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.
Aurora, Stars, Meteor, Lake, Alaska
Sometimes, after your eyes adapt to the dark, a spectacular sky appears. In this case, a picturesque lake lies in front of you, beautiful green aurora flap high above you,…
Galaxy NGC 474: Cosmic Blender
What's happening to galaxy NGC 474? The multiple layers of emission appear strangely complex and unexpected given the relatively featureless appearance of the elliptical galaxy in…
Two Million Galaxies
Our universe is filled with galaxies. Galaxies -- huge conglomerations of stars , gas , dust -- and mysterious dark matter are the basic building blocks of the large-scale…
X-ray Stars of Orion
The stars of Orion shine brightly in visible light in planet Earth's night sky. The constellation harbors the closest large stellar nursery, the Great Nebula of Orion , a mere…
Starburst Cluster in NGC 3603
A mere 20,000 light-years from the Sun lies NGC 3603 , a resident of the nearby Carina spiral arm of our Milky Way Galaxy . NGC 3603 is well known to astronomers as one of the…
50th Anniversary of Sputnik: Traveling Companion
Sputnik means “traveling companion”. Despite the innocuous sounding name, the launch of planet Earth's first artificial moon, Sputnik 1 , by the Soviet Union on October 4, 1957,…
Comet Encke's Tail Ripped Off
Swinging inside the orbit of Mercury, on April 20th periodic comet Encke encountered a blast from the Sun in the form of a Coronal Mass Ejection (CME). When CMEs, enormous clouds…
Tutulemma: Solar Eclipse Analemma
If you went outside at exactly the same time every day and took a picture that included the Sun, how would the Sun appear to move? With great planning and effort, such a series of…
The Small Cloud of Magellan
Portuguese navigator Ferdinand Magellan and his crew had plenty of time to study the southern sky during the first circumnavigation of planet Earth. As a result, two celestial…
A Milky Way Band
Most bright stars in our Milky Way Galaxy reside in a disk. Since our Sun also resides in this disk, these stars appear to us as a diffuse band that circles the sky. The above…
Dawn Launch Mosaic
Shortly after sunrise on Thursday at Cape Canaveral Air Force Station, the Dawn spacecraft began its journey to the asteroid belt, arcing eastward into a blue and cloudy sky.…
A Hole in Mars Close Up
In a close-up from the HiRISE instrument onboard the Mars Reconnaissance Orbiter, this mysterious dark pit, about 150 meters across, lies on the north slope of ancient martian…
Hole in the Sun
The dark expanse below the equator of the Sun is a coronal hole -- a low density region extending above the surface where the solar magnetic field opens freely into interplanetary…
Saguaro Moon
A Full Moon rising can be a dramatic celestial sight , and Full Moons can have many names. For example, tonight's Full Moon, the one nearest the autumnal equinox in the northern…
Zodiacal Light and the False Dawn
An unusual triangle of light will be particularly bright near the eastern horizon before sunrise during the next two months for observers in Earth's northern hemisphere. Once…
A Galactic Star Forming Region in Infrared
How do stars form? To help study this complex issue, astronomers took a deep image in infrared light of an active part of our Milky Way Galaxy where star formation is rampant. In…
The Equal Night
Today, the Sun crosses the celestial equator heading south at 0951 UT . Known as the equinox, the astronomical event marks the first day of autumn in the northern hemisphere and…
Pangea Ultima: Earth in 250 Million Years?
Is this what will become of the Earth's surface? The surface of the Earth is broken up into several large plates that are slowly shifting. About 250 million years ago, the plates…
Coronet in the Southern Crown
X-rays from young stars and infrared light from stars and cosmic dust are combined in this false color image of a star-forming region in Corona Australis , the Southern Crown. The…
Northern Cygnus
Bright, hot, supergiant star Deneb lies at top center in this gorgeous skyscape . The 20 frame mosaic spans an impressive 12 degrees across the northern end of Cygnus the Swan .…
4,000 Kilometers Above Saturn's Iapetus
What does the surface of Saturn's mysterious moon Iapetus look like? To help find out, the robotic Cassini spacecraft now orbiting Saturn was sent soaring last week just 2,000…
Tungurahua Erupts
Volcano Tungurahua erupted spectacularly last year. Pictured above , molten rock so hot it glows visibly pours down the sides of the 5,000-meter high Tungurahua , while a cloud of…
Inside Victoria Crater on Mars
NASA's Opportunity rover is now inside Victoria Crater on Mars . Last week the robot rolled about 20 meters into the largest crater any Martian rover has yet encountered, the…
To Fly Free in Space
At about 100 meters from the cargo bay of the space shuttle Challenger, Bruce McCandless II was further out than anyone had ever been before. Guided by a Manned Maneuvering Unit…
Viewing discoveries from 9 October 2007 through 16 September 2007.