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.
Sunset at the Spiral Jetty
In dwindling twilight at an August day's end, these broad dark bands appeared in the sky for a moment, seen from Robert Smithson's Spiral Jetty on the eastern shore of Utah's…
M33: Triangulum Galaxy
The small, northern constellation Triangulum harbors this magnificent face-on spiral galaxy, M33. Its popular names include the Pinwheel Galaxy or just the Triangulum Galaxy . M33…
Hartley 2 Star Cluster Tour
Early in November, small but active Comet Hartley 2 (103/P Hartley) became the fifth comet imaged close-up by a spacecraft from planet Earth . Continuing its own tour of the solar…
Martian Moon Phobos from Mars Express
Why is Phobos so dark? Phobos , the largest and innermost of two Martian moons, is the darkest moon in the entire Solar System . Its unusual orbit and color indicate that it may…
A Supercell Thunderstorm Cloud Over Montana
Is that a spaceship or a cloud? Although it may seem like an alien mothership , it's actually a impressive thunderstorm cloud called a supercell . Such colossal storm systems…
Dark Belt Reappearing on Jupiter
Why are planet-circling clouds disappearing and reappearing on Jupiter? Although the ultimate cause remains unknown, planetary meteorologists are beginning to better understand…
Anticrepuscular Rays Over Colorado
What's happening over the horizon? Although the scene may appear somehow supernatural , nothing more unusual is occurring than a setting Sun and some well placed clouds. Pictured…
Star Streams of NGC 4216
Some 40 million light-years distant, edge-on spiral galaxy NGC 4216 is nearly 100,000 light-years across, about the size of our own Milky Way . Found in the dense Virgo Galaxy…
Flame Nebula Close-Up
Of course, the Flame Nebula is not on fire. Also known as NGC 2024 , the nebula's suggestive reddish color is due to the glow of hydrogen atoms at the edge of the giant Orion…
Stardust in Aries
This composition in stardust covers almost 2 degrees on the sky, close to the border of the zodiacal constellation Aries and the plane of our Milky Way Galaxy. At the lower right…
Flowing Auroras Over Norway
Have you ever seen an aurora? Auroras are occurring again with increasing frequency. With the Sun being unusually dormant over the past three years, the amount of Sun-induced…
Gas and Snow Jets from Comet Hartley 2
Unusual jets have been discovered emanating from Comet Hartley 2. The EPOXI spacecraft imaged the jets in unprecedented detail during its flyby of the comet earlier this month.…
A Dark Dune Field in Proctor Crater on Mars
Was this image taken with a telescope or a microscope? Perhaps this clue will help: if the dark forms were bacteria , they would each span over football field across. What is…
A Massive Star in NGC 6357
For reasons unknown, NGC 6357 is forming some of the most massive stars ever discovered. One such massive star, near the center of NGC 6357 , is framed above carving out its own…
Stephan's Quintet
The first identified compact galaxy group, Stephan's Quintet is featured in this eye-catching image constructed with data drawn from the extensive Hubble Legacy Archive . About…
Nebulae in the Northern Cross
Explore a beautiful and complex region of nebulae strewn along the plane of our Milky Way Galaxy in this widefield skyscape. The image emphasizes cosmic gas clouds in a 25 by 25…
Sisters of the Dusty Sky
Hurtling through a cosmic dust cloud some 400 light-years away, the lovely Pleiades or Seven Sisters star cluster is well-known for its striking blue reflection nebulae . In the…
Frosted Leaf Orion
Sometimes, you can put some night sky in your art. Captured above Japan earlier this month, a picturesque night sky was photographed behind a picturesque frosted leaf. The…
Atoms-for-Peace Galaxy Collision
Is this what will become of our Milky Way Galaxy? Perhaps if we collide with the Andromeda Galaxy in a few billion years, it might. Pictured above is NGC 7252, a jumble of stars…
Home from Above
There's no place like home . Peering out of the windows of the International Space Station (ISS), astronaut Tracy Caldwell Dyson takes in the planet on which we were all born, and…
Multiverses: Do Other Universes Exist?
Do nearly exact copies of you exist in other universes? If one or more of the multiverse hypotheses is correct, then quite possibly they do. In the above computer-enhanced…
Spiral Galaxy M66
Big beautiful spiral galaxy M66 lies a mere 35 million light-years away. About 100 thousand light-years across, the gorgeous island universe is well known to astronomers as a…
NGC 7023: The Iris Nebula
Like delicate cosmic petals, these clouds of interstellar dust and gas have blossomed 1,300 light-years away in the fertile star fields of the constellation Cepheus . Sometimes…
Two Views, Two Crescents
Venus rose in a glowing dawn sky on November 5th, just before the Sun. For early morning risers, its brilliant crescent phase was best appreciated with binoculars or a small…
Viewing discoveries from 4 December 2010 through 11 November 2010.