▁this ▁and ▁other ▁topics . ▁ ▁Human ▁▁ ▁The ▁first ▁human ▁space fl ight ▁was ▁V ost ok ▁ 1 ▁on ▁April ▁ 1 2 , ▁ 1 9 6 1 , ▁on ▁which ▁cos mon aut ▁Y uri ▁G ag arin ▁of ▁the ▁USS R ▁made ▁one ▁orbit ▁around ▁the ▁Earth . ▁In ▁official ▁Soviet ▁documents , ▁there ▁is ▁no ▁mention ▁of ▁the ▁fact ▁that ▁G ag arin ▁par ach uted ▁the ▁final ▁seven ▁miles . ▁Currently , ▁the ▁only ▁space craft ▁regularly ▁used ▁for ▁human ▁space fl ight ▁are ▁the ▁Russian ▁So y uz ▁space craft ▁and ▁the ▁Chinese ▁Sh enz hou ▁space craft . ▁The ▁U . S . ▁Space ▁Sh utt le ▁fleet ▁operated ▁from ▁April ▁ 1 9 8 1 ▁until ▁July ▁ 2 0 1 1 . ▁Space Sh ip One ▁has ▁conducted ▁two ▁human ▁sub orb ital ▁space fl ights . ▁ ▁Sub - orb ital ▁▁ ▁On ▁a ▁sub - orb ital ▁space fl ight ▁the ▁space craft ▁reaches ▁space ▁and ▁then ▁returns ▁to ▁the ▁atmosphere ▁after ▁following ▁a ▁( prim arily ) ▁ball istic ▁traject ory . ▁This ▁is ▁usually ▁because ▁of ▁ins u fficient ▁specific ▁orb ital ▁energy , ▁in ▁which ▁case ▁a ▁sub orb ital ▁flight ▁will ▁last ▁only ▁a ▁few ▁minutes , ▁but ▁it ▁is ▁also ▁possible ▁for ▁an ▁object ▁with ▁enough ▁energy ▁for ▁an ▁orbit ▁to ▁have ▁a ▁traject ory ▁that ▁intersect s ▁the ▁Earth ' s ▁atmosphere , ▁sometimes ▁after ▁many ▁hours . ▁P ione er ▁ 1 ▁was