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.

Venus' Once Molten Surface
If you could look at Venus with radar eyes - this is what you might see. This computer reconstruction of the surface of Venus was created from data from the Magellan spacecraft.…

Inside the Elephant's Trunk
In December of 2003, the world saw spectacular first images from the Spitzer Space Telescope , including this penetrating interior view of an otherwise opaque dark globule known…

Sideways Galaxy NGC 3628
Dark dust lanes cutting across the middle of this gorgeous island universe strongly hint that NGC 3628 is a spiral galaxy seen sideways . About 35 million light-years away in the…

Solar Eclipse in View
Friday's solar eclipse will be a rare hybrid - briefly appearing as either an annular eclipse or a total eclipse when viewed from along the narrow track of the Moon's shadow .…

The M7 Open Star Cluster in Scorpius
M7 is one of the most prominent open clusters of stars on the sky. The cluster, dominated by bright blue stars , can be seen with the naked eye in a dark sky in the tail of the…

Light From A Distant Planet
Light emitted by a planet far beyond our Solar System has been identified for the first time. The planet, illustrated in the above drawing , had its light detected by comparing…

NGC 1316: After Galaxies Collide
How did this strange-looking galaxy form? Astronomers turn detectives when trying to figure out the cause of unusual jumbles of stars, gas, and dust like NGC 1316 . A preliminary…

The Galactic Center Radio Arc
What causes this unusual structure near the center of our Galaxy? The long parallel rays slanting across the top of the above radio image are known collectively as the Galactic…

Cyg X-1: Can Black Holes Form in the Dark?
The formation of a black hole from the collapsing core of a massive star is thought to be heralded by a spectacular supernova explosion. Such an extremely energetic collapse is…

Water On Mars
Can you help discover water on Mars? Finding water on different regions on Mars has implications for understanding its complex geologic history , the possible existence of past…

Gamma-Ray Earth
The pixelated planet above is actually our own planet Earth seen in gamma rays - the most energetic form of light. In fact, the gamma rays used to construct this view pack over 35…

ULXs in M74
In visual appearance, M74 is a nearly perfect face-on spiral galaxy, about 30 million light-years away toward the constellation Pisces. The red blotches seen in this composite…

Crescents of Titan and Dione
What would it be like to see a sky with many moons? Such is the sky above Saturn . When appearing close to each other, moons will show a similar phase . A view with two of the…

A Tether in Space
One of the greatest unrequited legends of outer space is the tether. Tethers , long strands of material, hold the promise of stabilizing satellites , generating electricity , and…

The Einstein Cross Gravitational Lens
Most galaxies have a single nucleus -- does this galaxy have four? The strange answer leads astronomers to conclude that the nucleus of the surrounding galaxy is not even visible…

Composite Crab
The Crab Pulsar, a city-sized, magnetized neutron star spinning 30 times a second, lies at the center of this composite image of the inner region of the well-known Crab Nebula .…

Huygens Discovers Luna Saturni
In 1655, three hundred fifty years ago on this date, Dutch astronomer Christiaan Huygens discovered Luna Saturni - now known as Saturn's moon Titan. To celebrate, consider this…

Simeis 147: Supernova Remnant
It's easy to get lost following the intricate filaments in this detailed image of faint supernova remnant Simeis 147. Seen towards the constellation Taurus it covers nearly 3…

A Dust Devil Swirling on Mars
What is that wisp on the horizon? Scientists think that the slight white apparition is actually a Martian dust devil that was caught swirling across Mars . The above image was…

To Fly Free in Space
At about 100 meters from the cargo bay of the space shuttle Challenger, Bruce McCandless II was further out than anyone had ever been before. Guided by a Manned Maneuvering Unit…

Orion's Horsehead Nebula
The Horsehead Nebula is one of the most famous nebulae on the sky. It is visible as the dark indentation to the red emission nebula seen above and to the right of center in the…

The Equal Night
Today, the Sun crosses the celestial equator heading north, marking the Vernal Equinox -- the first day of spring in the Northern Hemisphere and autumn in the south . Equinox…

NGC 2266: Old Cluster in the New General Catalog
The New General Catalog of star clusters and nebulae really isn't so new. In fact, it was published in 1888 - an attempt by J. L. E. Dreyer to consolidate the work of astronomers…

Moon, Mercury, Monaco
Low on the western horizon after sunset, a slender crescent Moon and wandering planet Mercury join the lights of Menton and Monaco along the French Riviera. Astronomer Vincent…
Viewing discoveries from 10 April 2005 through 18 March 2005.