Shenzhou X astronauts Wang Yaping, Nie Haisheng and Zhang Xiaoguang salute at a news conference at Beijing Aerospace City on July 11, 2013, after they were released Thursday from their medical quarantine and given the medical all clear. During its 15-day journey in space starting June 11, Shenzhou X docked with the orbiting space lab Tiangong-1 twice, once through automatic operation and the other manual. The astronauts spent 12 days in Tiangong-1, where they conducted space medical experiments, technical tests and delivered a lecture to students on Earth about basic physics principles.[Photo/icpress.cn]