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.
Above Earth, Fixing Hubble
What is that astronaut doing? Fixing the Hubble Space Telescope . During the fourth servicing mission to upgrade and fix Hubble, astronaut Michael Good can be seen attached to the…
Sagittarius and the Central Milky Way
What does the center of our Milky Way Galaxy look like? In visible light, no one knows! It is not possible to see the Galactic center in light our eyes are sensitive to because…
Moon Rays Over Thurso Castle
What's happening over that castle? While waiting for the Moon to rise last month in Thurso , Scotland , amateur astrophotographer Stewart Watt took a three minute exposure of the…
Mimas: Small Moon with a Big Crater
Whatever hit Mimas nearly destroyed it. What remains is one of the largest impact craters on one of Saturn 's smallest moons. The crater, named Herschel after the 1789 discoverer…
Atlantis and Hubble Side by Side
On Wednesday, May 13, two, tiny, fast moving spots crossed an otherwise featureless solar disk. Not sunspots though, the dark blemishes were silhouettes of the shuttle orbiter…
M97: The Owl Nebula
The Owl Nebula is perched in the sky about 2,600 light-years away toward the bottom of the Big Dipper's bowl. Also cataloged as M97 , the 97th object in Messier's well-known list,…
Elusive Jellyfish Nebula
Normally faint and elusive, the Jellyfish Nebula is caught in this alluring wide-field telescopic view. Flanked by two yellow-tinted stars, Mu and Eta Geminorum, at the foot of a…
A Space Shuttle Before Dawn
This shuttle has launched to space. Pictured above, the Space Shuttle Atlantis sat on Launch Pad 39A before dawn last month as it was prepared for the launch. The shuttle orbiter…
A Circumhorizontal Arc Over Ohio
Why would clouds appear to be different colors? The reason here is that ice crystals in distant cirrus clouds are acting like little floating prisms . Sometimes known as a fire…
Forty Thousand Meteor Origins Across the Sky
Where do meteors come from? Visible meteors are typically sand-sized grain s of ice and rock that once fragmented from comets. Many a meteor shower has been associated with a…
M31: The Andromeda Galaxy
Andromeda is the nearest major galaxy to our own Milky Way Galaxy . Our Galaxy is thought to look much like Andromeda . Together these two galaxies dominate the Local Group of…
A Starry Night in Brazil
This panoramic image tracing constellations in the southern sky shows off a beautiful vista toward the center of our Milky Way Galaxy. It was recorded just last month near the…
Galaxies of the Perseus Cluster
This colorful telescopic skyscape is filled with galaxies that lie nearly 250 million light-years away, the galaxies of the Perseus cluster. Their extended and sometimes…
A Halo for NGC 6164
Beautiful emission nebula NGC 6164 was created by a rare, hot, luminous O-type star, some 40 times as massive as the Sun. Seen at the center of the cosmic cloud, the star is a…
A Spring Sky Over Hirsau Abbey
What's in the sky tonight? When strolling outside just after sunset, even if just going out to your car, a casual glance upwards can reveal a beautiful night sky also seen by many…
Titan Beyond the Rings
When orbiting Saturn, be sure to watch for breathtaking superpositions of moons and rings. One such picturesque vista was visible recently to the robot Cassini spacecraft now…
Rembrandt Impact Basin on Mercury
Why do portions of this huge crater on Mercury have so much iron? The unusual Rembrandt impact basin was discovered recently in images taken during the robotic MESSENGER…
NGC 2392 Nebula from Hubble
In 1787, astronomer William Herschel discovered NGC 2392 . From the ground, NGC 2392 resembles a person's head surrounded by a parka hood. In 2000, the Hubble Space Telescope…
The Whale Galaxy
NGC 4631 is a big beautiful spiral galaxy. Seen edge-on , it lies only 25 million light-years away in the well-trained northern constellation Canes Venatici . The galaxy's…
Lyrid Meteor and Milky Way
On April 22nd, the Lyrid Meteor Shower visited planet Earth's sky, an annual shower produced as the Earth plows through dust from the tail of comet Thatcher . Usually Lyrid meteor…
Framed by Clouds
Last Sunday's fading evening twilight featured a young crescent Moon along the western horizon. The young Moon also shared the sky with the lovely Pleiades star cluster and…
GRB 090423: The Farthest Explosion Yet Measured
An explosion so powerful it was seen clear across the visible universe was recorded in gamma-radiation last week by NASA's orbiting Swift Observatory . Farther than any known…
NGC 4565: Galaxy on the Edge
Is our Galaxy this thin? We believe so. Magnificent spiral galaxy NGC 4565 is likely similar to our own spiral galaxy, but viewed edge-on from far away. Also known as the Needle…
Prometheus Creating Saturn Ring Streamers
What's causing those strange dark streaks in the rings of Saturn? Prometheus . Specifically, an orbital dance involving Saturn's moon Prometheus keeps creating unusual light and…
Viewing discoveries from 20 May 2009 through 27 April 2009.