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.
Video of a Green Flash
Many think it is just a myth. Others think it is true but its cause isn't known. Adventurers pride themselves on having seen it. It's a green flash from the Sun. The truth is the…
All of These Space Images are Fake Except One
Why would you want to fake a universe? For one reason -- to better understand our real universe . Many astronomical project s seeking to learn properties of our universe now start…
A Filament Leaps from the Sun
Why, sometimes, does part of the Sun's atmosphere leap into space? The reason lies in changing magnetic fields that thread through the Sun's surface. Regions of strong surface…
The Cat's Eye Nebula in Optical and X-ray
To some it looks like a cat's eye. To others, perhaps like a giant cosmic conch shell. It is actually one of brightest and most highly detailed planetary nebula known, composed of…
The Galaxy Between Two Friends
On an August night two friends enjoyed this view after a day's hike on the Plateau d'Emparis in the French Alps. At 2400 meters altitude the sky was clear. Light from a setting…
The Dark Seahorse in Cepheus
Light-years across, this suggestive shape known as the Seahorse Nebula appears in silhouette against a rich, luminous background of stars. Seen toward the royal northern…
NGC 147 and NGC 185
Dwarf galaxies NGC 147 (left) and NGC 185 stand side by side in this sharp telescopic portrait. The two are not-often-imaged satellites of M31, the great spiral Andromeda Galaxy ,…
The Horsehead and Flame Nebulas
The Horsehead Nebula is one of the most famous nebulae on the sky. It is visible as the dark indentation to the orange emission nebula at the far right of the featured picture .…
SN Requiem: A Supernova Seen Three Times So Far
We've seen this same supernova three times -- when will we see it a fourth? When a distant star explodes in a supernova , we're lucky if we see it even once. In the case of AT…
A Waterfall and the Milky Way
The dream was to capture both the waterfall and the Milky Way together. Difficulties included finding a good camera location, artificially illuminating the waterfall and the…
Dark Matter in a Simulated Universe
Is our universe haunted? It might look that way on this dark matter map. The gravity of unseen dark matter is the leading explanation for why galaxies rotate so fast , why…
A Rorschach Aurora
If you see this as a monster's face, don't panic. It's only pareidolia , often experienced as the tendency to see faces in patterns of light and shadow. In fact, the startling…
Haunting the Cepheus Flare
Spooky shapes seem to haunt this dusty expanse, drifting through the night in the royal constellation Cepheus . Of course, the shapes are cosmic dust clouds visible in dimly…
Mirach's Ghost
As far as ghosts go , Mirach's Ghost isn't really that scary . Mirach's Ghost is just a faint, fuzzy galaxy, well known to astronomers, that happens to be seen nearly along the…
NGC 6995: The Bat Nebula
Do you see the bat? It haunts this cosmic close-up of the eastern Veil Nebula . The Veil Nebula itself is a large supernova remnant, the expanding debris cloud from the death…
Jupiter Rotates
Observe the graceful twirl of our Solar System's largest planet. Many interesting features of Jupiter's enigmatic atmosphere, including dark belts and light zones, can be followed…
Road to the Galactic Center
Does the road to our galaxy's center go through Monument Valley ? It doesn't have to, but if your road does -- take a picture. In this case, the road is US Route 163 and iconic…
Halloween and the Ghost Head Nebula
Halloween's origin is ancient and astronomical. Since the fifth century BC, Halloween has been celebrated as a cross-quarter day , a day halfway between an equinox (equal day /…
3D Bennu
Put on your red/blue glasses and float next to asteroid 101955 Bennu . Shaped like a spinning toy top with boulders littering its rough surface, the tiny Solar System world is…
A Comet and a Crab
This pretty field of view spans over 2 degrees or 4 full moons on the sky, filled with stars toward the constellation Taurus, the Bull. Above and right of center in the frame you…
SH2-308: The Dolphin-head Nebula
Blown by fast winds from a hot, massive star, this cosmic bubble is huge. Cataloged as Sharpless 2-308 it lies some 5,000 light-years away toward the constellation of the Big Dog…
Lucy Launches to Eight Asteroids
Why would this mission go out as far as Jupiter -- but then not visit Jupiter? Lucy's plan is to follow different leads about the origin of our Solar System than can be found at…
Palomar 6: Globular Star Cluster
Where did this big ball of stars come from? Palomar 6 is one of about 200 globular cluster s of stars that survive in our Milky Way Galaxy . These spherical star-balls are older…
Earthshine Moon over Sicily
Why can we see the entire face of this Moon? When the Moon is in a crescent phase, only part of it appears directly illuminated by the Sun . The answer is earthshine , also known…
Viewing discoveries from 10 November 2021 through 18 October 2021.