Elon Musk: 埃隆马斯克转发了推文： 两年前的昨天，SpaceX 向@space_station twitter.com/airandspace/st 发射了其首次载人航天飞行……

Elon Musk retweeted:

Two years ago yesterday, SpaceX launched its first human spaceflight to the @space_station twitter.com/airandspace/st…