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.
The Hydra Cluster of Galaxies
The Hydra Cluster of Galaxies contains well over 100 bright galaxies - but perhaps fewer galaxies than might be expected from its mass. Clusters of galaxies are the largest…
Diffraction Spikes: When Stars Look Like Crosses
Unusual appendages around bright stars are commonplace, but never seem to be mentioned. What are they? First, a telescope brings starlight falling over a large area to a small…
Man Enters Space
Forty years ago, on April 12, 1961, Soviet cosmonaut Yuri Alexseyevich Gagarin became the first human in space. His remotely controlled Vostok 1 spacecraft lofted him to an…
GRB010222: Gamma-Ray Burst, X-Ray Afterglow
A fading afterglow from one of the most powerful explosions in the universe is centered in this false color image from the spacebased Chandra X-ray Observatory . The cosmic…
STS-1: First Shuttle Launch
On April 12, 1981, twenty years ago today, the space shuttle orbiter Columbia became the first shuttle to orbit the Earth. In this gorgeous time exposure , flood lights play on…
Large Sunspot Group AR 9393
The largest sunspot group of the past ten years crossed the surface of the Sun late last month and early this month. The group was designated Active Region 9393 as it was the…
M51: The Whirlpool Galaxy in Dust and Stars
The Whirlpool Galaxy is a classic spiral galaxy. At only 30 million light years distant and fully 60 thousand light years across, M51 , also known as NGC 5194, is one of the…
Mars Odyssey Lifts Off for Mars
Next stop: Mars. On Saturday the 2001 Mars Odyssey spacecraft lifted off from Cape Canaveral , Florida on a path to enter orbit around Mars in late October. Pictured above , a…
The Big Corona
Most photographs don't adequately portray the magnificence of the Sun 's corona. Seeing the corona first-hand during a total solar eclipse is best. The human eye can adapt to see…
Stereo Sun
This week's stereo offering features the now famous Active Region 9393, the largest sunspot group in the last 10 years. Viewed with red/blue glasses , the stereo pair of images…
Aurora Over New Zealand
Last weekend skygazers at middle and high latitudes around the globe were treated to expansive auroral displays as a magnetic storm raged around planet Earth . The storm was…
On the Origin of Gold
Where did the gold in your jewelry originate? No one is completely sure . The relative average abundance in our Solar System appears higher than can be made in the early universe…
Distant Supernova, Dark Energy
A pinpoint of light from a star that exploded over 10 billion light-years away is centered in the panel at the lower right, a cosmic snapshot of the most distant supernova . The…
New Stars Destroying NGC 1748
NGC 1748 cannot contain all the new stars it has formed. The young stars, the most massive of which are bright blue , emit so much energy they are pushing out and dispersing the…
Aurora Over Clouds
Aurorae usually occur high above the clouds. The auroral glow is created when fast-moving particles ejected from the Sun impact air molecules high in the Earth's atmosphere . An…
Americans Defeat Russians in First Space Quidditch Match
A historic first Space Quidditch match came to a spectacular conclusion last night as astronaut Michael Lopez-Alegria caught the Golden Snitch to give the Americans a hard fought…
Barsoom
“Yes, I have been to Barsoom again ...” begins John Carter in Edgar Rice Burroughs' 1913 science fiction classic “The Gods of Mars” . In Burroughs' novels describing Carter's…
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…
Aurora Alaskan Style
Have you checked the space weather report lately? With a coronal mass ejection (CME) headed our way and an immense sunspot group tracking across the solar photosphere , skygazers…
Chandra Deep Field
Officially the Chandra Deep Field - South , this picture represents the deepest ever x-ray image of the Universe. One million seconds of accumulated exposure time with the…
Swiss Cheese-Like Landscape on Mars
Why do parts of the south pole of Mars look like swiss cheese ? This little-understood landscape features flat-topped mesas nearly 4 meters high and circular indentations over 100…
Comet Hale-Bopp in the Outer Solar System
Whatever became of Comet Hale-Bopp ? The brightest comet in recent years has continued into the outer Solar System and is now farther from the Sun than Saturn . To the surprise of…
The Crab Nebula from VLT
The Crab Nebula , filled with mysterious filaments, is the result of a star that was seen to explode in 1054 AD . This spectacular supernova explosion was recorded by Chinese and…
The UV SMC from UIT
Translated from the “acronese” the title reads - The U ltra V iolet S mall M agellanic C loud from the U ltraviolet I maging T elescope. FYI, the four ultraviolet images used in…
Viewing discoveries from 16 April 2001 through 24 March 2001.