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 194: Merging Galaxy Group
Why are stars forming in the bridge between these colliding galaxies? Usually when galaxies crash , star formation is confined to galaxy disks or tidal tail s. In Arp 194 ,…
Zooming in on Star Cluster Terzan 5
Globular clusters once ruled the Milky Way. Back in the old days, back when our Galaxy first formed, perhaps thousands of globular clusters roamed our Galaxy. Today, there are…
Four Towers and the Equinox Moon
The first Full Moon of northern spring rises behind four distant towers in this telescopic view . In an image captured from some 40 kilometers west of the city of Madrid, this…
A Symphony in Northern Winter Skies
Despite the cold, a chance to view the shimmering northern lights coaxed this skygazer onto the frozen surface of Lake Superior on the west coast of the Keweenaw Peninsula and…
Star Trails and the Equinox Sunrise
Stars trail and the Sun rises in this night and day composite panorama made on March 19. The view looks toward the eastern horizon from La Nava de Santiago, Spain. To create it, a…
Equinox on Planet Earth
Welcome to an equinox on planet Earth. Today is the first day of spring in our fair planet's northern hemisphere, fall in the southern hemisphere, with day and night nearly equal…
Abell 370: Galaxy Cluster Gravitational Lens
What are those strange arcs? While imaging the cluster of galaxies Abell 370, astronomers noticed an unusual arc. The arc wasn't understood right away -- not until better images…
Horsehead and Orion Nebulas
The dark Horsehead Nebula and the glowing Orion Nebula are contrasting cosmic vistas. Adrift 1,500 light-years away in one of the night sky's most recognizable constellations ,…
M106: A Spiral Galaxy with a Strange Center
What's happening at the center of spiral galaxy M106? A swirling disk of stars and gas, M106 's appearance is dominated by blue spiral arms and red dust lanes near the nucleus, as…
NGC 3324 in Carina
This bright cosmic cloud was sculpted by stellar winds and radiation from the hot young stars of open cluster NGC 3324. With dust clouds in silhouette against its glowing atomic…
A View Toward M101
Big, beautiful spiral galaxy M101 is one of the last entries in Charles Messier's famous catalog, but definitely not one of the least . About 170,000 light-years across, this…
Perseverance Valley Panorama
Mars exploration rover Opportunity's parting panorama from Perseverance Valley spans 360 degrees in this false color mosaic. The scene is composed of 354 individual images…
Highlights of the North Spring Sky
What can you see in the night sky this season? The featured graphic gives a few highlights for Earth 's northern hemisphere. Viewed as a clock face centered at the bottom, early…
Touchdown on Asteroid Ryugu
Last month, humanity bounced a robot off an asteroid. The main reason was to collect a surface sample. Despite concern over finding a safely reboundable touchdown spot, Japan's…
The Central Magnetic Field of the Cigar Galaxy
Are galaxies giant magnets? Yes, but the magnetic fields in galaxies are typically much weaker than on Earth's surface, as well as more complex and harder to measure. Recently,…
Moonrise Through Mauna Kea's Shadow
How can the Moon rise through a mountain? It cannot -- what was photographed here is a moonrise through the shadow of a large volcano . The volcano is Mauna Kea , Hawai'i , USA ,…
Crescent Enceladus
Peering from the shadows, the Saturn-facing hemisphere of tantalizing inner moon Enceladus poses in this Cassini spacecraft image. North is up in the dramatic scene captured…
Stardust and Starlight in M78
Interstellar dust clouds and bright nebulae abound in the fertile constellation of Orion. One of the brightest, M78 , is near the center in this colorful telescopic view, covering…
Sharpless 249 and the Jellyfish Nebula
Normally faint and elusive, the Jellyfish Nebula is caught in this alluring telescopic field of view. The entire scene is a two panel mosaic constructed using narrowband image…
A February without Sunspots
Where have all the sunspots gone? Last month the total number of spots that crossed our Sun was ... zero . Well below of the long term monthly average, the Sun's surface has…
X-Ray Superbubbles in Galaxy NGC 3079
What created these huge galactic superbubbles? Two of these unusual bubbles , each spanning thousands of light-years , were recently discovered near the center of spiral galaxy…
Celestial Alignment over Sicilian Shore
This was a sunrise to remember. About a month ago, just before the dawn of the Sun , an impressive alignment of celestial objects was on display to the east. Pictured, brightest…
The Orion Bullets
Why are bullets of gas shooting out of the Orion Nebula? Nobody is yet sure. First discovered in 1983, each bullet is actually about the size of our Solar System , and moving at…
NGC 6302: The Butterfly Nebula
The bright clusters and nebulae of planet Earth's night sky are often named for flowers or insects . Though its wingspan covers over 3 light-years, NGC 6302 is no exception. With…
Viewing discoveries from 25 March 2019 through 2 March 2019.