2008 APS April Meeting and HEDP/HEDLA Meeting
Volume 53, Number 5
Friday–Tuesday, April 11–15, 2008;
St. Louis, Missouri
Session X6: Space Debris
1:30 PM–3:18 PM,
Tuesday, April 15, 2008
Hyatt Regency St. Louis Riverfront (formerly Adam's Mark Hotel),
Room: Promenade D
Sponsoring
Unit:
FPS
Chair: Benn Tannenbaum, AAAS
Abstract ID: BAPS.2008.APR.X6.3
Abstract: X6.00003 : China's ASAT Weapon: Capabilities and the Potential Threat
2:42 PM–3:18 PM
Preview Abstract
Abstract
Author:
Geoffrey Forden
(MIT)
Much has been said about China's 11 January 2007 test of an anti-satellite
(ASAT) weapon but few analysts have based their comments on a scientific
determination of the weapons capabilities. This paper presents such an
analysis derived from the observed pattern of debris, as observed by NORAD
and posted on-line by NASA. It is clear that this was a direct hit-to-kill
weapon (as opposed to a fragmentation-type explosive warhead), it massed
about 600 kg, and was capable of accelerations of at least 6 Gs. It can be
inferred with a reasonable degree of confidence that it used an on-board
optical tracker, most likely operating in visible light. Furthermore, since
the closing speed between the target satellite and the interceptor was 8
km/s during the test, this weapon could be used to attack satellites at
higher altitude orbits, such as NAVSTAR/GPS and geostationary satellites
that include communications and early warning satellites. This test produced
ten times as many pieces of debris as an earlier US hit-to-kill ASAT test
which, because of their higher altitudes, will last thousands of
years---hundreds of times longer than the debris in the US test. China's
test increased the chances of some low earth orbit satellite being hit by a
piece of debris by 50{\%}, from about 12{\%} to 18{\%} each year.
Given this weapon's capabilities, it is possible to ``war game'' what an
all-out Chinese ASAT attack would look like and what responses the US could
take. (It is important to emphasize that this is a capabilities-based
exercise and not based on Chinese intentions.) If China did launch such an
attack, it could eliminate a large fraction of US military satellites in low
earth orbit including photo-reconnaissance and electronic intelligence
satellites, but not all of them, in the first 24 hours; the requirement that
the target satellites be illuminated by the sun limits the attack.
Furthermore, the US could maneuver its LEO satellites in the first hours of
the attack and greatly complicate the task of their destruction. If coupled
by attacks on China's largest radars, the US could save a number of their
LEO satellites. China would have to choose to attack either US GPS
satellites or communications satellites, but not both, since its launch
capabilities are insufficient. If it attacked the GPS constellation, it
could not prevent the US from using precision guided munitions.
To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2008.APR.X6.3