, ▁ 2 3 ▁minutes , ▁ 4 2 ▁seconds . ▁ ▁ST S - 5 1 - F ▁ ▁On ▁ST S - 5 1 - F / Sp ac el ab - 2 , ▁the ▁crew ▁ab o ard ▁Ch allen ger ▁launched ▁from ▁the ▁Kennedy ▁Space ▁Center , ▁Florida , ▁on ▁ 2 9 ▁July ▁ 1 9 8 5 , ▁and ▁land ed ▁at ▁Edwards ▁Air ▁Force ▁Base , ▁California , ▁on ▁ 6 ▁August ▁ 1 9 8 5 . ▁This ▁flight ▁was ▁the ▁first ▁pal let - only ▁Sp ac el ab ▁mission , ▁and ▁the ▁first ▁mission ▁to ▁operate ▁the ▁Sp ac el ab ▁Inst rument ▁Point ing ▁System ▁( IP S ). ▁It ▁carried ▁ 1 3 ▁major ▁experiments ▁in ▁astronom y , ▁ast ro physics , ▁and ▁life ▁sciences . ▁During ▁this ▁mission , ▁Mus gra ve ▁served ▁as ▁the ▁systems ▁engineer ▁during ▁launch ▁and ▁entry , ▁and ▁as ▁a ▁pilot ▁during ▁the ▁orb ital ▁operations . ▁Mission ▁duration ▁was ▁ 7 ▁days , ▁ 2 2 ▁hours , ▁ 4 5 ▁minutes , ▁ 2 6 ▁seconds . ▁ ▁ST S - 3 3 ▁ ▁On ▁ST S - 3 3 , ▁he ▁served ▁ab o ard ▁the ▁Space ▁Sh utt le ▁Disc overy , ▁which ▁launched ▁at ▁night ▁from ▁the ▁Kennedy ▁Space ▁Center , ▁Florida , ▁on ▁ 2 2 ▁November ▁ 1 9 8 9 . ▁This ▁class ified ▁mission ▁operated ▁pay loads ▁for ▁the ▁United ▁States ▁Department ▁of ▁Def ense