美国东部时间2015年12月21日,特拉斯创始人马斯克旗下的太空探索技术公司Space X成功发射“猎鹰-9”多级火箭,并回收一级火箭部分。这是人类在成功发射卫星的情况下,首次实现一级火箭回收,是航天史上具有里程碑意义的伟大事件。 On December 21, 2015, Space X, the space exploration technology company owned by Atlas founder Musk, successfully launched the Falcon -9 multi-stage rockets and recovered the first stage rockets. This is the first time that a mankind has achieved a level of recovery of rockets with the successful launch of satellites. This is a landmark event in the history of spaceflight.