By Eduardo BaptistaBEIJING (Reuters) -A trio of Chinese astronauts returned to Earth on Friday after getting stuck on China’s space station for more than a week due to their spacecraft sustaining debris damage, leaving China without an immediate way of bringing home the new crew in an emergency.Here is what has happened and why it is important.WHAT HAPPENED TO THE SHENZHOU-20 SPACECRAFT?The Shenzhou-20 vessel was left at the space station after China Manned Space Agency decided that a window crack was enough to make it unfit to fly.AdvertisementAdvertisementAdvertisementAdvertisementThe Shenzhou-20 crew - Chen Dong, Chen Zhongrui and Wang Jie – came home in the Shenzhou-21, which had been due to return to Earth in six months’ time.Two weeks ago, the Shenzhou-21 transported the three astronauts taking over from the Shenzhou-20 crew at the permanently inhabited space station known as Tiangong, or “Heavenly Palace”.WHAT RISKS DO THE SHENZHOU-21 CREW FACE?Tiangong is facing the unprecedented situation of having no working spacecraft to bring the Shenzhou-21 crew back to Earth in the event of an emergency.Among the trio currently stuck in Tiangong is 32-year-old Wu Fei, China’s youngest astronaut to be sent to space.AdvertisementAdvertisementAdvertisementAdvertisementChina’s space authorities and state media have so far remained silent on the vulnerability of Tiangong and its inhabitants. State broadcaster CCTV on Friday focused instead on minute-by-minute descriptions of the Shenzhou-21 spacecraft’s journey to Earth.More in WorldState news agency Xinhua said the return of the Shenzhou-20 crew “marked the first successful implementation of an alternative return procedure in the country’s space station program history”, and that the trio had set a new re …
