Astronomy Picture Of the Day (APOD)Fire on Earth
Sometimes, regions of planet Earth can be seen lit up with fire. Since fire is the rapid acquisition of oxygen, and since oxygen is a key indicator of life, fire on any planet would be an indicator of life on that planet.
A 2000 Leonid Through Orion
The Leonid Meteor Shower this year could be described as good but not great. During November 17 and 18 the Earth crossed through several streams of sand-sized grit left orbiting the Sun by Comet Tempel-Tuttle. Several distinct peaks in meteor activity were reported, with
Our Dusty Universe
What's black & white and red all over? Add our universe to this list. Adrift in a vast sea of darkness are not only familiar bright stars but dust that glows predominantly in far-infrared light.
Jupiter And Family
This composite image features classic portraits of members of one of the Solar System's most prominent families - Jupiter and its four large "Galilean" moons. Starting from the top the moons are Io, Europa, Ganymede, and Callisto. The top-to-bottom order is also the order of increasing distance from Jupiter.
Such beautiful things begin as grains of sand. Locked in an oyster a granule grows into an iridescent pearl, lustrous and lovely to behold. While hurtling through the atmosphere at 70 kilometers per second, a cosmic sand grain becomes an awe-inspiring meteor, its transient beauty displayed for any who care to watch.
A Daytime Fireball in 1944
While stationed in central Africa in December 1944, Norman Appleton witnessed a meteor so bright he remembered it his entire life. Right before his eyes a tremendous smoking fireball streaked across the daytime sky. Years later, as an accomplished member of the Guild of Aviation Artists, he recorded his memories in the above painting.
Coronal Rain, Solar Storm
In this picture, the Sun's surface is quite dark. A frame from a movie recorded on November 9th by the orbiting TRACE telescope, it shows coronal loops lofted over a solar active region.
The Yardangs Of Mars
OK, fans of classic science fiction might be disappointed. The yardangs are not barsoomian warriors in a newly discovered Edgar Rice Burroughs tale of adventure and conquest on the Red Planet. In fact yardangs, geologists' term for narrow, wind-eroded ridges, are common land features in the desert regions of planet Earth.
Disorder in Stephan's Quintet
What are four closely grouped galaxies doing in this image? The grouping composes a majority of the large galaxies in Stephan's Quintet, with the fifth prominent galaxy located off the above image to the lower right.
The Lyman Alpha Forest
We live in a forest. Strewn throughout the universe are "trees" of hydrogen gas that absorb light from distant objects. These gas clouds leave numerous absorption lines in a distant quasar's spectra, together called the Lyman-alpha forest.