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.
A Step Toward Gravitational Wave Detection
Accelerate a charge and you'll get electromagnetic radiation : light. But accelerate any mass and you'll get gravitational radiation . Light is seen all the time, but, so far, a…
Microwave Hotspots: The Oldest Structures Known
These spots are the oldest, most distant structures known. They are seen on the above two images of the microwave sky, north and south of our galaxy's equator, based on…
Moonset, Planet Earth
During the Astro-1 astronomy mission of December, 1990, Space Shuttle astronauts photographed this stunning view of the setting full moon above the Earth's limb. In the…
Close To Eros
Scroll right and fly close over asteroid Eros! This long mosaic was constructed of images returned yesterday by the NEAR Shoemaker spacecraft as it orbited to within 6.4…
The Map Of Eros
This map of Eros was constructed from a mosaic of images recorded by the NEAR Shoemaker spacecraft, currently orbiting the 40 x 14 x 14 kilometer asteroid. A simple cylindrical…
The Nebula And The Neutron Star
The lonely RX J1856.5-3754 was formed from the collapsed core of an exploding star. At a distance of 180 light-years it is the closest known neutron star. More massive than the…
Io Rotating
The surface of Io is continually changing. Jupiter's moon is the home to many powerful volcanoes so active they are effectively turning the moon inside out. The above time-lapse…
Dwarf Elliptical Galaxy NGC 205 in the Local Group
Our Milky Way Galaxy is not alone. It is part of a gathering of about 25 galaxies known as the Local Group . Members include the Great Andromeda Galaxy (M31), M32 , M33 , the…
Wild Duck Open Cluster M11
Many stars like our Sun were formed in open clusters . The above open cluster, M11 , contains thousands of stars and is just over three thousand light years distant. The stars in…
The Averted Side Of The Moon
This vintage 60-kopek stamp celebrates a dramatic achievement. On the 7th of October, 1959 (7/X/1959), the Soviet interplanetary station which has come to be called “Luna 3”…
North Pole Below
Orbiting over the north pole of planet Earth on May 5, the MODIS instrument on-board the Terra spacecraft , recorded this view of the ice cap 700 kilometers below. A radial grid…
The Farthest Explosion Yet Measured
It happened so far away that common human distance measures are inadequate to describe it. Furthermore, astronomers do not even claim to know exactly what happened. What is known…
The Space Shuttle Docking Ring
A space shuttle is again visiting the International Space Station (ISS). The STS-92 crew aboard Discovery have already delivered and installed a truss and a docking port on the…
Gemini North Images Bow Shock Near Galactic Center
What's going on near the center of our Galaxy? Glowing across the electromagnetic spectrum , the center of our Milky Way Galaxy is thought to be home to massive stars, rotating…
Dust and Gas Surrounding Star R Coronae Australis
Young star R Coronae Australis has a dusty home. The dust is so thick on the upper left of the above photograph that little light from background stars comes through. Thinner dust…
Globular Cluster Omega Centauri
Does an old, red globular cluster have any hot, blue stars? The rightmost picture, taken by the Ultraviolet Imaging Telescope in ultraviolet light, shows that indeed it does.…
The Ecliptic Plane
The Plane of the Ecliptic is well illustrated in this picture from the 1994 lunar prospecting Clementine spacecraft. Clementine's star tracker camera image reveals (from right to…
Eclipse Moon Trail
Tonight, Friday the 13th, October's big, bright, beautiful full Moon will be in the sky, rising as the sun sets. A time exposure of this evening's full Moon would show a brilliant…
HETE-2 Rides Pegasus
The Stargazer , a modified Lockheed L-1011 aircraft, soared into the skies above Kwajalein Atoll in the pacific on October 9th. A small satellite observatory known as the High…
Cassini Spacecraft Approaches Jupiter
A new spacecraft has entered the outer Solar System: Cassini . Launched in 1997 and bound for Saturn in 2004, Cassini sent back the above image last week while approaching the…
The Einstein Cross Gravitational Lens
Most galaxies have a single nucleus -- does this galaxy have four? The strange answer leads astronomers to conclude that the nucleus of the surrounding galaxy is not even visible…
A Polar Martian Dust Storm
On August 29, a large dust storm was photographed erupting out from the north polar cap of Mars . Such dust storms are not uncommon as summer advances in the north. In the above…
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…
Sputnik: Traveling Companion
Sputnik means “traveling companion”. Despite the innocuous sounding name, the launch of the Earth's first “artificial moon”, Sputnik 1 , by the Soviet Union on October 4, 1957…
Viewing discoveries from 30 October 2000 through 7 October 2000.