ROANOKE TIMES
Copyright (c) 1996, Roanoke Times
DATE: Friday, November 29, 1996 TAG: 9611290119
SECTION: NATIONAL/INTERNATIONAL PAGE: A8 EDITION: METRO
SOURCE: THE WASHINGTON POST
Humanity will dodge a bullet from space today as an itinerant asteroid named Toutatis passes within 3.3 million miles of Earth, a close call by astronomical standards.
But in the solar system, what goes around comes around. And in the case of Toutatis, it will be back. The rocky object - three miles long, 1.5 miles wide and shaped like a sort of mutant carrot - has an orbit that brings it near Earth every four years.
In 1992, Toutatis came within about 2 million miles of Earth. On Sept. 29 in 2004, it will swoop less than 1 million miles away, only four times the distance to the moon, according to Gareth Williams of the Smithsonian Astrophysical Observatory in Cambridge, Mass.
Depending on who's doing the counting, astronomers estimate there may be 1,000 to 10,000 objects with a diameter of one-quarter mile or larger that have orbits that bring them close to Earth.
The first such ``near-Earth asteroid'' (NEA) was discovered in 1918, and, by 1982, the total had increased to 49.
The official NEA count is now 391, of which 205 cross Earth's orbit. That number keeps growing, said Lucy McFadden, a planetary scientist at the University of Maryland, because ``we now have about eight programs worldwide with telescopes scanning the skies to find those (near-Earth objects) we don't know about already.''
Toutatis was discovered in 1989 by French astronomers and named after an ancient Gallic deity. It is not among the largest of the known NEAs: A few are 4 or 5 miles in diameter. But it is ``one of the strangest objects in the solar system,'' according to Steven J. Ostro of NASA's Jet Propulsion Laboratory and R. Scott Hudson of Washington State University.
Ostro and Hudson studied the asteroid in detail during its 1992 appearance, and discerned not only its highly irregular shape, but its peculiar tumbling motion. Their radio telescope images - approximately 100 times more detailed than any taken previously - show that Toutatis is made up of two large lobes of material joined by a narrow isthmus, suggesting that it may have been formed when two objects collided. That, the scientists speculate, might account for its screwball motion: Toutatis rotates around its long axis every 5.41 days, and around a shorter axis every 7.35 days.
LENGTH: Short : 49 linesby CNB