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.
WIRO at Jupiter
Gazing out over the mountaintops from the Wyoming InfraRed Observatory (WIRO), astronomers recently recorded this bizarre looking image of the solar system's ruling planet, gas…
Lunar Farside from Apollo 11
The far side of the Moon is rough and filled with craters . By comparison, the near side of the Moon , the side we always see, is relatively smooth. Since the Moon is rotation…
Iridescent Clouds
Why would clouds appear to be different colors? A relatively rare phenomenon known as iridescent clouds can show unusual colors vividly or a whole spectrum of colors…
M101: The Pinwheel Galaxy
Why do many galaxies appear as spirals ? A striking example is M101, shown above , whose relatively close distance of about 22 million light years allow it to be studied in some…
Farewell Jupiter
Next stop: Saturn. The Cassini spacecraft , launched from Earth in 1997, has now swung past Jupiter and should arrive at Saturn in the year 2004. Pictured to the left is a parting…
Solar Sail
Nearly 400 years ago astronomer Johannes Kepler observed comet tails blown by a solar breeze and suggested that vessels might likewise navigate through space using appropriately…
The Star Trails of Kilimanjaro
The night had no moon, but the stars were out. And camped at 16,000 feet on Mt. Kilimanjaro , photographer Dan Heller recorded this marvelous 3 1/2 hour long exposure. Here the…
Comet NEAT in Southern Skies
After last month's dramatic swoop past the Sun, Comet NEAT (C/2002 V1) appeared as a naked-eye comet , emerging from the evening twilight in planet Earth's southern skies. On…
Where People Live on Planet Earth
Where do people live on Planet Earth ? Although people inhabit every continent , the highest population densities occur in Asia . Sparsely inhabited regions occur on virtually…
In the Center of the Lagoon Nebula
The center of the Lagoon Nebula is busy with the awesome spectacle of star formation . Visible in the lower left, at least two long funnel-shaped clouds, each roughly half a…
Will the Universe End in a Big Rip?
How will our universe end? Recent speculation now includes a pervasive growing field of mysterious repulsive energy that rips virtually everything apart. Although the universe…
In the Center of the Trapezium
Start with the constellation of Orion . Near Orion's belt is a fuzzy area known as the Great Nebula of Orion or M42 . In this nebula is a bright star cluster known as the…
Stereo Eros
Get out your red/blue glasses and float next to asteroid 433 Eros , 170 million kilometers away! Orbiting the Sun once every 1.8 earth-years, asteroid Eros is a diminutive 40 x 14…
Fox Fur, the Unicorn, and a Christmas Tree
Glowing hydrogen gas fills this gorgeously detailed sky view centered on the variable star S Mon in the faint but fanciful constellation Monoceros , the Unicorn. A star forming…
When Moons and Shadows Dance
It's no wonder Jupiter is a favorite target for even modest earthbound telescopes. The most massive planet in the solar system with four of the largest moons also boasts the…
Anticrepuscular Rays Over Horseshoe Canyon
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…
M42: Wisps of the Orion Nebula
The Great Nebula in Orion , an immense, nearby starbirth region , is probably the most famous of all astronomical nebulas . Here, glowing gas surrounds hot young stars at the edge…
Comet Neat Passes an Erupting Sun
As Comet NEAT flared last week, the Sun roared . Just as the comet swooped inside the orbit of Mercury and developed a long and flowing tail of gas and dust , the Sun emitted a…
A Twisted Solar Eruptive Prominence
A huge eruptive prominence is seen moving out from our Sun in this condensed half-hour time-lapse sequence. Ten Earth s could easily fit in the “claw” of this seemingly solar…
Infrared Saturn
This delightfully detailed false-color image of Saturn was taken in January 1998 by the orbiting Hubble Space Telescope. The picture is a combination of three images from Hubble's…
Melting Snow and the Gullies of Mars
Tantalizing images of gullies on Mars have offered striking evidence for recent flows of liquid water. But Mars is too cold and its atmosphere too thin for liquid water to exist…
Cold Wind from the Boomerang Nebula
A cold wind blows from the central star of the Boomerang Nebula. Seen here in a detailed false-color image recorded in 1998 by the Hubble Space Telescope , the nebula lies about…
Pauli Exclusion Principle: Why You Don't Implode
Why doesn't matter just bunch up? The same principle that keeps neutron stars and white dwarf stars from imploding also keeps people from imploding and makes normal matter mostly…
Candor and Ophir Chasmata
First imaged by the Mariner 9 spacecraft, Valles Marineris , the grand canyon of Mars, is a system of enormous depressions called chasmata that stretch some 4,000 kilometers along…
Viewing discoveries from 13 March 2003 through 18 February 2003.