The crew of China's Shenzhou-21 space mission have brought back a trove of valuable scientific samples, including highly anticipated artificial embryo samples, for further research into the effects of the space environment on human development. The three astronauts of China's Shenzhou-21 mission returned to Earth safely on Friday evening aboard the Shenzhou-22 crewed spaceship, wrapping up a 210-day stay in orbit that set a new record for the longest single-crew mission aboard China's space station. #China #Shenzhou21 #Shenzhou22 #space