February 27, 2009
‘Space Junk’ From US Satellite Destruction Gone
The head of the Pentagon's Strategic Command said on Friday that no debris remains in space after last year's U.S. destruction of an errant spy satellite loaded with toxic hydrazine fuel, Reuters reported.
Air Force Gen. Kevin Chilton, the command's chief, said some of the debris caused when China used a ground-based ballistic missile to destroy one of its defunct weather satellites will stay in orbit for another 80 or 90 years, so there was no reason for concern over the U.S. operation.
Chilton told a symposium on air warfare hosted by the U.S. Air Force Association in Orlando, Florida, on Thursday that every bit of debris created by last year's U.S. intercept has de-orbited.
In February of last year, U.S. military used a ship-launched Raytheon Co Standard Missile-3 missile to destroy a crippled National Reconnaissance Office satellite "” blowing the satellite apart at an altitude of about 130 miles.
Many analysts interpreted the intercept as a demonstration of U.S. capabilities in response to a Chinese anti-satellite test a year earlier.
The Chinese satellite had been in polar orbit at an altitude of about 537 miles. Experts say it will take longer for the debris to re-enter the earth's atmosphere since it was higher up in space.
The more than 800 or so commercial and military satellites estimated to be operating in space as well as the International Space Station could be effected by the amount of space junk floating around outside Earth's atmosphere.
Some 2,200 pieces of orbiting junk created by the Chinese anti-satellite demonstration in January 2007 are currently being tracked by the Strategic Command, which coordinates U.S. military operations in space.
The last bits of debris from the U.S. intercept, which had been codenamed Burned Frost, de-orbited as early as last July or August, according to Chilton.
Since last year, a space operations center at Vandenberg Air Force Base, California, has been tracking fewer than 3,000 pieces of debris from the U.S. intercept, each one smaller than a football, the U.S. Defense Department said.
The Pentagon stated there were no reports of debris landing on Earth after the U.S. operation and it was unlikely any would remain intact after re-entering the atmosphere.
However, the orbiting debris problem has worsened, with some 18,000 bits now being tracked by the United States, Chilton said.
A non-operational Russian military communications satellite collided on February 10 with a commercial U.S. satellite that was part of the Iridium global communications network.
Chilton said the collision highlighted a need for more investment in sensors that could help keep track of debris and improve U.S. space situational awareness.
Image Caption: A Beehive of Satellites - The launch of the first artificial satellite by the then Soviet Union in 1957 marked the beginning of the utilization of space for science and commercial activity. During the Cold War, space was a prime area of competition between the Soviet Union and the U.S. In 1964 the first TV satellite was launched into a geostationary orbit to transmit the Olympic games from Tokyo. Later, Russian launch activities declined while other nations set up their own space programs. Thus, the number of objects in Earth orbit has increased steadily -- by 200 per year on average. The debris objects shown in the images are an artist's impression based on actual density data. However, the debris objects are shown at an exaggerated size to make them visible at the scale shown. (ESA)
On the Net: