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.
Messier 109
Beautiful barred spiral galaxy M109 , 109th entry in Charles Messier's famous catalog of bright Nebulae and Star Clusters , is found just below the Big Dipper's bowl in the…
Red Sprite Lightning with Aurora
What's that in the sky? It is a rarely seen form of lightning confirmed only about 25 years ago: a red sprite . Recent research has shown that following a powerful positive…
The Red Rectangle Nebula from Hubble
How was the unusual Red Rectangle nebula created? At the nebula's center is an aging binary star system that surely powers the nebula but does not, as yet, explain its colors. The…
Blue Sun Bursting
Our Sun is not a giant blueberry. Our Sun can be made to appear similar to the diminutive fruit , however, by imaging it in a specific color of extreme violet light called CaK…
Earth's Richat Structure
What on Earth is that? The Richat Structure in the Sahara Desert of Mauritania is easily visible from space because it is nearly 50 kilometers across. Once thought to be an impact…
Comet PanSTARRS Anti-Tail
Once the famous sunset comet , PanSTARRS (C/2011 L4) is now visible all night from much of the northern hemisphere, bound for the outer solar system as it climbs high above the…
The Waterfall and the World at Night
Above this boreal landscape , the arc of the Milky Way and shimmering aurorae flow through the night. Like an echo, below them lies Iceland's spectacular Godafoss , the Waterfall…
Four X-class Flares
Swinging around the Sun's eastern limb on Monday, a group of sunspots labeled active region AR1748 has produced the first four X-class solar flares of 2013 in less than 48 hours.…
Kepler's Supernova Remnant in X-Rays
What caused this mess? Some type of star exploded to create the unusually shaped nebula known as Kepler's supernova remnant , but which type? Light from the stellar explosion that…
Galaxy Collisions: Simulation vs Observations
What happens when two galaxies collide? Although it may take over a billion years, such titanic clashes are quite common. Since galaxies are mostly empty space, no internal stars…
Partial Solar Eclipse with Airplane
It was just eight minutes after sunrise, last week, and already there were four things in front of the Sun. The largest and most notable was Earth's Moon, obscuring a big chunk of…
Clouds, Birds, Moon, Venus
Sometimes the sky above can become quite a show. In early September of 2010, for example, the Moon and Venus converged , creating quite a sight by itself for sky enthusiasts…
Cape York Annular Eclipse
This week the shadow of the New Moon fell on planet Earth , crossing Queensland's Cape York in northern Australia ... for the second time in six months. On the morning of May 10,…
Messier 77
Face-on spiral galaxy M77 lies a mere 47 million light-years away toward the aquatic constellation Cetus . At that estimated distance, the gorgeous island universe is about 100…
Ring of Fire over Monument Valley
As the New Moon continues this season's celestial shadow play, an annular solar eclipse track begins in western Australia at 22:30 UT on May 9 -- near sunrise on May 10 local time…
Earth's Major Telescopes Investigate GRB 130427A
A tremendous explosion has occurred in the nearby universe and major telescopes across Earth and space are investigating. Dubbed GRB 130427A, the gamma-ray burst was first…
Galaxy Cove Vista
To see a vista like this takes patience, hiking, and a camera. Patience was needed in searching out just the right place and waiting for just the right time. A short hike was…
Tails of Comet Lemmon
What caused the interestingly intricate tails that Comet Lemmon displayed earlier this year? First of all, just about every comet that nears the Sun displays two tails: a dust…
A Supercell Thunderstorm Cloud Over Montana
Is that a spaceship or a cloud? Although it may seem like an alien mothership , it's actually a impressive thunderstorm cloud called a supercell . Such colossal storm systems…
Hungarian Spring Eclipse
Last week, as the Sun set a Full Moon rose over the springtime landscape of Tihany, Hungary on the northern shores of Lake Balaton . As it climbed into the clear sky, the Moon…
Horsehead: A Wider View
Combined image data from the massive, ground-based VISTA telescope and the Hubble Space Telescope was used to create this wide perspective of the interstellar landscape…
Saturn Hurricane
Acquiring its first sunlit views of far northern Saturn late last year , the Cassini spacecraft's narrow-angle camera recorded this stunning image of the vortex at the ringed…
Omega Centauri: The Brightest Globular Cluster
This huge ball of stars predates our Sun. Long before humankind evolved, before dinosaurs roamed , and even before our Earth existed, ancient globs of stars condensed and orbited…
Humanity Explores the Solar System
What spacecraft is humanity currently using to explore our Solar System ? Presently, every inner planet has at least one robotic explorer , while several others are monitoring our…
Viewing discoveries from 23 May 2013 through 30 April 2013.