Comets, Meteors, and Asteroids in NASA Science News

2001 * 2001 * 2001 * 2001 * 2001

May 18: A Taste for Comet Water - When Comet LINEAR broke apart last year it revealed what many scientists thought all along: Water in Earth's oceans could have come from outer space.
April 05: Was Johnny Appleseed a Comet? - A new experiment suggests that comet impacts could have sowed the seeds of life on Earth billions of years ago.
February 27: Gamma-rays from an Asteroid - Perched on the surface of asteroid 433 Eros, NASA's NEAR spacecraft is beaming back measurements of gamma-rays leaking from the space rock's dusty soil.
February 23: Apocalypse Then - A violent collision with a space rock, like the one that doomed the dinosaurs, may have also caused our planet's greatest mass extinction 250 million years ago.

2000 * 2000 * 2000 * 2000 * 2000

November 21: Leonids Galore - The art of predicting Leonid meteors officially became a science this weekend as sky watchers around the globe enjoyed three predicted episodes of shooting stars. This story includes video and some unusual pictures of Leonid fireballs.  
October 31: Trick or Treat: It's Toutatis! - NASA scientists are monitoring a large near-Earth asteroid that tumbled past our planet on the morning of Halloween 2000. Amateur astronomers can spot it for themselves in telescopes later this month and through binoculars when it passes even closer to Earth in Sept. 2004.
October 18: Weekend Meteors - On Friday the 13th of October a brilliant fireball startled stargazers in Texas and Kansas. But that was just a piece of space junk -- a real meteor shower arrives this weekend when Earth passes through a stream of debris from Halley's comet.
September 20: A Good Month for Asteroids - September has been a good month for astronomers studying Near-Earth asteroids(NEAs). No fewer than five sizable minor planets have flown past our planet since the beginning of the month, affording astronomers a close-up look at these ever-scary space rocks.
September 01: A Close Encounter with a Space Rock - This morning a half-kilometer wide asteroid is zooming past Earth barely 12 times farther from our planet than the Moon. In cosmic terms, it's a near miss, but there is absolutely no danger of a collision. Instead, the encounter offers astronomers an unusually good opportunity to study a near-Earth asteroid.
August 28: Comet Champion of the Solar System - Less than seven months after the Solar and Heliospheric Observatory registered its 100th comet discovery, amateur astronomers help SOHO double its record-setting total. Scientists think that most of SOHO's comets are fragments from the breakup of a single giant comet long ago.
August 14: The Extraordinary Geomagnetic Perseid Meteor Shower - An interplanetary shock wave from the Sun struck Earth's magnetosphere just before the peak of the Perseid meteor shower on August 12, 2000, triggering a powerful geomagnetic storm. Stargazers across Canada and the United States were treated to the rare spectacle of a meteor shower seen against the backdrop of colorful Northern Lights.
August 07: Hubble Discovers Missing Pieces of Comet LINEAR - To the surprise and delight of astronomers, NASA's Hubble Space Telescope has discovered a small armada of "mini-comets" left behind by what seemed to be a total disintegration of the explosive comet LINEAR.  
July 31: Meltdown! - Comet LINEAR continued to blow itself apart this weekend as astronomers around the world monitored the action. The comet is still bright enough to see through amateur telescopes, but it's fading fast. This story compares the breakup of comet LINEAR with another famous fragmented comet, Shoemaker-Levy 9, that collided with Jupiter six years ago.
July 11: Comet Borrelly or Bust - NASA's experimental Deep Space 1 probe --left for dead after a guidance system failure in late 1999- was revived last month in a thrilling cross-the-solar-system rescue conducted by JPL engineers. The craft set sail again on June 28, 2000, just in time for a planned rendezvous with periodic comet Borrelly in 2001. 
July 05: Here Comes Comet LINEAR - Comet 1999 LINEAR S4, which can already be seen through binoculars, is expected to become a faint naked-eye object similar in appearance to the Andromeda Nebula as it glides by the Big Dipper this month. Maximum brightness is expected on July 23, 2000.
June 20: Sugar in Space - Scientists have found a molecular cousin to table sugar in an interstellar molecular cloud. The discovery of this molecule in a cloud where new stars are forming means it is increasingly likely that chemical precursors to life are present in such clouds long before planets develop around the stars.

April 18: Moonlit Meteors - The oldest known meteor shower peaks on the morning of April 22 just four days after the Full Moon. Bright moonlight will reduce the number of shooting stars that are easy to see, but many meteor enthusiasts will be watching anyway because it's been over 3 months since the last major meteor shower.

April 06: Strangers in the Night - During an unplanned rendezvous, the Ulysses spacecraft found itself gliding though the immense tail of Comet Hyakutake, revealing that comet tails may be much longer than previously believed. Ulysses was hundreds of millions of kilometers away from Hyakutake when the unexpected encounter took place.

February 28Going Comet Wild - NASA's STARDUST spacecraft, bound for comet Wild-2, celebrated its first year in space this month. Its ambitious goal is to intercept Wild-2 in 2004, to capture tiny bits of comet dust and debris, and then return them to Earth for analysis in 2006.