RESCUE IN SPACE

Fortunately, space emergencies are a rare occurrence, but astronauts and space agencies need to be prepared for any eventuality that might arise

- ANDREW MAY

When Boeing's new Starliner spacecraft docked with the International Space Station (ISS) earlier this year, the two NASA astronauts on board discovered several minor faults in its propulsion system, leading to a much longer than expected stay on the ISS. This led to headlines about the astronauts being 'stranded' in space and a renewed interest in the subject of space rescue. Astronauts normally leave the ISS in the same vehicle they arrived in - and that's as true in the case of an emergency evacuation as a routine departure. Hence any problem with the spacecraft - even a relatively minor one - is a potential worry. If the problem is deemed to put the astronauts' lives at risk, then a replacement spacecraft will be sent up. That's what happened last year after a micrometeorite hit Soyuz MS-22 while it was docked to the ISS and put a hole in its external radiator. The resulting loss of coolant meant its crew couldn't use it to return to Earth, so a replacement vehicle, Soyuz MS-23, was sent up in its place.

This was the mildest form of 'space rescue', and fortunately most real-world incidents have been equally easy to deal with. But that won't always be the case, and authorities have worried about worst case scenarios since the dawn of the space age. As long ago as 1967, the United Nations agreed an international treaty that 'calls for the rendering of all possible assistance to astronauts in the event of accident, distress or emergency landing'. Here we'll look at some of the systems that have been developed to facilitate this including the Simplified Aid For EVA Rescue, or SAFER. This is a self-rescue system that astronauts can use during an extravehicular activity (EVA), or spacewalk.

ISS EMERGENCY DRILLS