The flotsam
created by China's
anti-satellite test last month is on the radar screens of space debris
analysts, as well as space policy
experts.
The intentional
destruction on Jan. 11 of China's Fengyun-1C weather satellite via an anti-satellite
(ASAT) device launched by the Chinese has created a mess of fragments
fluttering through space.
The
satellite's destruction is now being viewed as the most prolific and severe fragmentation
in the course of five decades of space operations.
Lobbed into
space atop a ballistic missile, the ASAT destroyed the weather-watching satellite that had been orbiting Earth since May 10, 1999 [image].
The result was littering Earth orbit with hundreds upon hundreds of various
sizes of shrapnel.
Debris
cloud
NASA's
Orbital Debris Program Office at the Johnson Space Center is now at liberty to
discuss the characteristics and consequences of the debris cloud created by the
fragmentation of the Fengyun-1C spacecraft.
As of
today, the U.S. military's Space Surveillance Network has cataloged nearly 600
debris fragments, according to NASA's Nicholas Johnson, Chief Scientist for Orbital
Debris at the space agency's Johnson Space Center in Houston, Texas.
However, more
than 300 additional fragments are also being tracked, bringing it to a total of
more than 900 bits of clutter. "These will be cataloged in due course," Johnson
added.
"The total
count of tracked objects could go even higher. Based upon the mass of Fengyun-1C
and the conditions of the breakup, the standard NASA model for estimating the
number of objects greater than 4 inches (10 centimeters) in size predicts a
total about 950 such debris," Johnson advised SPACE.com.
Most
prolific and serious fragmentation
Johnson
said that the debris cloud extends from less than 125 miles (200 kilometers) to
more than 2,292 miles (3,850 kilometers), encompassing all of low Earth orbit.
The majority of the debris have mean altitudes of 528 miles (850 kilometers) or
greater, "which means most will be very long-lived," he said.
The number
of smaller orbital debris from this breakup is much higher than the 900-plus
being tracked. NASA estimates that the
number of debris larger than 1 centimeter is greater than 35,000 bits of
riff-raff.
"Any of
these debris has the potential for seriously disrupting or terminating the
mission of operational spacecraft in low Earth orbit," Johnson pointed out.
"This satellite breakup represents the most prolific and serious fragmentation
in the course of 50 years of space operations," he said.
Also put in
harm's way by the rain of junk from the Chinese ASAT test is the International Space
Station (ISS).
"The
collision risk between the Fengyun-1C debris cloud and the International Space
Station peaked shortly after the breakup and has been declining since. The risk
of collisions between ISS and hazardous objects in Earth orbit is now once
again dominated by the background debris population existing prior to the
breakup of Fengyun-1C," Johnson said.
Collision
of coincidences
Last year's
signing by U.S. President George W. Bush of a new U.S.
National Space Policy addressed the topic of orbital debris. The document
flagged the progress made both nationally and internationally regarding proliferation
of orbital debris over the past decade - but also underscored the worrisome
nature of space junk.
"Orbital
debris poses a risk to continued reliable use of space-based services and
operations and to the safety of persons and property in space and on Earth,"
the White House document stated. "The United States shall seek to minimize the
creation of orbital debris by government and non-government operations in space
in order to preserve the space environment for future generations."
In a
collision of coincidences, the 25th meeting of the Inter-Agency Space Debris
Coordination Committee (IADC) is slated for April 23-26 and is hosted by the
China National Space Administration. The meeting is to be held at the China
Academy of Space Technology in Beijing.
IADC is an
international governmental forum for the worldwide coordination of activities
related to the issues of human-made and natural debris in space.
Also,
reactions spurred by China's ASAT actions are sure to surface later this month
at a meeting of the Scientific and Technical Subcommittee of the United Nations
Committee on the Peaceful Uses of Outer Space in Vienna.
On the UN
agenda is the potential approval of draft Space Debris Mitigation Guidelines
that were hammered out last year.
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