The Leonid Meteor Shower
The Leonid Meteor Shower will likely reach its peak in the early hours this Monday morning. Though the Moon will be bright, Leo, the shower's radiant point, will be well above the eastern horizon from Western North America and the Pacific region ...
Uranus: The Tilted Planet
Uranus is the third largest planet after Jupiter and Saturn. This picture was snapped by the Voyager 2 spacecraft in 1986 - the only spacecraft ever to visit Uranus. Uranus has many moons and a ring system. Uranus is composed mostly of rock and ...
Irregular Galaxy Sextans A
Grand spiral galaxies often seem to get all the glory. Their newly formed, bright, blue star clusters found along beautiful, symmetric spiral arms are guaranteed to attract attention. But small irregular galaxies form stars too, like this lovely, ...
Mars: A Sheer Close-up
As the Mars Global Surveyor spacecraft maneuvers toward its final mapping orbit, its cameras have been producing some sharp views of Mars. At a resolution of better than 30 feet per pixel, this image of a portion of the immense canyon, Valles ...
El Ni?o Earth
Ni?o is a temporary global climate change resulting from unusually warm water in the central Pacific Ocean. El Ni?o can cause unusual or severe weather for some locations over the next few months. Warm water is shown in white in the above ...
The Annotated Galactic Center
The sky toward the center of our Galaxy is filled with a wide variety of celestial wonders. Most are visible with only binoculars. Constellations of nearby stars include Sagittarius, Libra, Scorpius, Scutum, and Ophiuchus. Nebulae include ...
Dark Volcano Active on Io
The surface of Io is changing even as we watch. The inset frame of Jupiter's most active moon was taken by the robot spacecraft Galileo in April. Just last month the larger image was taken. The new large black spot reveals that a volcano named ...
Surveyor Slides
"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 sampling experiments, ...
Aristarchus' Unbelievable Discoveries
Here lived one of the greatest thinkers in human history. Aristarchus lived on the Greek island of Samos, a small island in the center of the above picture that can be identified with a good map. Aristarchus, who lived from 310 BC to 230 BC, ...
Evidence for Frame Dragging Black Holes
Gravity can do more than floor you. According to recent measurements of a star system thought to contain a black hole, it can spin you too. This effect, called frame-dragging, is most prominent near massive, fast spinning objects. Now, a team ...
