Astronomy Picture of the Day

🌌Spiral Aurora over Iceland The scene may look like a fantasy, but it's really Iceland. The rock arch is named Gatklettur and located on the island's northwest coast. Some of the larger rocks in the foreground span a meter across. The fog over the rocks is really moving waves averaged over long exposures. The featured image is a composite of several foreground and background shots taken with the ...

© Matthew Dieterich

🌌NGC 2264: The Cone Nebula Stars are forming in the gigantic dust pillar called the Cone Nebula. Cones, pillars, and majestic flowing shapes abound in stellar nurseries where clouds of gas and dust are sculpted by energetic winds from newborn stars. The Cone Nebula, a well-known example, lies within the bright galactic star-forming region NGC 2264. The featured image of the Cone was captured rec ...

© Jose Francisco Hernández

🌌Tails of Comet ZTF Comet ZTF may become visible to the unaided eye. Discovered early last year, this massive snowball has been brightening as it approaches the Sun and the Earth. C/2022 E3 (ZTF) will be closest to the Sun later this week, at which time it may become visible even without binoculars to northern observers with a clear and dark sky. As they near the Sun, comet brightnesses are noto ...

🌌Where Your Elements Came From The hydrogen in your body, present in every molecule of water, came from the Big Bang. There are no other appreciable sources of hydrogen in the universe. The carbon in your body was made by nuclear fusion in the interior of stars, as was the oxygen. Much of the iron in your body was made during supernovas of stars that occurred long ago and far away. The gold in y ...

© Zarcos Palma

🌌Space Stations in Low Earth Orbit On January 3, two space stations already illuminated by sunlight in low Earth orbit crossed this dark predawn sky. Moving west to east (left to right) across the composited timelapse image China's Tiangong Space Station traced the upper trail captured more than an hour before the local sunrise. Seen against a starry background Tiangong passes just below the inv ...

© Niveth Kumar

🌌Moon O'Clock 2022 The first Full Moon of 2023 is in the sky tonight opposite the Sun at 23:08 UTC. Big and beautiful, the Moon at its brightest phase should be easy to spot. Still, for quick reference images captured near the times of all the full moons of 2022 are aranged in this dedicated astro-imaging project from Sri Lanka, planet Earth. The day, month, and a traditional popular name for 20 ...

© Stefan Thrun

🌌Messier 45: The Daughters of Atlas and Pleione Hurtling through a cosmic dust cloud a mere 400 light-years away, the lovely Pleiades or Seven Sisters open star cluster is well-known for its striking blue reflection nebulae. It lies in the night sky toward the constellation Taurus and the Orion Arm of our Milky Way galaxy. The sister stars are not related to the dusty cloud though. They just hap ...

© Mike Selby

🌌CG4: The Globule and the Galaxy Can a gas cloud eat a galaxy? It's not even close. The "claw" of this odd looking "creature" in the featured photo is a gas cloud known as a cometary globule. This globule, however, has ruptured. Cometary globules are typically characterized by dusty heads and elongated tails. These features cause cometary globules to have visual similarities to comets, but in re ...

© Tommy Lease

🌌Kemble’s Cascade of Stars This line of stars is real. A little too faint to see with the unaided eye, Kemble’s Cascade of stars inspires awe when seen with binoculars. Like the Big Dipper though, Kemble’s Cascade is an asterism, not a constellation. The asterism is visible in the northern sky toward the long-necked constellation of the Giraffe (Camelopardalis). This string of about 20 unrelated ...

© Tunc Tezel

🌌After Sunset Planet Parade Look up tonight and see a whole bunch of planets. Just after sunset, looking west, planets Venus, Saturn, Jupiter and Mars will all be simultaneously visible. Listed west to east, this planetary lineup will have Venus nearest the horizon, but setting shortly after the Sun. It doesn't matter where on Earth you live because this early evening planet parade will be visib ...

🌌The Largest Rock in our Solar System There, that dot on the right, that's the largest rock known in our Solar System. It is larger than every known asteroid, moon, and comet nucleus. It is larger than any other local rocky planet. This rock is so large its gravity makes it into a large ball that holds heavy gases near its surface. (It used to be the largest known rock of any type until the rece ...

🌌Moon over Makemake Makemake (sounds like MAH-kay MAH-kay), second brightest dwarf planet of the Kuiper belt, has a moon. Nicknamed MK2, Makemake's moon reflects sunlight with a charcoal-dark surface, about 1,300 times fainter than its parent body. Still, in 2016 it was spotted in Hubble Space Telescope observations intended to search for faint companions with the same technique used to find the ...

