Three astronauts due to fly home after six months in space will have to remain there indefinitely because their ship is feared to have suffered damage. Chen Dong, Chen Zhongrui, and Wang Jie had already done the handover to a new crew on China’s Tiangong space station when they learned they wouldn’t be going anywhere, CNN reports. Their ride home may be compromised after the Shenzhou-20 spaceship they were due to return on was suspected of being hit in a collision. The delay was confirmed on Wednesday by China’s National Space Administration. What the impact was caused by, and the timeline for bringing them home remains unknown. China’s space agency said in a statement, “The impact analysis and risk assessment are underway.” China is taking strides to further its space program and has just launched its new rocket, Shenzhou-21. Chen, Chen, and Wang had taken off from the Inner Mongolia Autonomous Region in April. It comes just months after NASA astronauts Suni Williams and Butch Wilmore were finally brought home after nine months on the International Space Station in March.