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 Galactic Center Across the Infrared
The center of our Galaxy is obscured in visible light by dark dust that rotates with the stars in the Galactic Plane . In this century, however, sensors have been developed that…
Io: Moon Over Jupiter
How big is the Jovian moon Io ? The most volcanic body in the Solar System, Io (usually pronounced “EYE-oh”) is 3,600 kilometers in diameter, about the size of planet Earth's…
Many Moons
Whimsical and creative, this multiple exposure suggests that planet Earth's sky could be very dramatic indeed if it were graced by many moons . And in James Thurber's well-known…
Young Star Clusters in an Old Galaxy
Elliptical galaxy NGC 4365 is old, probably about 12 billion years old. Like most elliptical galaxies , this galaxy was thought to be full of old stars too, its burst of star…
Interstellar Dust Bunnies of NGC 891
What is going on in NGC 891 ? This galaxy appeared previously to be very similar to our own Milky Way Galaxy : a spiral galaxy seen nearly edge-on. However, recent high-resolution…
The Average Color of the Universe
What color is the universe? More precisely, if the entire sky was smeared out, what color would the final mix be? This whimsical question came up when trying to determine what…
The Fox Fur Nebula
The nebula surrounding bright star S Mon is filled with dark dust and glowing gas. The strange shapes originate from fine interstellar dust reacting in complex ways with the…
Ida and Dactyl: Asteroid and Moon
This asteroid has a moon ! The robot spacecraft Galileo currently exploring the Jovian system , encountered and photographed two asteroids during its long journey to Jupiter . The…
A Deep Field In The Southern Sky
This deep view of the cosmos is the sequel to the 1995 hit Hubble Space Telescope Deep Field . Billed as the Hubble Deep Field South , it was produced by pointing the space…
Lunar Module at Taurus-Littrow
Can the Hubble Space Telescope take a picture that shows the Apollo lunar modules on the Moon? With its 2.4 meter diameter mirror , the smallest object that the Hubble can resolve…
Carving Ma'adim Vallis
Just as erosion from the Colorado River carved the Grand Canyon on Earth, a river of flood water may have carved Ma'adim Vallis, one of the largest canyons on Mars . Researchers…
In the Center of the Trifid Nebula
Clouds of glowing gas mingle with lanes of dark dust in the Trifid Nebula , a star forming region toward the constellation of Sagittarius . In the center, the three huge dark dust…
Venus and Jupiter Over Belfast
Venus and Jupiter appeared to glide right past each other earlier this month. In a slow day-by-day march, Jupiter sank into the sunset horizon while Venus remained high and…
The Sun's Heliosphere & Heliopause
Where does the Sun's influence end? Nobody is sure. Out past the orbits of Neptune and Pluto extends a region named the heliosphere where the Sun's magnetic field and particles…
Asteroids in the Distance
Rocks from space hit Earth every day. The larger the rock, though, the less often Earth is struck. Many kilograms of space dust pitter to Earth daily. Larger bits appear initially…
Io: The Prometheus Plume
Two sulfurous eruptions are visible on Jupiter's volcanic moon Io in this color composite Galileo image . On the left, over Io's limb, a new bluish plume rises about 86 miles…
Zimbabwe Sunset
Today's scheduled geocentric astronomical event is the Solstice , with the Sun reaching its northernmost declination at 13 hours 24 minutes Universal Time . For denizens of planet…
Bright Galaxy M81
Big and beautiful spiral galaxy M81 , in the northern constellation Ursa Major , is one of the brightest galaxies visible in the skies of planet Earth. This superbly detailed view…
The Moon & Venus Over Geneva
The Moon, fresh from a biting encounter with the Sun last week , appeared next to threaten Venus. The waxing Moon appeared to glide right past, however, just a few degrees away .…
IC 4406: A Seemingly Square Nebula
How can a round star make a square nebula? This conundrum comes to light when studying planetary nebulae like IC 4406. Evidence indicates that IC 4406 is likely a hollow cylinder,…
NGC 4697: X-Rays from an Elliptical Galaxy
The many bright, point-like sources in this Chandra Observatory x-ray image lie within NGC 4697, an elliptical galaxy some 40 million light-years away towards Virgo . Like other…
Jupiter's Rings Revealed
Why does Jupiter have rings? Jupiter's rings were discovered in 1979 by the passing Voyager 1 spacecraft , but their origin was a mystery. Data from the Galileo spacecraft…
MyCn18: An Hourglass Nebula
The sands of time are running out for the central star of this hourglass-shaped planetary nebula . With its nuclear fuel exhausted, this brief, spectacular, closing phase of a…
55 Cancri: Familiar Planet Discovered
Is our Solar System unique? The discovery of a Jupiter -like planet in a Jupiter-like orbit around nearby Sun -like star 55 Cancri , announced yesterday, gives a new indication…
Viewing discoveries from 7 July 2002 through 14 June 2002.