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.
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…
Universe Age from Microwave Background
The above sky map tells us the universe is 13.7 billion years old -- but how? At first look, one only sees the microwave glow of gas from our Milky Way Galaxy , coded red, and a…
Southwest Mercury
The planet Mercury resembles a moon. Mercury 's old surface is heavily cratered like many moons. Mercury is larger than most moons but smaller than Jupiter 's moon Ganymede and…
Happy Birthday Jules Verne
One hundred seventy-five years ago (on February 8th), Jules Verne was born in Nantes, France. Inspired by a lifelong fascination with machines, Verne wrote visionary works about…
The Heart in NGC 346
Yes, it's Valentine's Day (!) and looking toward star cluster NGC 346 in our neighboring galaxy the Small Magellanic Cloud , astronomers have noted this heart-shaped cloud of hot,…
The Eagle Nebula from CFHT
Bright blue stars are still forming in the dark pillar s of the Eagle Nebula . Made famous by a picture from the Hubble Space Telescope in 1995, the Eagle Nebula shows the…
WMAP Resolves the Universe
Analyses of a new high-resolution map of microwave light emitted only 380,000 years after the Big Bang appear to define our universe more precisely than ever before. The eagerly…
Dumbbell Nebula Close-Up from Hubble
What causes unusual knots of gas and dust in planetary nebulas ? Seen previously in the Ring Nebula , the Helix Nebula , and NGC 2392 , the knots' existence was not predicted…
Comet NEAT Approaches the Sun
A comet may likely become visible to the unaided eye over the next few days above the horizon where the Sun has just set. Comet NEAT (C/ 2002 V1) , discovered last November, has…
COBE Dipole: Speeding Through the Universe
Our Earth is not at rest. The Earth moves around the Sun . The Sun orbits the center of the Milky Way Galaxy . The Milky Way Galaxy orbits in the Local Group of Galaxies . The…
AB Aurigae: How To Make Planets
This enhanced Hubble Space Telescope image shows in remarkable detail the inner portion of the disk of dust and gas surrounding the star AB Aurigae. Knots of material, visible…
Orion on Film
Orion , the Hunter, is one of the most easily recognizable constellations in planet Earth's night sky . But Orion's stars and nebulae don't look quite as colorful to the eye as…
X-Rays from M83
Bright and beautiful spiral galaxy M83 lies a mere twelve million light-years from Earth, toward the headstrong constellation Hydra . Sweeping spiral arms, prominent in visible…
Unusual Gullies and Channels on Mars
What could have formed these unusual channels? Inside Newton Basin on Mars , numerous narrow channels run from the top down to the floor. The above picture covers a region…
Viewing discoveries from 28 February 2003 through 5 February 2003.