Agency Terms Event A Close Call
In the first maneuver of its kind,
the National Aeronautics and Space Administration had to move one
of its spacecraft recently to protect it from man-made orbital
debris.
The Terra environmental spacecraft was moved by flight
controllers at the Goddard Space Flight Center in Greenbelt, MD, to
avoid a potential collision because of a test of a Chinese
anti-satellite (A-Sat) weapon in January, according to Fox
News.
Flight controllers "briefly fired" the spacecraft's thrusters
June 22, moving it 0.8 miles after analysis predicted a seven
percent chance of collision with debris from the destroyed Chinese
satellite Fengyun 1-C the next day.
Fengyun 1-C was a defunct Chinese weather satellite orbiting at
about 528 miles up when it was destroyed January 11 by a
controversial kinetic energy A-Sat weapon. As ANN reported, analysts
feared the test would usher in an anti-satellite arms race, or was
a political ploy by the Chinese to force the Bush administration
into a weapons ban negotiation.
"This is the first real escalation in the weaponization of space
that we've seen in 20 years," said Harvard astronomer Jonathan
McDowell to The New York Times. "It ends a long period of
restraint."
"It could be a shot across the bow," agreed Theresa Hitchens,
Center for Defense Information director, a private group in
Washington tracking various military programs. "For several years,
the Russians and Chinese have been trying to push a treaty to ban
space weapons. The concept of exhibiting a hard-power capability to
bring somebody to the negotiating table is a classic cold war
technique."
Goddard's conjunction assessment manager for the NASA's Earth
science satellite constellation, Lauri Newman, said she received an
orbital debris report from the US Air Force indicating a small
piece of debris, about 15 inches long, was on a course for a
possible collision with Terra.
"We found the event on a Monday during routine analysis and did
the maneuver on (that) Friday," she said.
The cloud of debris is being monitored by the military's Space
Surveillance Network.
It is not known for certain if a collision would have occurred
had the satellite not been moved. Additional analysis showed a
collision was, indeed, still possible, Newman said.
"We got one final prediction after
we did the maneuver and that showed that it was still in the error
bands that we were showing before," she said.
When asked if the event was a close call, Newman replied, "from
what we've seen so far, yes."
Fox reports NASA will typically fire the satellite's engine
three to five times a year to compensate for normal atmospheric
drag.
Michael Krepon, cofounder of the Washington-based Henry L.
Stimson Center, a private group studying national security said the
current administration has argued a global space-weapons treaty was
unnecessary not only because the last such tests were 20 years
ago... but also because no such weapons existed, according to the
Times.
"It seems," he said, "that argument is no longer operative."