A newly discovered large asteroid will miss the Earth by a cosmic whisker this month, according to astronomers at the Minor Planet Center of the Smithsonian Astrophysical Observatory in Cambridge, Mass.
"If an object of this [size] class did hit the Earth, it would be devastating," said Brian G. Marsden, an astronomer at the center. "Think about all the objects passing by we don't know about. It's a random event to find one of these things."
The asteroid, known as 1996 JG, was discovered May 8 by astronomer Robert H. McNaught of the Siding Spring Observatory in New South Wales, Australia. McNaught found the object on photographic images taken by astronomer Michael Drinkwater with the 1.2-meter U.K. Schmidt telescope.
When discovered, the asteroid was about 18 million miles from Earth. Today, it's about 8 million miles away. When it makes its closest approach May 25, the asteroid will pass within 1.9 million miles of Earth, according to orbital calculations done by Gareth V. Williams, an astronomer at the Minor Planet Center.
The asteroid is forecast to reach 12.3 magnitude--too dim to be seen with the naked eye but possibly visible with an 8-inch telescope in very dark skies with a clear southern horizon.
Marsden said the asteroid could be as large as three-quarters of a mile in diameter.