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.
Arp 273: Battling Galaxies from Hubble
What's happening to these spiral galaxies? Although details remain uncertain , there sure seems to be a titanic battle going on. The upper galaxy is labelled UGC 1810 by itself,…
Milky Way over Uruguayan Lighthouse
Can a lighthouse illuminate a galaxy? No, but in the featured image, gaps in light emanating from the Jose Ignacio Lighthouse in Uruguay appear to match up nicely, although only…
Passing Asteroid Arrokoth
What would it look like to pass asteroid Arrokoth? The robotic New Horizons spacecraft zoomed past Arrokoth in January, 3.5 years after the spacecraft passed Pluto. If this…
Young Stars in the Rho Ophiuchi Cloud
How do stars form? To help find out, astronomers created this tantalizing false-color composition of dust clouds and embedded newborn stars in infrared wavelengths with WISE, the…
The Star Streams of NGC 5907
Grand tidal streams of stars seem to surround galaxy NGC 5907 . The arcing structures form tenuous loops extending more than 150,000 light-years from the narrow, edge-on spiral,…
M16 and the Eagle Nebula
A star cluster around 2 million years young surrounded by natal clouds of dust and glowing gas, M16 is also known as The Eagle Nebula. This beautifully detailed portrait of the…
Mercury and the Quiet Sun
On November 11, 2019 the Sun was mostly quiet, experiencing a minimum in its 11 year cycle of activity . In fact, the only spot visible was actually planet Mercury, making a…
Mercury in Silhouette
The small, dark, round spot in this solar close up is planet Mercury. In the high resolution telescopic image, a colorized stack of 61 sharp video frames, a turbulent array of…
NGC 3717: A Nearly Sideways Spiral Galaxy
Some spiral galaxies are seen nearly sideways. Most bright stars in spiral galaxies swirl around the center in a disk, and seen from the side, this disk can appear quite thin.…
Lunar Craters Langrenus and Petavius
The history of the Moon is partly written in its craters. Pictured here is a lunar panorama taken from Earth featuring the large craters Langrenus , toward the left, and Petavius…
A Mercury Transit Sequence
Tomorrow -- Monday -- Mercury will cross the face of the Sun , as seen from Earth. Called a transit , the last time this happened was in 2016 . Because the plane of Mercury's…
Saturn the Giant
On May 25, 1961 U.S. president John Kennedy announced the goal of landing astronauts on the Moon by the end of the decade. By November 9, 1967 this Saturn V rocket was ready for…
NGC 3572 and the Southern Tadpoles
This cosmic skyscape features glowing gas and dark dust clouds along side the young stars of NGC 3572 . A beautiful emission nebula and star cluster in far southern skies, the…
Messier 45: The Daughters of Atlas and Pleione
Hurtling through a cosmic dust cloud a mere 400 light-years away, the lovely Pleiades or Seven Sisters open star cluster is well-known for its striking blue reflection nebulae .…
21st Century M101
One of the last entries in Charles Messier's famous catalog, big, beautiful spiral galaxy M101 is definitely not one of the least. About 170,000 light-years across, this galaxy is…
Spiral Galaxies Spinning Super-Fast
Why are these galaxies spinning so fast? If you estimated each spiral 's mass by how much light it emits, their fast rotations should break them apart. The leading hypothesis as…
Near the Center of the Lagoon Nebula
Stars are battling gas and dust in the Lagoon Nebula but the photographer s are winning. Also known as M8, this photogenic nebula is visible even without binoculars towards the…
Daphnis and the Rings of Saturn
What's happening to the rings of Saturn? A little moon making big waves. The moon is 8-kilometer Daphnis and it is making waves in the Keeler Gap of Saturn 's rings using just its…
Inside the Flame Nebula
The Flame Nebula stands out in this optical image of the dusty, crowded star forming regions toward Orion's belt , a mere 1,400 light-years away. X-ray data from the Chandra…
The Day After Mars
October 31, 1938 was the day after Martians encountered planet Earth, and everything was calm. Reports of the invasion were revealed to be part of a Halloween radio drama, the now…
The Ghostly Veil Nebula
A ghostly visage on a cosmic scale , these remains of shocked, glowing gas haunt planet Earth's sky toward the constellation of Cygnus and form the Veil Nebula . The nebula itself…
M42: Inside 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…
Curiosity Rover Finds a Clay Cache on Mars
Why is there clay on Mars? On Earth, clay can form at the bottom of a peaceful lake when specific minerals trap water. At the pictured site on Mars , the robotic rover Curiosity…
The Space Station Crosses a Spotless Sun
Typically, the International Space Station is visible only at night. Slowly drifting across the night sky as it orbits the Earth, the International Space Station (ISS) can be seen…
Viewing discoveries from 20 November 2019 through 28 October 2019.