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.
Fermi Epicycles: The Vela Pulsar's Path
Exploring the cosmos at extreme energies, the Fermi Gamma-ray Space Telescope orbits planet Earth every 95 minutes. By design , it rocks to the north and then to the south on…
M106 Close Up
Close to the Great Bear (Ursa Major) and surrounded by the stars of the Hunting Dogs (Canes Venatici), this celestial wonder was discovered in 1781 by the metric French astronomer…
Saturn's Moon Helene in Color
Although its colors may be subtle, Saturn's moon Helene is an enigma in any light. The moon was imaged in unprecedented detail last June as the robotic Cassini spacecraft orbiting…
Higgs Boson Explained by Cartoon
What is all this fuss about the Higgs boson? The physics community is abuzz that a fundamental particle expected by the largely successful Standard Model of particle physics may…
Aurora Over Raufarhfn
It was all lined up even without the colorful aurora exploding overhead. If you follow the apex line of the recently deployed monuments of Arctic Henge in Raufarhfn in northern…
A Dangerous Sunrise on Gliese 876d
On planet Gliese 876d, sunrises might be dangerous. Although nobody really knows what conditions are like on this close-in planet orbiting variable red dwarf star Gliese 876 , the…
Sutter's Mill Meteorite
Last Sunday's bright fireball meteor falling through skies over California and Nevada produced sonic booms over a broad area around 7:51 am. Estimates indicate the meteor was…
Jupiter and the Moons of Earth
Planet Earth has many moons . Its largest artifical moon, the International Space Station , streaks through this lovely skyview with clouds in silhouette against the fading light…
Morning, Moon, and Mercury
Last week Mercury wandered far to the west of the Sun. As the solar system's innermost planet neared its greatest elongation or greatest angle from the Sun (for this apparition…
Meteor Over Crater Lake
Did you see it? One of the more common questions during a meteor shower occurs because the time it takes for a meteor to flash is typically less than the time it takes for a head…
Rosetta Approaches Asteroid Lutetia
What would it look like to approach an asteroid in a spaceship? In 2010, ESA's robotic Rosetta spacecraft zipped past the asteroid 21 Lutetia taking data and snapping images in an…
Evaporating Blobs of the Carina Nebula
No, they are not alive -- but they are dying. The unusual blobs found in the Carina nebula , some of which are seen floating on the upper right, might best be described as…
Flowing Barchan Sand Dunes on Mars
When does Mars act like a liquid? Although liquids freeze and evaporate quickly into the thin atmosphere of Mars, persistent winds may make large sand dunes appear to flow and…
3 ATs
Despite their resemblance to R2D2 , these three are not the droids you're looking for. Instead, the enclosures house 1.8 meter Auxiliary Telescopes (ATs) at Paranal Observatory in…
M57: The Ring Nebula
Except for the rings of Saturn , the Ring Nebula (M57) is probably the most famous celestial band. Its classic appearance is understood to be due to perspective - our view from…
Discovery Departs
Climbing into cloudy skies, the Space Shuttle Orbiter Discovery (OV-103) took off from Kennedy Space Center Tuesday at 7 am local time. This time , its final departure from KSC,…
The Flight Deck of Space Shuttle Endeavour
What would it be like to fly a space shuttle? Although the last of NASA's space shuttles has now been retired, it is still fun to contemplate sitting at the controls of one of the…
Antares and Clouds
Antares is a huge star. In a class called red supergiant, Antares is about 850 times the diameter of our own Sun, 15 times more massive, and 10,000 times brighter. Antares is the…
The Eagle Nebula from Kitt Peak
From afar, the whole thing looks like an Eagle . A closer look at the Eagle Nebula , however, shows the bright region is actually a window into the center of a larger dark shell…
Fata Morgana: A Possibly Titanic Mirage
Did this mirage help sink the Titanic? The optical phenomenon called Fata Morgana can make strange shapes or a false wall of water appear above a watery horizon. When conditions…
Six Moons of Saturn
How many moons does Saturn have? So far 62 have been discovered , the smallest only a fraction of a kilometer across. Six of its largest satellites can be seen here, though, in a…
A Dust Devil of Mars
It was late in the northern martian spring when the HiRISE camera onboard the Mars Reconnaissance Orbiter spied this local denizen . Tracking south and east (down and right)…
Yuri's Planet
On another April 12th , in 1961, Soviet cosmonaut Yuri Alexseyevich Gagarin became the first human to see planet Earth from space. Commenting on his view from orbit he reported,…
Geostationary Satellites Beyond the Alps
Why don't those stars move? Stars in the sky will typically appear to rise and set as the Earth turns. Those far to the north or south will appear to circle the pole. If you look…
Viewing discoveries from 4 May 2012 through 11 April 2012.