Two major programs have differing uses for the same technology: space-based robots that can latch onto satellites. One program, NASA’s Restore-L, would repair and refuel the satellites. NASA plans to use the program in an effort to refuel Landsat 7, an Earth observation satellite that was launched in 1999. A similar program, DARPA’s Robotic Servicing of Geosynchronous Satellites (RSGS), would perform “house calls in space.”
These satellites would use retractable robotic arms and sensors to perform satellite maintenance—drastically improving their life span. They could also be used to help clear up space debris. Currently, faulty satellites can rarely be repaired in space, and the cost of bringing them back to Earth and then relaunching them is prohibitive.
As a space maintenance and rescue service, the program is an exciting prospect. As a satellite killer, it's a threat.
“When you talk about a major technology revolution, it comes with good and bad," said Brian Chow, a policy analyst who writes about satellites. What’s unusual about this technology is that the good and bad are identical: robotic manipulators designed to open panels and fix wiring could just as easily be used to smash sensors.
The fact that NASA has teamed up with DARPA, the U.S. defense research agency, to build these robots is telling. The robots that can refuel and repair satellites could also be used to sabotage enemy spacecraft in a war.
“The U.S. has some extremely important national security satellites … and they are very concerned about those satellites breaking down, having problems or being attacked,” said Brian Weeden, a director for the Secure World Foundation, a space security advocacy organization.
Russia has already started deploying potential satellite killers in space. Between 2013 and 2015, three satellites, described by the Russians as “space apparatus inspectors,” were launched. Their behavior is considered “odd” by the U.S. State Department: all three have tracked as being apparently dead in space, until suddenly coming alive and maneuvering.
"(It was) not acting in a manner consistent with a satellite designed to conduct safe and responsible inspection operations," said U.S. Assistant Secretary of State Dr. Yleem Poblete at a recent session of the UN Conference on Disarmament. Russia has denounced those concerns as "unfounded, slanderous accusations based on suspicions."
One way to prevent aggressive uses of servicing satellites would be to establish a consensus on “self-defense zones” around satellites, according to Chow. For instance, if a space robot ventured too close to another country’s satellite, that country would be within its rights to treat the robot as a threat—and respond accordingly.
Space is becoming a new technological battleground—and it remains to be seen how the U.S. will respond to potential new dangers in orbit.
Read more about weapons in space at Constellation of Satellites Could Help Defend Against Hypersonic Weapons: Pentagon.