Astronomers have used the world's two most powerful radar telescopes to make the most detailed images ever obtained for a large asteroid in a potentially Earth-threatening orbit.

With an average diameter of about 3.5 kilometers (2 miles), 1999 JM8 is the largest of the so-called potentially hazardous asteroids ever studied in detail. Although this object can pass fairly close to Earth in celestial terms, astronomers concur that an actual encounter with Earth is not of concern in the next few centuries.

The new images, obtained with NASA's Goldstone Solar System Radar in California and the Arecibo Observatory in Puerto Rico, reveal that 1999 JM8 is a several-kilometer-wide object with a peculiar shape and an unusually slow and possibly complex spin state, said Dr. Lance Benner of NASA's Jet Propulsion Laboratory, Pasadena, CA, who led the team of astronomers. The images are available online at  http://photojournal.jpl.nasa.gov or http://echo.jpl.nasa.gov/~lance/1999JM8.html.

"It will take much more data analysis to determine the object's shape and exact rotation state," Benner said. "But just from looking at the images we can see that this nearby world is extremely peculiar. At this point we do not understand what some of the features in the images are, much less how they originated."

Mitch Battros
Producer - Earth Changes TV
http://www.earthchangesTV.com