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.
M45: The Pleiades Star Cluster
Have you ever seen the Pleiades star cluster? Even if you have, you probably have never seen it as dusty as this. Perhaps the most famous star cluster on the sky, the bright stars…
APOD is 20 Years Old Today
Welcome to the vicennial year of the Astronomy Picture of the Day! Perhaps a source of web consistency for some, APOD is still here. As during each of the 20 years of selecting…
A Colorful Lunar Corona
What are those colorful rings around the Moon? A corona. Rings like this will sometimes appear when the Moon is seen through thin clouds. The effect is created by the quantum…
M101: The Pinwheel Galaxy
Why do many galaxies appear as spirals ? A striking example is M101 , shown above , whose relatively close distance of about 27 million light years allows it to be studied in some…
1000 Sols
Shortly before Mars' June 2015 conjunction, the Curiosity Rover celebrated 1000 sols on the red planet . After its August 5, 2012 landing, Curiosity's 1000th sol or martian day on…
The Medusa Nebula
Braided, serpentine filaments of glowing gas suggest this nebula's popular name, The Medusa Nebula. Also known as Abell 21, this Medusa is an old planetary nebula some 1,500…
The Light, the Dark, and the Dusty
This colorful skyscape spans about three full moons (1.5 degrees) across nebula rich starfields along the plane of our Milky Way Galaxy in the royal northern constellation Cepheus…
Fly Over Dwarf Planet Ceres
What would it look like to fly over dwarf planet Ceres? Animators from the German Aerospace Center recently took actual images and height data from NASA's robotic Dawn mission --…
Galaxy NGC 7714 After Collision
Is this galaxy jumping through a giant ring of stars? Probably not. Although the precise dynamics behind the featured image is yet unclear, what is clear is that the pictured…
The Milky Way over the Temple of Poseidon
What's that glowing in the distance? Although it may look like a lighthouse , the rays of light near the horizon actually emanate from the Temple of Poseidon at Cape Sounion ,…
NGC 3132: The Eight Burst Nebula
It's the dim star, not the bright one, near the center of NGC 3132 that created this odd but beautiful planetary nebula . Nicknamed the Eight-Burst Nebula and the Southern Ring…
Into the Void
Fifty years ago , on June 3, 1965, Edward White stepped out of the orbiting Gemini 4 spacecraft to become the first US astronaut to walk in space . White is captured in this photo…
Green Flash at Moonrise
Follow a sunset on a clear day against a distant horizon and you might glimpse a green flash just as the Sun disappears, the sunlight briefly refracted over a long sight-line…
NGC 2419: Intergalactic Wanderer
Three objects stand out in this thoughtful telescopic image , a view toward the mostly stealthy constellation Lynx . The two brightest (the spiky ones) are nearby stars. The third…
Flyby Image of Saturn's Sponge Moon Hyperion
Why does this moon look like a sponge? To better investigate, NASA and ESA sent the Saturn-orbiting robotic spacecraft Cassini zooming past Saturn 's moon Hyperion , once again,…
Polaris and Comet Lovejoy
One of these two bright sky objects is moving. On the right is the famous star Polaris. Although only the 45th brightest star in the sky, Polaris is famous for appearing…
Pulsating Aurora over Iceland
Why do some auroras pulsate? No one is sure. Although this unusual behavior has been known for a long time, the cause remains an active topic of research. Featured here is a…
Supernova 1994D and the Unexpected Universe
Long ago, far away, a star exploded. Supernova 1994D , visible as the bright spot on the lower left, occurred in the outskirts of disk galaxy NGC 4526 . Supernova 1994D was not of…
Messier Craters in Stereo
Many bright nebulae and star clusters in planet Earth's sky are associated with the name of astronomer Charles Messier , from his famous 18th century catalog. His name is also…
Saturn at Opposition
Telescopic observers on Earth have been treated to spectacular views of Saturn lately as the ringed planet reached its 2015 opposition on May 23 at 0200 UT. Of course opposition…
Nearby Spiral Galaxy NGC 4945
Large spiral galaxy NGC 4945 is seen edge-on near the center of this cosmic galaxy portrait . In fact, NGC 4945 is almost the size of our own Milky Way Galaxy . Its own dusty…
Approaching Pluto
Here comes Pluto. NASA's robotic New Horizons spacecraft is now beyond the orbit of Neptune and closing fast on the Solar System's most famous unexplored world. The featured time…
Starburst Galaxy M94
What could cause the center of M94 to be so bright? Spiral galaxy M94 has a ring of newly formed stars surrounding its nucleus, giving it not only an unusual appearance but also a…
The Galaxy Tree
First came the trees. In the town of Salamanca , Spain , the photographer noticed how distinctive a grove of oak trees looked after being pruned . Next came the galaxy. The…
Viewing discoveries from 17 June 2015 through 25 May 2015.