Astronomy Picture Of the Day (APOD)Volcanic Terrain on Mercury
Why are many large craters on Mercury relatively smooth inside? Recent images from the robotic MESSENGER spacecraft that flew by Mercury last October show previously uncharted regions of Mercury that have large craters with an internal smoothness similar to the maria on Earth's own Moon.
Whirlpool Galaxy Deep Field
Follow the handle of the Big Dipper away from the dipper's bowl, until you get to the handle's last bright star. Then, just slide your telescope a little south and west and you might find this stunning pair of interacting galaxies, the 51st entry in Charles Messier's famous catalog.
Hubble Floats Free
Why put observatories in space? Most telescopes are on the ground. On the ground, you can deploy a heavier telescope and fix it more easily. The trouble is that Earth-bound telescopes must look through the Earth's atmosphere.
Carina Nebula Panorama from Hubble
In one of the brightest parts of Milky Way lies a nebula where some of the oddest things occur. NGC 3372, known as the Great Nebula in Carina, is home to massive stars and changing nebula.
Apollo 12 and Surveyor 3 Stereo View
Put on your red/blue glasses and gaze into this dramatic stereo view from the surface of the Moon. The 3D scene features Apollo 12 astronaut Pete Conrad visiting the Surveyor 3 spacecraft in November of 1969. The image was carefully created from two separate pictures (AS12-48-7133, AS12-48-7134) taken on the lunar surface.
East of Antares
East of Antares, dark markings sprawl through crowded star fields toward the center of our Milky Way Galaxy. Cataloged in the early 20th century by astronomer E. E. Barnard, the obscuring interstellar dust clouds include B59, B72, B77 and B78, seen in silhouette against the starry background.
IC 4592: A Blue Horsehead
This complex of beautiful, dusty reflection nebulae lies in the constellation Scorpius along the plane of our Milky Way Galaxy. Its overall outline suggests a horsehead in profile, though it covers a much larger region than the better known Horsehead Nebula of Orion.
Above Earth Fixing Hubble
What is that astronaut doing? Fixing the Hubble Space Telescope. During the fourth servicing mission to upgrade and fix Hubble, astronaut Michael Good can be seen attached to the shuttle's robotic arm, working in an open panel of Hubble. Far below, the terminator between day and night can be seen across planet Earth.
Sagittarius and the Central Milky Way
What does the center of our Milky Way Galaxy look like? In visible light, no one knows! It is not possible to see the Galactic center in light our eyes are sensitive to because the thick dust in the plane of our Galaxy obscures it.
Moon Rays Over Thurso Castle
What's happening over that castle? While waiting for the Moon to rise last month in Thurso, Scotland, amateur astrophotographer Stewart Watt took a three minute exposure of the background stars. The above image was the surprising result.