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.
The Cygnus Wall of Star Formation
The North America Nebula in the sky can do what North Americans on Earth cannot -- form stars. Specifically, in analogy to the Earth-confined continent , the bright part that…
Sunset Over Gusev Crater
What would it be like to see a sunset on Mars? To help find out, the robotic rover Spirit was deployed last month to park and serenely watch the Sun dip below the distant lip of…
Noctilucent Clouds
Sometimes it's night on the ground but day in the air. As the Earth rotates to eclipse the Sun, sunset rises up from the ground. Therefore, at sunset on the ground, sunlight still…
Visitors' Galaxy Gallery
A tantalizing assortment of island universes is assembled here. From top left to bottom right are the lovely but distant galaxies M61 , NGC 4449 , NGC 4725 , NGC 5068 , NGC 5247 ,…
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…
APOD Is Ten Years Old Today
Welcome to the eleventh year of Astronomy Picture of the Day! In a decade of editing the APOD web pages , the industrious Robert Nemiroff (left) and persistent Jerry Bonnell…
Cassiopeia A Light Echoes in Infrared
Why is the image of Cassiopeia A changing? Two images of the nearby supernova remnant taken a year apart in infrared light appear to show outward motions at tremendous speeds.…
Gliese 876 System Includes Large Terrestrial Planet
Is our Earth unique? In continuing efforts to answer this question, astronomers have now discovered an Earth-like planet orbiting a distant normal star. Previously over 150…
Tornado and Rainbow Over Kansas
The scene might have been considered serene if it weren't for the tornado . Last June in Kansas , storm chaser Eric Nguyen photographed this budding twister in a different light…
M2-9: Wings of a Butterfly Nebula
Are stars better appreciated for their art after they die? Actually, stars usually create their most artistic displays as they die. In the case of low-mass stars like our Sun and…
Earth at Twilight
No sudden, sharp boundary marks the passage of day into night in this gorgeous view of ocean and clouds over our fair planet Earth . Instead, the shadow line or terminator is…
Titan's Cryovolcano
Investigators suspect the domed feature detailed above is an ice volcano, or cryovolcano, seen in infrared light through the hazy atmosphere on Saturn's moon Titan . Since Titan's…
Venus Returns to the Evening Sky
This serene image of boats moored in the harbor of l'le-Tudy, Bretagne, France was taken on June 1st, about an hour after sunset. It also features Venus , third brightest…
Rampaging Supernova Remnant N63A
What has this supernova left behind? As little as 2,000 years ago, light from a massive stellar explosion in the Large Magellanic Cloud (LMC) first reached planet Earth. The LMC…
Galaxies in View
Galaxies abound in this cosmic scene , a well chosen telescopic view toward the northern constellation of Ursa Major . Most noticeable are the striking pair of spiral galaxies -…
Saturn: Dirty Rings and a Clean Moon
Eating surface ice from Enceladus might be healthier than eating ice from Saturn's rings -- it certainly appears cleaner. From their apparent densities and reflectance properties,…
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…
First U.S. Spacewalk
In 1965, forty years ago on June 3rd, astronaut Edward White made the first U.S. spacewalk . Tethered to his Gemini IV capsule, White is pictured above holding a compressed gas…
M27: The Dumbbell Nebula
The first hint of what will become of our Sun was discovered inadvertently in 1764 . At that time, Charles Messier was compiling a list of diffuse objects not to be confused with…
Sculpting the South Pillar
Eta Carinae , one of the most massive and unstable stars in the Milky Way Galaxy, has a profound effect on its environment. Found in the the South Pillar region of the Carina…
White Dwarf Star Spiral
About 1,600 light-years away, in a binary star system fondly known as J0806 , two dense white dwarf stars orbit each other once every 321 seconds . Interpreting x-ray data from…
The Trifid Nebula from CFHT
Unspeakable beauty and unimaginable bedlam can be found together in the Trifid Nebula . Also known as M20, this photogenic nebula is visible with good binoculars towards the…
A Great White Spot on Rhea
What caused this great white spot on the surface of Saturn's moon Rhea? The spot was first noticed last year by the robot Cassini spacecraft now orbiting Saturn . Cassini's flyby…
The Sagittarius Dwarf Tidal Stream
Is our Milky Way Galaxy out to lunch? Recent wide field images and analyses now indicate that our home galaxy is actually still in the process of devouring one of its closer…
Viewing discoveries from 21 June 2005 through 29 May 2005.