Will China start space race?

China's anti-satellite weapon test on 11 January could push the USA in one of two directions: towards developing its offensive and defensive capabilities in space or towards negotiating an international treaty banning space weapons.

But under the USA's new, more militaristic national space policy, released in October last year, simply ignoring the Chinese anti-satellite (ASAT) test would not seem to be an option. In its first policy update since 1996, the US government made clear it would take all threats to its space assets seriously.

Washington led condemnation of the January test, which made China the third nation after the USA and former Soviet Union to demonstrate an anti-satellite capability. The test involved the destruction of an obsolete low-orbiting Chinese weather satellite by a kinetic kill vehicle launched by a medium-range ballistic missile.

Confirming the event 12 days later, and only under diplomatic pressure from concerned governments, China said the ASAT test "was not directed at any country and does not constitute a threat to any country", adding it has no intention of participating in any arms race in space.

How the USA will respond to the test is unclear. "There are two opposite possibilities," says Victoria Samson, space security analyst with the non-partisan Center for Defense Information. "The US could jump full tilt into a space weapons programme, or decide we now need a treaty banning ASATs."

China and Russia have pushed for a ban on space weapons since the early 1980s, but the USA has always opposed a treaty, arguing there are no weapons in space and therefore no need for an agreement. "There is no arms race in space and we see no signs of one emerging," undersecretary of state for arms control and international security Robert Joseph said in December.

"This may be a 'Come to Jesus' moment, telling the US to be more co-operative internationally," says Samson. She says the first chance to reopen dialogue could come at a UN meeting on space debris in Viennanext month.

Beijing's ASAT test was four decades after Washington and Moscow first developed anti-satellite weapons. The USA maintained an operational direct-ascent ASAT capability, based on nuclear-armed Thor missiles, until 1976. The former Soviet Union fielded a co-orbital ASAT system, a satellite that intercepted its target and exploded a fragmenting warhead, but it was last tested in 1982 and is unlikely to still be operational.

The US Air Force began developing an air-launched ASAT in the early 1980s, culminating in the September 1985 destruction of an obsolete satellite by a missile fired from a Boeing F-15. Launching the 5.35m (17.5ft)-long, 1,180kg (2,600lb) weapon required the F-15 to perform a steep climb at supersonic speed to a precise firing location. The Vought-developed missile then released a miniature homing vehicle that steered itself on to a collision course with the satellite.

Political and other issues killed the air-launched ASAT and efforts shifted to a US Army programme to develop a ground-launched kinetic-energy weapon called KE-ASAT, but funding for this dried up earlier this decade. In the 1990s, the USA also tested a ground-based high-power laser against a satellite, ostensibly to determine the effects on optical sensors but incidentally demonstrating its anti-satellite potential.

In recent years, the USA has favoured fielding "offensive counterspace" capabilities with temporary and reversible effects. This avoids destroying satellites and creating debris, says Samson, and recognises that the Department of Defense relies on commercial spacecraft for 80% of its satellite communications. One example is CounterCom, a mobile ground-based jamming system fielded by the USAF in 2004.

Latest USAF doctrine, meanwhile, emphasises protection of US orbital assets through improved space situational awareness and satellite redundancy, manoeuvrability and hardening. Rather than the ability to shoot down enemy satellites, the USAF is more concerned about the capability to augment or replace its own.

But while the USA does not have an operational anti-satellite capability, or any known ASAT programmes, it does have several research and development efforts involving technology relevant to space weapons. Given the political will, and sufficient funding, these could be brought together in an anti-satellite programme.

Congress will get a chance to debate the US response after the DoD presents its fiscal year 2008 budget request next month. This will seek the first overt funding for anti-satellite technology for several years, in the shape of the Missile Defense Agency's Space Test Bed programme, intended to demonstrate a space-based ballistic-missile interceptor, but which could be used against satellites.

Loren Thompson, Lexington Institute analyst, believes the US response to China's ASAT test will be "reasoned, and not particularly alarmist". He sees the test as a logical defensive step for China. "The bottom line is, we do not know what China's intentions might be, or what its capabilities are. We don't know if they can attack US satellites in higher orbits, like GPS, so this may not amount to much."

Source: Flight International