Astronomy Picture Of the Day (APOD)SN 1006: Pieces of the Cosmic Ray Puzzle
Research balloon flights conducted in 1912 by Austrian physicist Victor Hess revealed that the Earth was constantly bombarded by high energy radiation from space - which came to be called "Cosmic Rays". What are Cosmic Rays and where do they come from?
A Frosty Crater On Mars
In the martian southern hemisphere, autumn has arrived. As on planet Earth, the cooler temperatures bring a seasonal frost to the landscape. Of course on Mars, the surface temperatures can be really cool, reaching below minus 100 degrees C.
Palomar 13's Last Stand
Globular star cluster Palomar 13 has roamed the halo of our Milky Way Galaxy for the last 12 billion years. The apparently sparse cluster of stars just left of center in this composite color digital image, it is one of the smallest, faintest globular clusters known.
Leonids from Orbit
Here is what a meteor shower looks like from orbit. During the peak of the 1997 Leonid Meteor Shower, the MSX satellite imaged from above 29 meteors over a 48 minute period entering the Earth's atmosphere. From above, meteors create short bright streaks.
BZ Cam Bow Shock
BZ Cam is a binary star system that is not well understood. In most cataclysmic variables, matter from a normal star accumulates on the surface of the companion white dwarf star, eventually causing a nova-like flare as the material becomes hot enough to ignite nuclear fusion.
Earth at Night
This is what the Earth looks like at night. Can you find your favorite country or city? Surprisingly, city lights make this task quite possible. Human-made lights highlight particularly developed or populated areas of the Earth's surface, including the seaboards of Europe, the eastern United States, and Japan.
Leonids Above Torre de la Guaita
Last year, the 1999 Leonids Meteor Shower came to a tremendous crescendo. Observers in Europe observed a sharp peak in the number of meteors visible around 0210 UTC during the early morning hours of November 18. Meteor counts then exceeded 1000 per hour - the minimum needed to define a true meteor storm.
A High Energy Fleet
Like a fleet of futuristic starcruisers, NASA's highly successful series of High Energy Astrophysical Observatory (HEAO) spacecraft appear poised over planet Earth. Labeled A, B, and C in this vintage illustration, the spacebased telescopes were known as HEAO-1, HEAO-2, and HEAO-3 respectively.
Just last week this long lovely Leonid shower meteor arced through the night. Captured on November 17/18 by photographer Bob Yen, the meteor trail spans about 70 times the apparent diameter of the full moon in the skies above Mt. Wilson, California, USA. The Leonid's path flashes from
Cassini At Jupiter: Red Spot Movie
Everything is big on Jupiter, the solar system's reigning gas giant. For example, Jupiter's Great Red Spot is a hurricane-like storm system at least twice the diameter of planet Earth. Approaching Jupiter...