Astronomy Picture of the Day

🌌Enceladus in True Color Do oceans under the ice of Saturn's moon Enceladus contain life? A reason to think so involves long features -- some dubbed tiger stripes -- that are known to be spewing ice from the moon's icy interior into space. These surface cracks create clouds of fine ice particles over the moon's South Pole and create Saturn's mysterious E-ring. Evidence for this has come from the ...

🌌Between Scylla and Charybdis: A Double Cosmic Discovery Can you identify this celestial object? Likely not — because this is a discovery image. Massive stars forge heavy elements in their cores and, after a few million years, end their lives in powerful supernova explosions. These remnants cool relatively quickly and fade, making them difficult to detect. To uncover such faint, previously unkno ...

🌌Facing NGC 3344 From our vantage point in the Milky Way Galaxy, we see NGC 3344 face-on. Nearly 40,000 light-years across, the big, beautiful spiral galaxy is located just 20 million light-years away in the constellation of Leo Minor. This multi-color Hubble Space Telescope close-up of NGC 3344 includes remarkable details from near infrared to ultraviolet wavelengths. The frame extends some 15, ...

🌌Perseverance Selfie with Ingenuity On the Mars rover's mission Sol 46 or Earth date April 6, 2021, Perseverance held out a robotic arm to take its first selfie on Mars. The WATSON camera at the end of the arm was designed to take close-ups of Martian rocks and surface details though, and not a quick snap shot of friends and smiling faces. In the end, teamwork and weeks of planning on Mars time ...

© Mike Selby

🌌NGC 6302: The Butterfly Nebula The bright clusters and nebulae of planet Earth's night sky are often given the names of flowers or insects, and its whopping 3 light-year wingspan, NGC 6302 is no exception. With an estimated surface temperature of about 250,000 degrees C, the central star of the planetary nebula is transforming into a white dwarf star, becoming exceptionally hot, and shining bri ...

© Branko Nadj

🌌Savudrija Star Trails Savudrija lighthouse shines along the coast near the northern end of the Istrian peninsula in this well-composed night skyscape. A navigational aid for sailors on the Adriatic Sea, the historic lighthouse was constructed in the early 19th century. But an even older aid to navigation shines in the sky above, Polaris, alpha star of the constellation Ursa Minor and also known ...

🌌A Milky Road to the Rubin Observatory Is the sky the same every night? No -- the night sky changes every night in many ways. To better explore how the night sky changes, the USA's NSF and DOE commissioned the Vera C. Rubin Observatory in Cerro Pachón, Chile. In final testing before routine operations, Rubin will begin to explore these nightly changes -- slight differences that can tell us much ...

© Miguel Claro (TWAN); Rollover Annotation: Judy Schmidt

🌌Rainbow Airglow over the Azores Why would the sky glow like a giant repeating rainbow? Airglow. Now, air glows all of the time, but it is usually hard to see. A disturbance however -- like an approaching storm -- may cause noticeable rippling in the Earth's atmosphere. These gravity waves are oscillations in air analogous to those created when a rock is thrown in calm water. The long-duration e ...

© Abdullah Alharbi

🌌Veil Nebula: Wisps of an Ancient Supernova Wisps like this are all that remain visible of a Milky Way star. About 7,000 years ago that star exploded in a supernova, leaving the Veil Nebula. At the time, the expanding cloud was likely as bright as a crescent Moon, remaining visible for weeks to people living at the dawn of recorded history. Today, the resulting supernova remnant, also known as t ...

© Domingo Pestana

🌌UGC 1810: Wildly Interacting Galaxy from Hubble What's happening to this spiral galaxy? Although details remain uncertain, it surely has to do with an ongoing battle with its smaller galactic neighbor. The featured galaxy is labelled UGC 1810 by itself, but together with its collisional partner is known as Arp 273. The overall shape of UGC 1810 -- in particular its blue outer ring -- is likely ...

© Marcella Giulia Pace

🌌Afterimage Sunset On May 7, the Sun setting behind a church bell tower was captured in this filtered and manipulated digital skyscape from Ragusa, Sicily, planet Earth. In this version of the image the colors look bizarre. Still, an intriguing optical illusion known as an afterimage can help you experience the same scene with a more natural looking appearance. To try it, find the sunspots of ac ...

© Tunc Tezel

🌌Mars in the Loop This composite of images spaced a weather-permitting 5 to 9 days apart, from 2024 September 19 (top right) through 2025 May 18 (bottom left), faithfully traces ruddy-colored Mars as it makes a clockwise loop through the constellations Gemini and Cancer in planet Earth's night sky. You can connect the dots and dates with your cursor over the image, but be sure to check out this ...

© Franz Hofmann

🌌Irregular Dwarf Galaxy Sextans A Grand spiral galaxies often seem to get all the attention, flaunting young, bright, blue star clusters and pinkish star forming regions along graceful, symmetric spiral arms. But small galaxies form stars too, like irregular dwarf galaxy Sextans A. Its young star clusters and star forming regions are gathered into a gumdrop-shaped region a mere 5,000 light-years ...

