5 ▁from ▁ 1 9 6 6 ▁until ▁ 1 9 6 9 . ▁ ▁The ▁lun ar ▁orb iter ▁Explorer ▁ 4 9 ▁launched ▁in ▁ 1 9 7 3 ▁was ▁gravity ▁gradient ▁orient ed ▁( Z ▁axis ▁parallel ▁to ▁local ▁vertical ). ▁ ▁Long ▁D uration ▁Ex pos ure ▁Fac ility ▁( L DEF ) ▁used ▁this ▁method ▁for ▁ 3 - axis ▁stabil ization ; ▁y aw ▁about ▁the ▁vertical ▁axis ▁was ▁stabil ized . ▁ ▁An ▁example ▁of ▁gravity - gradient ▁stabil ization ▁was ▁attempted ▁during ▁NASA ' s ▁T SS - 1 ▁mission ▁in ▁July ▁ 1 9 9 2 . ▁The ▁project ▁failed ▁because ▁of ▁t ether ▁deployment ▁problems . ▁In ▁ 1 9 9 6 ▁another ▁mission , ▁T SS - 1 R , ▁was ▁attempted ▁but ▁failed ▁when ▁the ▁t ether ▁broke . ▁Just ▁prior ▁to ▁t ether ▁separation , ▁the ▁t ension ▁on ▁the ▁t ether ▁was ▁about ▁ 6 5 ▁N ▁( 1 4 . 6   l bs ). ▁ ▁See ▁also ▁Gra vity ▁grad i ometry ▁Space ▁t ether ▁T idal ▁lock ing ▁ ▁External ▁links ▁NASA ▁on ▁A TS - 2 ▁G unter ' s ▁Space ▁Page ▁on ▁A TS ▁ 2 , ▁ 4 ▁and ▁ 5 ▁A ▁new ▁kind ▁of ▁Earth ▁S ensor ▁using ▁a ▁proof ▁mass ▁on ▁a ▁ME MS ▁created ▁by ▁EP FL ▁students ▁ ▁References ▁▁ ▁Category : Space craft ▁attitude ▁control ▁Category : Space craft ▁prop ulsion ▁Category : Space craft ▁components ▁Category :