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.
Another Comet LINEAR Breaks Up
Last year, a different comet LINEAR (C/1999 S4) broke up. This year, a comet first imaged by the Lincoln Near Asteroid Research (LINEAR) telescope in New Mexico on 2001 January 3,…
Sagittarius Star Cloud
Stars come in all different colors. The color of a star indicates its surface temperature , an important property used to assign each star a spectral type . Most stars in the…
Damage to Apollo 13
In April of 1970 , after an oxygen tank exploded and crippled their service module, the Apollo 13 astronauts were forced to abandon plans to make the third human lunar landing .…
HD 82943: Planet Swallower
Stars like HD 82943 are main sequence G dwarf stars with temperatures and compositions similar to the Sun . Also like the Sun, HD 82943 is known to have at least two giant planets…
Solar Neutrino Astronomy
Neutrinos are subatomic particles generated by the nuclear reactions which power stars like our Sun . Flying outward from the Sun's core, they easily pass through the Sun (and…
The Center of the Circinus Galaxy in X-Rays
Are black holes the cause of X-rays that pour out from the center of the Circinus galaxy ? A new high-resolution image from the orbiting Chandra X-ray Observatory has resolved the…
A Radar Image of Venus
The largest radio telescopes in the world are working together to create a new map of the surface of Venus. The surface of Venus is unusually hidden by a thick atmosphere of…
A Cerro Tololo Sky
High atop a Chilean mountain lies one of the premier observatories of the southern sky: Cerro Tololo . Pictured above is one of the premier telescopes of the Cerro Tololo…
Crater Copernicus
One of the more prominent craters on the Moon is named Copernicus . Copernicus is a large young crater visible with binoculars slightly northwest of the center of the Moon's…
Shuttle Moon
As a gorgeous full Moon rose above the eastern horizon on February 7, the Space Shuttle Atlantis streaked skyward towards an orbital rendezvous with the International Space…
X-Ray Rainbows
A drop of water or prism of glass can spread out visible sunlight into a rainbow of colors . In order of increasing energy, the well known spectrum of colors in a rainbow runs…
Spirals On Edge
Spiral galaxies viewed face-on display a grand design , with graceful spiral arms traced by bright star clusters and glowing stellar nurseries. When seen edge-on, their appearance…
Space Station Shows Off New Robot Arm
The International Space Station (ISS) continues to grow. Last month, the crew of the Space Shuttle Endeavor delivered new Logistics Modules and installed the new Canadarm2 on the…
GRO J1655-40: Evidence for a Spinning Black Hole
In the center of a swirling whirlpool of hot gas is likely a beast that has never been seen directly: a black hole . Studies of the bright light emitted by the swirling gas…
One Hundred-Kilometer Terrain on Venus
Even the hot and cracked surface of Venus has rolling hills. Although never actually photographed from up-close, images of the Venusian surface like that shown above have been…
The Pleiades Star Cluster
It is the most famous star cluster on the sky. The Pleiades can be seen without binoculars from even the depths of a light-polluted city . Also known as the Seven Sisters and M45…
Shepard Flies Freedom 7
Forty years ago today ( May 5, 1961 ), at the dawn of the space age , NASA controllers “lit the candle” and sent Alan Shepard arcing into space atop a Redstone rocket . The…
Protoplanetary Survivors in Orion
The Orion Nebula is a nuturing stellar nursery filled with hot young stars and their natal clouds of gas and dust. But for planetary systems , the active star-forming region can…
Far Side of the Sun
You may think it's impossible to see through the Sun , but maps of the Sun's far side are now made routinely by instruments on board the sun-staring SOHO spacecraft. This is one…
Planet Building in HD 100546
More than 100 billion boulders may be swarming in the disk around nearby star HD 100546 . In a scene thought similar to the early years of our own Solar System , ever larger rocks…
Antarctica Hears Little Normal Matter in the Big Bang
On the frozen ice near the bottom of our world, increasingly sophisticated instruments listen for a more precise echo of how our universe started. Sunday, independent…
Approaching the International Space Station
Earlier this month the crew of the US Space Shuttle Endeavor took in this view as they approached the developing International Space Station (ISS). The Endeavor and ISS crew…
Ice Fishing for Cosmic Neutrinos
Scientists are melting holes in the bottom of the world. In fact, several holes have been melted near the South Pole , and they are now being used as astronomical observatories.…
The Moon and All the Crashes
A clear blue summer sky finally grows dark and the new telescope, hastily set up in the backyard, generates excitment and anticipation. “I bought it for the kids.”, Dad assures…
Viewing discoveries from 21 May 2001 through 28 April 2001.