🌌Herbig-Haro 24 This might look like a double-bladed lightsaber, but these two cosmic jets actually beam outward from a newborn star in a galaxy near you. Constructed from Hubble Space Telescope image data, the stunning scene spans about half a light-year across Herbig-Haro 24 (HH 24), some 1,300 light-years or 400 parsecs away in the stellar nurseries of the Orion B molecular cloud complex. Hid ...

© Ireneusz Nowak

🌌Zeta and Rho Ophiuchi with Milky Way Behold one of the most photogenic regions of the night sky, captured impressively. Featured, the band of our Milky Way Galaxy runs diagonally along the bottom-left corner, while the colorful Rho Ophiuchi cloud complex is visible just right of center and the large red circular Zeta Ophiuchi Nebula appears near the top. In general, red emanates from nebulas gl ...

🌌Spiral Galaxy NGC 2566 from Webb What’s happening in the center of spiral galaxy NGC 2566? First, the eight rays that appear to be coming out of the center in the featured infrared image are not real — they are diffraction spikes caused by the mechanical structure of the Webb space telescope itself. The center of NGC 2566 is bright but not considered unusual, which means that it likely contains ...

© NASA, Juno, SwRI, MSSS; Processing & License: Gerald Eichstädt & Seán Doran

🌌Beneath Jupiter Jupiter is stranger than we knew. NASA's Juno spacecraft has now completed over 70 swoops past Jupiter as it moves around its highly elliptical orbit. Pictured from 2017, Jupiter is seen from below where, surprisingly, the horizontal bands that cover most of the planet disappear into swirls and complex patterns. A line of white oval clouds is visible nearer to the equator. Impre ...

🌌Deimos Before Sunrise Deimos takes 30 hours and 18 minutes to complete one orbit around the Red Planet. That's a little more than one Martian day or sol which is about 24 hours and 40 minutes long, so Deimos drifts westward across the Martian sky. About 15 kilometers across at its widest, the smallest of Mars' two moons is bright though. In fact Deimos is the brightest celestial object in this ...

© Massimo Di Fusco

🌌NGC 6366 vs 47 Ophiuchi Most globular star clusters roam the halo of our Milky Way galaxy, but globular cluster NGC 6366 lies close to the galactic plane. About 12,000 light-years away toward the constellation Ophiuchus, the cluster's starlight is dimmed and reddened by the Milky Way's interstellar dust when viewed from planet Earth. As a result, the stars of NGC 6366 look almost golden in this ...

© Alberto Pisabarro

🌌Curly Spiral Galaxy M63 A bright spiral galaxy of the northern sky, Messier 63 is nearby, about 30 million light-years distant toward the loyal constellation Canes Venatici. Also cataloged as NGC 5055, the majestic island universe is nearly 100,000 light-years across, about the size of our own Milky Way. Its bright core and majestic spiral arms lend the galaxy its popular name, The Sunflower Ga ...

© Pau Montplet Sanz

🌌International Space Station Crosses the Sun Typically, the International Space Station is visible only at night. Slowly drifting across the night sky as it orbits the Earth, the International Space Station (ISS) can be seen as a bright spot about once a month from many locations. The ISS is then visible only just after sunset or just before sunrise because it shines by reflected sunlight -- onc ...

© Marzena Rogozinska

🌌Milky Way over Maunakea Have you ever seen the band of our Milky Way Galaxy? In a clear sky from a dark location at the right time, a faint band of light becomes visible across the sky. Soon after your eyes become dark adapted, you might spot the band for the first time. It may then become obvious. Then spectacular. One reason for your growing astonishment might be the realization that this fuz ...

🌌Ares 3 Landing Site: The Martian Revisited This close-up from the Mars Reconnaissance Orbiter's HiRISE camera shows weathered craters and windblown deposits in southern Acidalia Planitia. A striking shade of blue in standard HiRISE image colors, to the human eye the area would probably look grey or a little reddish. But human eyes have not gazed across this terrain, unless you count the eyes of ...

🌌Messier 101 Big, beautiful spiral galaxy M101 is one of the last entries in Charles Messier's famous catalog, but definitely not one of the least. About 170,000 light-years across, this galaxy is enormous, almost twice the size of our own Milky Way. M101 was also one of the original spiral nebulae observed by Lord Rosse's large 19th century telescope, the Leviathan of Parsontown. Assembled from ...

🌌A Plutonian Landscape This shadowy landscape of majestic mountains and icy plains stretches toward the horizon on a small, distant world. It was captured from a range of about 18,000 kilometers when New Horizons looked back toward Pluto, 15 minutes after the spacecraft's closest approach on July 14, 2015. The dramatic, low-angle, near-twilight scene follows rugged mountains formally known as No ...