U.S. Spy Satellite, Power Gone, May Hit Earth

WASHINGTON — A disabled American spy satellite is rapidly descending and is likely to plunge to Earth by late February or early March, posing a potential danger from its debris, officials said Saturday.

Officials said that they had no control over the nonfunctioning satellite and that it was unknown where the debris might land.

“Appropriate government agencies are monitoring the situation,” Gordon Johndroe, a spokesman for the National Security Council, said in a statement. “Numerous satellites over the years have come out of orbit and fallen harmlessly. We are looking at potential options to mitigate any possible damage this satellite may cause.”

Specialists who follow spy satellite operations suspect it is an experimental imagery satellite built by Lockheed Martin and launched from Vandenberg Air Force Base in California in December 2006 aboard a Delta II rocket. Shortly after the satellite reached orbit, ground controllers lost the ability to control it and were never able to regain communication.

“It’s not necessarily dead, but deaf,” said Jonathan McDowell, an astronomer at the Harvard-Smithsonian Center for Astrophysics and an analyst for various government space programs.

It is fairly common for satellites to drop out of orbit and enter Earth’s atmosphere, but most break up before they reach the surface, Mr. McDowell said. Such incidents occur every few months, and it is often difficult to control the satellite’s trajectory or its re-entry into the atmosphere. The debris, if any survives the fiery descent, typically lands in remote areas and causes little or no harm.