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.
Aerogel For STARDUST
On February 7th, this honey comb of aluminum cells filled with aerogel was launched on the STARDUST mission to interplanetary space. STARDUST's goal is to capture dust from a…
Hickson Compact Group 40
Galaxies , like stars, frequently form groups. A group of galaxies is a system containing more than two galaxies but less than the tens or hundreds typically found in a cluster of…
The Large and Small of M87
The small core of elliptical galaxy M87 appears to be energizing its whole galactic neighborhood. Recent images from the Very Large Array (VLA) of radio telescopes indicate that…
La Niña Earth
La Niña is a temporary climate change caused by unusually cold water in the central Pacific Ocean . Cold water topping an unusually low sea level is shown as purple in the above…
Dark Sky, Bright Sun
In low Earth orbit there is not enough atmosphere to diffuse and scatter sunlight, so shadows are black and the sky is dark - even when the Sun shines. The harsh lighting produced…
Pluto: The Frozen Planet
This portrait of Pluto and its companion Charon was taken by the Hubble Space Telescope in 1994. Pluto is usually the most distant planet from the Sun but because of its eccentric…
Lunar Close-Up
Late last month, NASA's Lunar Prospector spacecraft moved in for a closer look at the Moon . Now entering an extended mission phase, controllers have reduced the altitude of this…
A Disk and Jet in Haro 6-5B
Planets condense from disks. Several new Hubble Space Telescope pictures of stars surrounded by disks were released earlier this week. Since the glare of the central star usually…
GRB 990123 Host Galaxy Imaged
Do the powerful explosions known as gamma-ray bursts (GRBs) originate in galaxies? This subject took on new light yesterday with the release of a Hubble Space Telescope image of…
A Supernova Star-Field
Bright stars don't last forever. A bright star similar to others in this field exploded in a spectacular supernova that was witnessed on Earth in 1987 . The result is visible even…
The Solar Wind Emerges
Winds of fast particles blow out from the Sun , but why ? Astronomers came a step closer to answering this question recently by making detailed observations of the high-speed wind…
Titan: Saturn's Smog Moon
The largest moon of Saturn is a rare wonder. Titan is the only one of Saturn's moons with an atmosphere, and one of only two moons in the Solar System with this distinction…
The First Explorer
The first US spacecraft was Explorer 1 . The cylindrical 30 pound satellite was launched (above) as the fourth stage of a Jupiter-C rocket (a modified US Army Redstone ballistic…
HR 4796A: Not Saturn
These are not false-color renderings of the latest observations of Saturn's magnificent rings . Instead, the panels show a strikingly similar system on a much larger scale - a…
Spiral Sunspot
Spiral galaxies abound in the universe, but spiral sunspots are definitely an unusual twist. This distinctive spiral-shaped sunspot caught the attention of National Solar…
A Galactic Mushroom Cloud
Part of our Galaxy is exploding. Recent radio observations show new details of hot gas expanding rapidly from an energetic star-forming region in our Galactic disk out into our…
The Orion Nebula from Subaru
The Orion Nebula (M42) shows a host of treasures when viewed in infrared light. Some stars in the Trapezium , an open cluster of stars at the center, are only visible in infrared…
The Subaru Telescope
Last week, Japan's new Subaru Telescope made its first observations of the sky. The gray building housing Subaru is visible just left of the white Keck domes near the photo's…
Welcome to the Planet Earth
Welcome to Planet Earth , the third planet from a star named the Sun . The Earth is shaped like a sphere and composed mostly of rock . Over 70 percent of the Earth's surface is…
Stereo Saturn
Get out your red/blue glasses and launch yourself into this stereo picture of Saturn! The picture is actually composed from two images recorded weeks apart by the Voyager 2…
The Moon In January
Reckoning dates by Universal Time, the next full moon will be on Sunday, January 31. Since the last was on January 2nd, Sunday's full moon will be the second this month. Perhaps…
The Galactic Center - A Radio Mystery
Tuning in to the center of our Milky Way galaxy, radio astronomers explore a complex, mysterious place. A premier high resolution view, this startlingly beautiful picture covers a…
Hypatia of Alexandria
Sixteen hundred years ago, Hypatia became one of the world's leading scholars in mathematics and astronomy. Hypatia 's legendary knowledge, modesty, and public speaking ability…
M17: The Omega Nebula
The Omega Nebula contains glowing gas , dark dust , and some unusually massive stars . Also known as the M17 and the Swan Nebula , the Omega Nebula is about 5000 light-years away,…
Viewing discoveries from 18 February 1999 through 26 January 1999.