteroid Donaldjohanson Main belt asteroid 52246 Donaldjohanson is about 8 kilometers long and 3.5 kilometers across. On April 20, this sharp close-up of the asteroid was captured at a distance of about 1100 kilometers by the Lucy spacecraft's long range camera during its second asteroid encounter. Named after American paleoanthropologist Donald Johanson, discoverer of the Lucy hominid fossil, ...

© Daniel Stern

🌌NGC 6164: A Dragon's Egg Beautiful emission nebula NGC 6164 was created by a rare, hot, luminous O-type star, some 40 times as massive as the Sun. Seen at the center of the cosmic cloud, the star is a mere 3 to 4 million years old. In another three to four million years the massive star will end its life in a supernova explosion. Spanning around 4 light-years, the nebula itself has a bipolar sy ...

© Koen van Barneveld

🌌An Almost Everything Sky This surprising sky has almost everything. First, slanting down from the upper left and far in the distance is the central band of our Milky Way Galaxy. More modestly, slanting down from the upper right and high in Earth's atmosphere is a bright meteor. The dim band of light across the central diagonal is zodiacal light: sunlight reflected from dust in the inner Solar S ...

© Rich Addis

🌌Terminator Moon: A Moonscape of Shadows What's different about this Moon? It's the terminators. In the featured image, you can't directly see any terminator -- the line that divides the light of day from the dark of night. That's because the featured image is a digital composite of many near-terminator lunar strips over a full Moon. Terminator regions show the longest and most prominent shadows ...

🌌Galaxy Lenses Galaxy from Webb Is this one galaxy or two? Although it looks like one, the answer is two. One path to this happening is when a small galaxy collides with a larger galaxy and ends up in the center. But in the featured image, something more rare is going on. Here, the central light-colored elliptical galaxy is much closer than the blue and red-colored spiral galaxy that surrounds i ...

© Infrared: NASA, Spitzer Space Telescope; Visible: Oliver Czernetz, Siding Spring Obs.

🌌The Orion Nebula in Visible and Infrared The Great Nebula in Orion is a colorful place. Visible to the unaided eye, it appears as a small fuzzy patch in the constellation of Orion. Long exposure, multi-wavelength images like this, however, show the Orion Nebula to be a busy neighborhood of young stars, hot gas, and dark dust. This digital composite features not only three colors of visible ligh ...

🌌Painting with Jupiter In digital brush strokes, Jupiter's signature atmospheric bands and vortices were used to form this interplanetary post-impressionist work of art. The creative image from citizen scientist Rick Lundh uses data from the Juno spacecraft's JunoCam. To paint on the digital canvas, a JunoCam image with contrasting light and dark tones was chosen for processing and an oil-painti ...

© Dan Bartlett

🌌Comet C/2025 F2 SWAN In late March, the comet now designated C/2025 F2 SWAN was found independently by citizen scientists Vladimir Bezugly, Michael Mattiazzo, and Rob Matson while examining publicly available image data from the Solar Wind ANisotropies (SWAN) camera on the sun-staring SOHO spacecraft. Comet SWAN's coma, its greenish color a signature of diatomic carbon molecules fluorescing in ...

© Daniel Adibi

🌌Virgo Cluster Galaxies Galaxies of the Virgo Cluster are scattered across this nearly 4 degree wide telescopic field of view. About 50 million light-years distant, the Virgo Cluster is the closest large galaxy cluster to our own local galaxy group. Prominent here are Virgo's bright elliptical galaxies from the Messier catalog, M87 at bottom left, and M86 and M84 near center right. M86 and M84 a ...

© Taavi Niittee (Tõrva Astronomy Club)

🌌Halo of the Cat's Eye What created the unusual halo around the Cat's Eye Nebula? No one is sure. What is sure is that the Cat's Eye Nebula (NGC 6543) is one of the best known planetary nebulae on the sky. Although haunting symmetries are seen in the bright central region, this image was taken to feature its intricately structured outer halo, which spans over three light-years across. Planetary ...

🌌Planetary Nebula NGC 1514 from Webb What happens when a star runs out of nuclear fuel? For stars like our Sun, the center condenses into a white dwarf while the outer atmosphere is expelled into space to appear as a planetary nebula. The expelled outer atmosphere of planetary nebula NGC 1514 appears to be a jumble of bubbles -- when seen in visible light. But the view from the James Webb Space ...

🌌The Galactic Center in Radio from MeerKAT What's happening at the center of our galaxy? It's hard to tell with optical telescopes since visible light is blocked by intervening interstellar dust. In other bands of light, though, such as radio, the galactic center can be imaged and shows itself to be quite an interesting and active place. The featured picture shows an image of our Milky Way's cen ...

🌌An Unusual Hole in Mars What created this unusual hole in Mars? Actually, there are numerous holes pictured in this Swiss cheese-like landscape, with all-but-one of them showing a dusty, dark, Martian terrain beneath evaporating, light, carbon dioxide ice. The most unusual hole is on the upper right, spans about 100 meters, and seems to punch through to a lower level. Why this hole exists and w ...

© Jordi Coy

🌌Moon Near the Edge Most of us watch the Moon at night. But the Moon spends nearly as many daylight hours above our horizon, though in bright daytime skies the lunar disk looks pale and can be a little harder to see. Of course in daytime skies the Moon also appears to cycle through its phases, shining by reflected sunlight as it orbits our fair planet. For daytime moonwatchers, the Moon is proba ...

© A.J. Smadi

🌌The ISS Meets Venus Made with a telescope shaded from bright sunlight by an umbrella, on April 5 a well-planned video captured a crescent Venus shining in clear daytime skies from Shoreline, Washington, USA at 11:57AM Pacific Time. It also caught the International Space Station in this single video frame. In close conjunction with the bright planet, the faint outline of the orbital outpost seen ...

© Daniel Yang K.

🌌38 Hours with the M81 Group From a garden on planet Earth, 38 hours of exposure with a camera and small telescope produced this cosmic photo of the M81 galaxy group. In fact, the group's dominant galaxy M81 is near the center of the frame sporting grand spiral arms and a bright yellow core. Also known as Bode's galaxy, M81 itself spans some 100,000 light-years. Near the top is cigar-shaped irre ...