China space station’s giant robotic arm sparks concerns in US
- Device could be ‘used in a future system for grappling other satellites’, head of US Space Command says
- 10-metre-long arm attached to the core module of the Tiangong space station is capable of lifting objects weighing up to 20 tonnes
Chinese scientists say the 10-metre-long device, which is capable of lifting objects weighing up to 20 tonnes and can move around on the outside of the station, will be used to grab incoming spacecraft as they approach and help them to dock.
While the concept is not new – China has launched several scavenger satellites fitted with robotic arms to gather and steer space debris so it burns up in the Earth’s atmosphere – not everyone in the US is convinced its purpose is wholly benign.
James Dickinson, commander of the US Space Command, told a Congress hearing last month that the technology “could be used in a future system for grappling other satellites” and was therefore a concern to the US military.
“One notable object is the Shijian-17, a Chinese satellite with a robotic arm,” he said, adding that its ability to potentially take down US probes was a “pacing challenge” in the space domain.
The China Academy of Space Technology, which developed and operates Shijian-17, said at the time of its launch in 2016 that its mission was to test “high-orbit space debris observation technologies”.
However, the Centre for Strategic and International Studies, a Washington-based think tank, said in March that the satellite had over the years made a number of “unusual manoeuvres” and varied its position in relation to other satellites while in geostationary orbit above the Earth.
“The key question is when it is used by the Chinese and what is its actual purpose,” he said.
Dickinson told Congress that in the event of a war, the combatants would spend the opening minutes trying to disable their enemy’s communication tools, like America’s GPS.
China had developed “a broad complement of jamming and cyberspace capabilities, directed energy weapons, on-orbit capabilities, and ground-based anti satellite missiles” that could block or damage US satellite systems, he said.
But Song Zhongping, a military commentator in Hong Kong, said Dickinson was playing up the China threat to justify a bigger budget and that the removal of space debris removal was an important issue.
“If China makes a breakthrough in debris removal, it will be welcomed internationally,” he said.
In a 2016 white paper, Beijing said dealing with space debris – including monitoring, early warning and emergency response – was one of its 10 major tasks for the following five years.
Several methods for clearing space junk – from gathering it up with robotic arms and nets to obliterating it with lasers – have been considered and tested, but near space, especially low Earth orbit, remains littered with man-made floating rubbish.
Nasa, the European Space Agency and the Japan Aerospace Exploration Agency have all announced space debris removal projects and launched several experimental spacecraft.
Wang Wei, head of research and development at the China Aerospace Science and Technology Corporation, said it was a challenge for all nations involved in space exploration.
“The removal of space debris is an important issue that present and future space missions must face,” he said.
“The development of this technology is necessary to protect space assets, maintain space security and resources for mankind.”