Browse NASA Astronomy Picture of the Day archive by date and media: Archive Discoveries
Browse the NASA APOD archive without needing the exact date first. Filter by media type and keep moving deeper into older images and videos.

Galaxy Wars: M81 versus M82
On the right, surrounded by blue spiral arms, is spiral galaxy M81 . On the left, marked by red gas and dust clouds, is irregular galaxy M82 . This stunning vista shows these two…

Reinvigorated Sun and Prominence
Dramatic prominences can sometimes be seen looming just beyond the edge of the sun. Such was the case last week as a giant prominence, visible above on the right, highlighted a…

The Nearby Milky Way in Cold Dust
What shapes the remarkable dust tapestry of the nearby Milky Way Galaxy? No one knows for sure. The intricate structures, shown above , were resolved in new detail recently in a…

Equinox + 1
Twice a year, at the Spring and Fall equinox , the Sun rises due east. In an emphatic demonstration of this celestial alignment , photographer Joe Orman recorded this inspiring…

Zodiacal Light Vs. Milky Way
Ghostly Zodiacal light, featured near the center of this remarkable panorama, is produced as sunlight is scattered by dust in the Solar System's ecliptic plane . In the weeks…

The Seagull and the Duck
Seen as a seagull and a duck, these nebulae are not the only cosmic clouds to evoke images of flight. But both are winging their way across this broad celestial landscape,…

Fermi Catalogs the Gamma-ray Sky
What shines in the gamma-ray sky? The most complete answer yet to that question is offered by the Fermi Gamma-ray Space Telescope's first all-sky catalog . Fermi's sources of…

Phobos from Mars Express
Why is this small object orbiting Mars? The origin of Phobos , the larger of the two moons orbiting Mars, remains unknown. Phobos and Deimos appear very similar to C-type…

Detailed View of a Solar Eclipse Corona
Only in the fleeting darkness of a total solar eclipse is the light of the solar corona easily visible. Normally overwhelmed by the bright solar disk, the expansive corona , the…

Illuminated Cloud Trails Above Greece
It may appear to be day, but it's night. Those wondrous orange streaks may appear to be rays from the setting Sun, but they're actually thin clouds illuminated by the Moon as they…

Binary Black Hole in 3C 75
What's happening in the middle of this massive galaxy? There, two bright sources at the center of this composite x-ray (blue)/ radio (pink) image are thought to be co-orbiting…

Centaurus A
Only 11 million light-years away, Centaurus A is the closest active galaxy to planet Earth. Spanning over 60,000 light-years, the peculiar elliptical galaxy, also known as NGC…

JWST: Mirrors and Masked Men
Who are these masked men? Technicians from Ball Aerospace and NASA at Marshall Space Flight Center's X-ray and Cryogenic Facility, of course, testing primary mirror segments of…

Yukon Aurora with Star Trails
Fixed to a tripod, a camera can record graceful trails traced by stars as planet Earth rotates on its axis. But at high latitudes during March and April, it can also capture an…

Saturn's Moon Helene from Cassini
What's happening on the surface of Saturn's moon Helene? The moon was imaged in unprecedented detail last week as the robotic Cassini spacecraft orbiting Saturn swooped to within…

Galaxies Beyond the Heart: Maffei 1 and 2
The two galaxies on the far left were unknown until 1968. Although they would have appeared as two of the brighter galaxies on the night sky, the opaque dust of the central band…

Mars Over the Allalinhorn
What's that bright object in the sky? A common question with answers that vary by time and season , the quick answer just after sunset in middle of last month, from the northern…

Spirit Rover at Engineering Flats on Mars
Is it art? If so, the paintbrush was the Spirit robotic rover , the canvas was the soil on Mars , and the artists were the scientists and engineers of the Mars Exploration Rover…

Pillar at Sunset
Reddened light from the setting Sun illuminates the cloud banks hugging this snowy, rugged terrain. Inspiring a moment of quiet contemplation, the sunset scene included a…

Deep Auriga
The plane of our Milky Way Galaxy runs right through Auriga , the Charioteer . A good part of the ancient northern constellation's rich collection of nebulae and star clusters is…

NGC 4565: Galaxy on Edge
Magnificent spiral galaxy NGC 4565 is viewed edge-on from planet Earth. Also known as the Needle Galaxy for its narrow profile, bright NGC 4565 is a stop on many telescopic tours…

The International Space Station from Above
The International Space Station (ISS) is the largest human-made object ever to orbit the Earth . The ISS is so large that it can be seen drifting overhead with the unaided eye ,…

M78 and Reflecting Dust Clouds in Orion
An eerie blue glow and ominous columns of dark dust highlight M78 and other bright reflection nebula in the constellation of Orion . The dark filamentary dust not only absorbs…

Slope Streaks in Acheron Fossae on Mars
What creates these picturesque dark streaks on Mars? No one knows for sure. A leading hypothesis is that streaks like these are caused by fine grained sand sliding down the banks…
Viewing discoveries from 24 March 2010 through 1 March 2010.