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.
NGC 2346: A Butterfly-Shaped Planetary Nebula
It may look like a butterfly, but it's bigger than our Solar System . NGC 2346 is a planetary nebula made of gas and dust that has evolved into a familiar shape . At the heart of…
Eta Carinae in X-Rays
Eta Carinae is the one of the most luminous star systems in our Galaxy , radiating millions of times more power than our Sun . Eta Carinae is also one of the strangest star…
Triton: Neptune's Largest Moon
One hundred and fifty three years ago, on October 10th, 1846, William Lassell was observing the newly discovered planet Neptune . He was attempting to confirm his observation,…
The Frothy Milky Way
Astronomers have discovered that looking at dust along the plane of our Milky Way Galaxy is a bit like looking into a frothy glass of beer. The dust between stars in our galaxy…
NGC 1365: Barred Spiral Galaxy
NGC 1365 is a giant barred spiral galaxy about 200,000 light-years in diameter and 60 million light-years distant in the southern constellation Fornax . These three recently…
The Averted Side Of The Moon
This vintage 60-kopek stamp celebrates a dramatic achievement. On October 7th, forty years ago (7/X/1959), the Soviet interplanetary station which has come to be called “Luna 3”…
Polaris: The North Star
Polaris is quite an unusual star. First, Polaris is the nearest bright star to the north spin axis of the Earth. Therefore, as the Earth turns, stars appear to rotate around…
Two Hours Before Neptune
Two hours before closest approach to Neptune in 1989, the Voyager 2 robot spacecraft snapped this picture . Clearly visible for the first time were long light-colored cirrus -type…
The 220 Mirrors of CRTF
Even the largest of modern optical telescopes are small when compared with the light gathering power of the Central Receiver Test Facility (CRTF) located in New Mexico , USA. CRTF…
Nearby Dwarf Galaxy Leo I
Leo I is a dwarf spheroidal galaxy in the Local Group of galaxies dominated by our Milky Way Galaxy and M31 . Leo I is thought to be the most distant of the eleven known small…
Phi Persei: Double Star
It's clear who is the biggest star in this binary system. Based on recent results , this artist's vision of the double star Phi Persei , 720 light years away, shows a bright,…
New Stars In 30 Doradus
Compare these matched Hubble Space Telescope views (visible-light on top; infrared on bottom) of a region in the star-forming 30 Doradus Nebula . Find the numbered arrows in the…
Massive Stars Of 30 Doradus
This gorgeous visible-light Hubble Space Telescope image shows a young cluster of massive stars at the center of the 30 Doradus Nebula . Gas and dust clouds in 30 Doradus, also…
The Crab Nebula in X-Rays
Why does the Crab Nebula still glow? In the year 1054 A.D. a supernova was observed that left a nebula that even today glows brightly in every color possible, across the entire…
Mystery Object Explained
Explorers often discover the unexpected . Such was the case when the Second Palomar Observatory Sky Survey chanced upon the unusual object circled in the above photograph . The…
Our Galaxy in Stars, Gas, and Dust
The disk of our Milky Way Galaxy is home to hot nebulae, cold dust, and billions of stars. The red nebulae visible in the above contrast-enhanced picture are primarily emission…
M83: A Barred Spiral Galaxy
M83 is a bright spiral galaxy that can be found with a small telescope in the constellation of Hydra . It takes light about 15 million years to reach us from M83 . M83 is quite a…
Twistin' By The Lagoon
The awesome spectacle of starbirth produces extreme stellar winds and intense energetic starlight -- bombarding dusty molecular clouds inside the Lagoon Nebula ( M8 ). At least…
Cometary Globules In Orion
Intense ultraviolet light from massive, hot stars in the Orion region has sculpted and compressed clouds of dust and gas in to distinctively shaped Cometary Globules . Seen in…
Equinox and Eruptive Prominence
Today, the Sun crosses the celestial equator and seasons change from Summer to Fall in the north and Winter to Spring in the southern hemisphere. Defined by the Sun's position in…
Halos Around the Ring Nebula
What's happened to the Ring Nebula? The familiar Ring that can be seen with a small back-yard telescope takes on a new look when viewed in dim light. The above recently-released,…
The Quintuplet Star Cluster
Bright clusters of stars form and disperse near the center of our Galaxy . Four million years ago the Quintuplet Cluster, pictured above , formed and is now slowly dispersing. The…
Io in True Color
The strangest moon in the Solar System is bright yellow. This recently released picture , showing Io's true colors, was taken in July by the Galileo spacecraft currently orbiting…
Interstellar Dust-Bunnies of NGC 891
What is going on in NGC 891 ? This galaxy appeared previously to be very similar to our own Milky Way Galaxy : a spiral galaxy seen nearly edge-on . However, recent…
Viewing discoveries from 12 October 1999 through 19 September 1999.