Astronomy Picture Of the Day (APOD)Triton: Neptunes Largest Moon
In October of 1846, William Lassell was observing the newly discovered planet Neptune. He was attempting to confirm his observation, made just the previous week, that Neptune had a ring. But this time he discovered that Neptune had a satellite as well.
Lunar Transit from STEREO
A million miles from planet Earth, last weekend the STEREO B spacecraft found itself in the shadow of the Moon. So, looking toward the Sun, extreme ultraviolet cameras onboard STEREO B were able to record a stunning movie of a lunar transit (aka solar eclipse), as the Moon tracked across the solar disk.
Solar Eclipse from the Moon
Parts of Saturday's (March 3) lunar eclipse will be widely visible. For example, skywatchers in Europe, Africa, and western Asia will be able to see the entire spectacle of the Moon gliding through Earth's shadow, but in eastern North America the Moon will rise already in its total eclipse phase.
Rosetta Over Mars
Panels on ESA's Rosetta spacecraft appear in the foreground of this intriguing image of Mars recorded on February 25 at a range of about 1,000 kilometers. Launched in March 2004, Rosetta...
Stars, Dust and Nebula in NGC 2170
When stars form, pandemonium reigns. A textbook case is the star forming region NGC 2170. Visible above are red glowing emission nebulas of hydrogen, blue reflection nebulas of dust, dark absorption nebulas of dust, and the stars that formed from them.
Atmospheres Detected on Two Extrasolar Planets
Do extrasolar planets have water? In an attempt to find out, the orbiting Spitzer Space Telescope made detailed observations of the atmospheres of two planets that orbit stars other than our Sun. Unfortunately, water vapor was not detected in either exoplanet.
A Rocket Debris Cloud Drifts
What's that cloud drifting in space? It's not an astronomical nebula -- those appear to stay put. Atmospheric clouds don't look like this. The answer to last week's sky mystery turned out to be orbiting and expanding debris from the upper stage of a failed Russian rocket that exploded unexpectedly.
The Far Side of the Moon
Does this moon look familiar? Possibly not, even though it is Earth's Moon. Locked in synchronous rotation, the Moon always presents its well-known near side to Earth. But from lunar orbit, Apollo astronauts also grew to know the Moon's far side.
APOD: 2007 February 24- X rays and the Eagle Nebula
The premier Chandra X-ray Observatory images of M16, the Eagle Nebula, show many bright x-ray sources in the region. Most of the x-ray sources are energetic young stars. They are seen here as colored spots superimposed on the Hubble's well-known optical view of M16's light-year long Pillars of Creation.
APOD: 2007 February 23- Dust and the Helix Nebula
Dust makes this cosmic eye look red. The eerie Spitzer Space Telescope image shows infrared radiation from the well-studied Helix Nebula (NGC 7293) a mere 700 light-years away in the constellation Aquarius.