Pentagon wants laser attack warnings for satellites

A few month ago the U.S. defense community was alarmed by China’s growing anti-satellite warfare (ASW) capabilities, as demonstrated in a test China conducted. The U.S. economy — and the U.S. military capabilities — are so dependent on satellites, that protecting them is becoming more of a priority. The Pentagon is developing sensors to pinpoint a ground-based laser attempting to blind one of its spy satellites. New Scientist’s Paul Marks writes that the move will be interpreted as a further step towards the militarization of space, say some experts. Pentagon officials have privately voiced concern that malfunctioning spy satellites might actually be the target of “illumination” by Chinese forces testing such technology. Last year the Space Superiority Systems Wing, a department within the U.S. Air Force responsible for developing military space technology, called on contractors to develop technologies to “sense and attribute” a laser attack, in a program called Self Awareness/Space Situation Awareness (SASSA). The SASSA system will need to sense a broad range of laser and radio wavelengths. “Such warning receivers are known and understood technology,” says Rob Hewson, editor of the journal Jane’s Air Launched Weapons. The challenge, he says, will be making the technology light enough as well as figuring out precisely where a laser beam is coming from.

This month, Lockheed Martin and Boeing revealed their SASSA proposals. In addition to detecting and identifying debilitating laser attacks, SASSA will also sense attempts to jam a satellite’s radio transmissions. The U.S. Air Force wants to fly a demonstration SASSA system aboard TacSat-5, a satellite for testing new technologies that will launch in 2011. An Air Force document (pdf) obtained by the Project On Government Oversight, describes SASSA as “crucial to enabling a full range of U.S. responses from diplomatic to military in the event of hostile action against our spacecraft.” Despite SASSA being a defensive technology, some believe it could make future conflict in space more likely. “It’s a defensive step but one that assumes an attack,” says military analyst Hewson. “It is a baby step in the preparation for fighting in space.” Fuelling fears of space-based battles are concerns over two recent satellite shootdowns. In January 2007 China destroyed a defunct weather satellite with a ballistic missile. In February 2008 the United States did likewise, although the satellite targeted was close to re-entering the atmosphere and did not leave a vast cloud of space junk in its wake. “The U.S. is becoming more vocal about protecting its satellites after China’s anti-satellite test,” says Hewson. “And the reason is that the US is uniquely vulnerable because of its massive dependence on space systems for everything from high-tech communications to satellite navigation.” Hewson says the ability to blind a spy satellite using a ground-based laser is real enough: “If you can hit the sensor with a big enough burst of energy it will blind optical sensors on a photoreconnaissance satellite. The laser technology to perform this attack has been around since the 1980s.” Andrew Brookes, an analyst at the Institute for Strategic Studies in London, doubts that the technology has already been used in anger. “I’m not saying somebody isn’t thinking about it,” he told New Scientist. “But I know of no evidence of it being used by the Chinese government.”