© Gabor Balazs

🌌Mars and the Star Clusters At this year's end Mars still shines brightly in planet Earth's night as it wanders through the head-strong constellation Taurus. Its bright yellowish hue dominates this starry field of view that includes Taurus' alpha star Aldebaran and the Hyades and Pleiades star clusters. While red giant Aldebaran appears to anchor the V-shape of the Hyades at the left of the fram ...

© Jason Close

🌌Horsehead and Flame The Horsehead Nebula, famous celestial dark marking also known as Barnard 33, is notched against a background glow of emission nebulae in this sharp cosmic skyscape. About five light-years "tall" the Horsehead lies some 1,500 light-years away in the constellation of Orion. Within the region's fertile molecular cloud complex, the expanse of obscuring dust has a recognizable s ...

© Adam Block

🌌Messier 88 Charles Messier described the 88th entry in his 18th century catalog of Nebulae and Star Clusters as a spiral nebula without stars. Of course the gorgeous M88 is now understood to be a galaxy full of stars, gas, and dust, not unlike our own Milky Way. In fact, M88 is one of the brightest galaxies in the Virgo Galaxy Cluster some 50 million light-years away. M88's beautiful spiral arm ...

© Lukas Moesch

🌌A Full Circle Rainbow over Norway Have you ever seen an entire rainbow? From the ground, typically, only the top portion of a rainbow is visible because directions toward the ground have fewer raindrops. From the air, though, the entire 360-degree circle of a rainbow is more commonly visible. Pictured here, a full-circle rainbow was captured over the Lofoten Islands of Norway in September by a ...

© Russell Croman

🌌NGC 6164: Dragon's Egg Nebula and Halo The star at the center created everything. Known as the Dragon's Egg, this star -- a rare, hot, luminous O-type star some 40 times as massive as the Sun -- created not only the complex nebula (NGC 6164) that immediately surrounds it, but also the encompassing blue halo. Its name is derived, in part, from the region's proximity to the picturesque NGC 6188, ...

© Chuck Derus

🌌Geminids and the Mittens Asteroid 3200 Phaethon's annual gift to planet Earth always arrives in December. Otherwise known as the Geminid meteor shower, the source of the meteroid stream is dust shed along the orbit of the mysterious asteroid. Near the December 13/14 peak of the shower's activity, geminid meteors are captured in this night skyscape, composited from 22 images of starry sky taken ...

© Dan Bartlett

🌌Comet 2022 E3 (ZTF) Comet C/2022 E3 (ZTF) was discovered by astronomers using the wide-field survey camera at the Zwicky Transient Facility this year in early March. Since then the new long-period comet has brightened substantially and is now sweeping across the northern constellation Corona Borealis in predawn skies. It's still too dim to see without a telescope though. But this fine telescopi ...

🌌Cassini Looks Out from Saturn This is what Saturn looks like from inside the rings. In 2017, for the first time, NASA directed the Cassini spacecraft to swoop between Saturn and its rings. During the dive, the robotic spacecraft took hundreds of images showing unprecedented detail for structures in Saturn's atmosphere. Looking back out, however, the spacecraft was also able to capture impressiv ...

© Martin Pugh

🌌NGC 1365: Majestic Island Universe Barred spiral galaxy NGC 1365 is truly a majestic island universe some 200,000 light-years across. Located a mere 60 million light-years away toward the faint but heated constellation Fornax, NGC 1365 is a dominant member of the well-studied Fornax Cluster of galaxies. This impressively sharp color image shows the intense, reddish star forming regions near the ...

© Goran Strand

🌌Sun Halo at Sixty-three Degrees North Happy Solstice! Today is the December solstice, marking an astronomical beginning of summer in the southern hemisphere and winter in the north. On its yearly trek through planet Earth's skies, at this solstice the Sun reaches its southern most declination, 23.5 degrees south, at 21:48 UTC. About 4 days ago the Sun was near this seasonal southern limit and s ...

© Hannah Rochford

🌌Thor's Helmet 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 with a fast wind from the bright, massive star near t ...

© Craig Stocks

🌌The Tadpole Nebula in Gas and Dust What's causing the commotion in the Tadpole Nebula? Star formation. Dusty emission in the Tadpole Nebula, IC 410, lies about 12,000 light-years away in the northern constellation of the Charioteer (Auriga). The cloud of glowing gas is over 100 light-years across, sculpted by stellar winds and radiation from embedded open star cluster NGC 1893. Formed in the in ...

© Tragoolchitr Jittasaiyapan

🌌25 Brightest Stars in the Night Sky Do you know the names of some of the brightest stars? It's likely that you do, even though some bright stars have names so old they date back to near the beginning of written language. Many world cultures have their own names for the brightest stars, and it is culturally and historically important to remember them. In the interest of clear global communicatio ...