China's space programme is confronting one of its most serious in-orbit safety scares to date, after engineers discovered that the Shenzhou-20 return capsule, docked at the Tiangong space station, had suffered a crack in its viewport likely caused by micrometre-scale orbital debris.
The damage, confirmed in a detailed assessment by the China Manned Space Agency (CMSA), forced officials to take the unusual step of ordering the capsule home without its astronauts.
