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.

M27: Not A Comet
While searching the skies above 18th century France for comets, astronomer Charles Messier diligently recorded this object as number 27 on his list of things which are definitely…

Methane Rain Possible on Titan
Might it rain cold methane on Saturn's Titan? Recent analyses of measurements taken by the Huygen's probe that landed on Titan in 2005 January indicate that the atmosphere is…

The Milky Way over Utah
If sometimes it appears that the entire Milky Way Galaxy is raining down on your head, do not despair. It happens twice a day. As the Sun rises in the East, wonders of the night…

Possible Methane Lakes on Titan
Have methane lakes been discovered on Saturn's Titan? That exciting possibility was uncovered from analyses of radar images returned last week by the robotic Cassini spacecraft…

Valles Marineris: The Grand Canyon of Mars
The largest canyon in the Solar System cuts a wide swath across the face of Mars . Named Valles Marineris , the grand valley extends over 3,000 kilometers long, spans as much as…

The Swarm
What do you call a group of black holes ... a flock, a brace, a swarm? Monitoring a region around the center of our Galaxy , astronomers have indeed found evidence for a…

Four Supernova Remnants
These four panels show x-ray images of expanding cosmic debris clouds, tens of light-years across, in nearby galaxy the Large Magellanic Cloud . The supernova remnants (SNRs) are…

NGC 7331 and Beyond
Spiral galaxy NGC 7331 is often touted as an analog to our own Milky Way . About 50 million light-years distant in the northern constellation Pegasus , NGC 7331 was recognized…

Explosions from White Dwarf Star RS Oph
Spectacular explosions keep occurring in the binary star system named RS Ophiuchi . Every 20 years or so, the red giant star dumps enough hydrogen gas onto its companion white…

Jupiter's Two Largest Storms Nearly Collide
Two storms systems larger than Earth are nearly colliding right now on planet Jupiter . No one was sure what would happen, but so far both storms have survived. In the above…

The International Space Station on the Horizon
This was home. Last week, the STS-121 crew of the Space Shuttle Discovery undocked from the International Space Station (ISS) and returned to Earth. As the shuttle departed the…

The Belt of Venus over the Valley of the Moon
Although you've surely seen it, you might not have noticed it. During a cloudless twilight , just before sunrise or after sunset , part of the atmosphere above the horizon appears…

Mira: The Wonderful Star
To seventeenth century astronomers, Omicron Ceti or Mira was known as a wonderful star - a star whose brightness could change dramatically in the course of about 11 months. Modern…

Strangers on Mars
This view from the winter station of Mars Exploration Rover Spirit, looks across the rock strewn landscape of Gusev Crater . The dark boulders and distant hills are characteristic…

Constellation Construction
This lovely twilight scene , recorded last April, finds a young crescent Moon low in the west at sunset. Above it, stars shine in the darkening sky but they too are soon to drop…

Reflections on Planet Earth
Catching sight of your reflection in a store window or shiny hubcap can be entertaining and occasionally even inspire a thoughtful moment. So consider this reflective view from…

Noctilucent Clouds Over Sweden
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…

Venus Express Arrives at Venus
Humanity now has a spacecraft orbiting Venus. The robotic Venus Express spacecraft launched by the European Space Agency in 2005 November arrived at Venus in 2006 April. Venus…

The Galactic Center in Infrared
The center of our Galaxy is a busy place. In visible light , much of the Galactic Center is obscured by opaque dust . In infrared light , however, dust glows more and obscures…

Reflecting Merope
In the well known Pleiades star cluster, starlight is slowly destroying this wandering cloud of gas and dust . The star Merope lies just off the upper left edge of this picture…

The Colorful Clouds of Rho Ophiuchi
This stunning mosiac of the sky around bright stars Antares (Alpha Scorpii ) and Rho Ophiuchi reveals spectacular colors in a cosmic starscape. Near the top, Rho Ophiuchi and…

A Space Shuttle Climbs to Orbit
You are going into space. New small cameras allow anyone with a web browser to virtually ride along with the space shuttle , at times from numerous angles, as it launches into…

A Manhattan Sunset
Today, if it is clear, Manhattan will flood dramatically with sunlight just as the Sun sets precisely on the centerline of every street. Usually, the tall buildings that line the…

Crescent Rhea Occults Crescent Saturn
Soft hues, partially lit orbs, a thin trace of the ring, and slight shadows highlight this understated view of the majestic surroundings of the giant planet Saturn. Looking nearly…
Viewing discoveries from 3 August 2006 through 11 July 2006.