Astronomy Picture Of the Day (APOD)Antares and Rho Ophiuchi
Why is the sky near Antares and Rho Ophiuchi so colorful? The colors result from a mixture of objects and processes. Fine dust illuminated from the front by starlight produces blue reflection nebulae. Gaseous clouds whose atoms are excited by ultraviolet starlight produce reddish emission nebulae. Backlit dust clouds block starlight and so appear dark.
Arcing toward a fiery fate, this Sungrazer comet was recorded by the SOHO spacecraft's Large Angle Spectrometric COronagraph (LASCO) on Dec. 23rd, 1996. LASCO uses an occulting disk, partially visible at the lower...
An Aurora Before the Storm
Early April brought some of the most intense auroral storms this decade. An aurora on April 6 was reported to be the largest visible on Earth since 1989, and was seen throughout Europe and much of northern North America.
The Near Infrared Sky
Was this picture taken from outside our Galaxy? No, it is a composite taken from Earth orbit, well inside our Milky Way Galaxy. In light just a little too red for human eyes...
The Far Infrared Sky
Three major sources contribute to the far-infrared sky: our Solar System, our Galaxy, and our Universe. The above recently released image, in representative colors, is the highest resolution projection yet created of the entire far-infrared sky (60 - 240 microns) created from years of observations by the now-defunct robot spacecraft COBE.
QSO H1821 643 Indicates a Universe Filled with Hydrogen
A quasar slightly depleted of a specific color of light may indicate that our universe is filled with massive amounts of ionized hydrogen. Light from QSO H1821+643, pictured above, comes to us from about a quarter of the way across the visible universe.
A Halo Around the Moon
Have you ever seen a halo around the Moon? This fairly common sight occurs when high thin clouds containing millions of tiny ice crystals cover much of the sky. Each ice crystal acts like a miniature lens.
A Presidential Panorama of Mars
Scroll right to unfold one of the great panoramas ever taken on the surface of Mars. For best viewing, click and hold the right arrow icon at the bottom of your browser window. This image, dubbed a "presidential panorama" by the Mars Pathfinder team, shows in colorful detail the surroundings of the Sagan Memorial Station.
"Safe!" In September 1967 (during regular season play), the Surveyor 5 lander actually slid several feet while making a successful soft landing on the Moon's Mare Tranquillitatis. Equipped with television cameras and soil...
X-Ray Ring Around SN1987A
This false-color image from the Chandra X-ray Observatory reveals a one light-year diameter ring of hot, ten million degree plasma. It is one of the most detailed X-ray images of the expanding blast wave from supernova 1987A (SN1987A).