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flSTRONOMERS SPOT BflFFLING OBJECT IN ENORMOUS ORBIT
~ strange object that moves like a comet but looks like an asteroid vjas spotted in space by an flir Force telescope using a special camera. The object, ~ith a diameter of 5 to 10 miles, may be an unusual asteroid or a dead comet stripped of all volatile material, NASfi officials said L'Jednesday (Sept 4). This is a misfit in the grand scheme of things," Eleanor Helm, principal investigator of the Near-Earth fisteroid Tracking Program at NASfi's Jet Propulsion Laboratory, said in a statement. Scientists said nothing like it has been seen before
The object, dubbed 1996 PU, ~as spotted in data taken from an flug. 9 observation atop Mount Haleakala on Maui, Ha~aii. fi special camera attached to the telescope automatically surveys the skies for objects, asteroids and comets, ~hich could pose a hazard to Earth. fisteroids are rocky bodies that mainly orbit in the "asteroid belt" betNeen Jupiter and Mars Comets generally have volatile material streaming off No comet-like gas emissions ~ere observed from 1996 PU, even during its closest approach to the sun, supporting the argument that the object is an asteroid
Steve Pravdo, the project task manager for the asteroid tracking program, says the estimated orbit period is about 5,000 years and stretches out to between the orbits of Neptune and Pluto Most of the orbits of the asteroids are on the order of threefive years, sometimes as high as fifty years. The comet-like motion was spotted by scientist Garth Uilliams while processing the data with a computer at the Smithsonian fistrophysical Observatory in Cambridge~ Mfl.
Scientists using a 5-meter telescope at Palomar Mountain in San Diego County plan on making observations to determine the object's physical measurements and composition. JPL's special camera, installed on Maui in December 1995, uses time exposures to spot the ~- movement of objects near Earth among the thousands of celestial