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.
ESO202-G23: Merging Galaxies
ESO202-G23 is a colorful mess. It is a collision between two galaxies taking place over hundreds of millions of years. The representative colors give astronomers some idea of what…
The Year of Distant Supernovae
Distant supernovae were among topics at the forefront of astronomy during 1998. Two independent groups raced to deploy large telescopes to scan the sky, discovering and analyzing…
Supernova 1994D and the Unexpected Universe
Far away, long ago, a star exploded. Supernova 1994D , visible as the bright spot on the lower left, occurred in the outskirts of disk galaxy NGC 4526 . Supernova 1994D was not of…
A Geminid From Gemini
The Leonid meteor shower was not the only good meteor shower this season. Earlier this month, the annual Geminids meteor shower peaked, featuring as many as 140 meteors per hour…
NEAR to Asteroid Eros
On December 23, the NEAR spacecraft flew by asteroid 433 Eros . NEAR was originally scheduled to brake and orbit Eros, but an unexpected shutdown of its main engine caused this…
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…
Gamma-Ray Quasar
The bright object in the center of the false color image above is quasar 3C279 viewed in gamma-rays , photons with more than 40 million times the energy of visible light. Like all…
Nebulae For Christmas
If our Galaxy were a Christmas tree , planetary nebulae would adorn it like colorful lighted ornaments twinkling on a cosmic scale. Glowing shrouds of gas ejected by red giant…
Mars Climate Orbiter Launches
Looking down from atop a Delta II rocket blasting skyward , solid fuel boosters fall away (left) and the Earth's limb slides into view. These pictures from the launch of the Mars…
Ring Around the Galaxy
It is difficult to hide one galaxy far behind another. The closer galaxy's gravity will act like a huge lens , pulling images of the background galaxy around both sides. This is…
Dawn of the Leonids
Many of the 1998 Leonid shower meteors were so bright they could be seen even during sunrise. The above photograph was taken near the dawn of November 16 close to Hong Kong ,…
Solstice Sun In Soft X-rays
The solstice occurs today at 8:56 PM Eastern Standard Time. At the solstice the sun reaches its most southerly position in the sky and winter begins for the Northern Hemisphere…
Edge-On Spiral Galaxy NGC 891
Is our Galaxy this thin? We believe so. The Milky Way , like NGC 891 pictured above , has the width of a typical spiral galaxy . Spirals have most of their bright stars, gas, and…
Cartwheel Of Fortune
By chance, a collision of two galaxies has created a surprisingly recognizable shape on a cosmic scale - “The Cartwheel Galaxy” . The Cartwheel is part of a group of galaxies…
TT Cygni: Carbon Star
TT Cygni is a cool red giant star with a wind. This false-color picture of TT Cyg was made using a coordinated array of millimeter wavelength radio telescopes and shows radio…
The Night Shift
For the orbiting International Space Station (ISS), the sun sets every 90 minutes . But working through the night, spacewalking astronauts can rely on artificial lighting. Here,…
3-D Mars' North Pole
This dramatic premier three-dimensional visualization of Mars' north pole is based on elevation measurements made by an orbiting laser. During the Spring and Summer of 1998 the…
Plains and Ridges on Europa
The ridges on Europa may be caused by cold water volcanoes. Europa , one of the largest moons of Jupiter , has been the source of intense scrutiny since speculation increased of…
The Hubble Deep Field South
Among the faintest objects are some of the most unusual objects. The Hubble Deep Field South was released after much anticipation earlier this month, delivering a unique view of…
Blasting Off from the Moon
How did the astronauts get back from the Moon ? The Lunar Module that landed two astronauts on the Moon actually came apart. The top part containing the astronauts carried…
Driving To The Sun
How long would it take to drive to the Sun? Brittany, age 7, and D.J., age 12, ponder this question over dinner one evening. James, also age 7, suggests taking a really fast…
High Redshift Quasars
Each red speck indicated above is a powerful quasar estimated to be over 100 times brighter than a galaxy. Yet in these Sloan Digital Sky Survey discovery images the quasars…
Assembling The International Space Station
Batteries and solar panels were included with this version of the International Space Station (ISS) but some assembly is still required . On Saturday, December 5th, the STS-88…
NGC 253: The Sculptor Galaxy
NGC 253 is not only one of the brightest spiral galaxies visible, it is also one of the dustiest . Discovered in 1783 by Caroline Herschel in the constellation of Sculptor , NGC…
Viewing discoveries from 1 January 1999 through 9 December 1998.