  km . ▁The ▁pro be ▁continued ▁to ▁operate ▁in ▁the ▁day time ▁until ▁the ▁final ▁transmission ▁was ▁received ▁at ▁ 0 0 : 3 8 ▁U T ▁on ▁ 1 7 ▁June ▁from ▁ 7 . 5 ▁S , ▁ 7 6 . 3 ▁E ▁after ▁a ▁total ▁traverse ▁distance ▁of ▁ 1 1 , 1 0 0   km . ▁It ▁is ▁not ▁known ▁how ▁much ▁further ▁the ▁bal lo on ▁tra ve led ▁after ▁the ▁final ▁communication . ▁ ▁Hal ley ▁mission ▁ ▁After ▁their ▁enc oun ters , ▁the ▁Veg as ' ▁moth ers hips ▁were ▁redirect ed ▁by ▁Ven us ' ▁gravity ▁to ▁intercept ▁Hal ley ' s ▁Com et . ▁ ▁The ▁space craft ▁initi ated ▁its ▁encounter ▁on ▁March ▁ 7 , ▁ 1 9 8 6 ▁by ▁taking ▁ 1 0 0 ▁photos ▁of ▁the ▁com et ▁from ▁a ▁distance ▁of ▁. ▁ ▁V ega ▁ 2 ▁made ▁its ▁closest ▁approach ▁at ▁ 0 7 : 2 0 ▁U T ▁on ▁March ▁ 9 , ▁ 1 9 8 6 ▁at ▁. ▁The ▁data ▁int ensive ▁exam ination ▁of ▁the ▁com et ▁covered ▁only ▁the ▁three ▁hours ▁around ▁closest ▁approach . ▁They ▁were ▁intended ▁to ▁measure ▁the ▁physical ▁parameters ▁of ▁the ▁nucle us , ▁such ▁as ▁dimensions , ▁shape , ▁temperature ▁and ▁surface ▁properties , ▁as ▁well ▁as ▁to ▁study ▁the ▁structure ▁and ▁dynamics ▁of ▁the ▁com a , ▁the ▁gas ▁composition ▁close ▁to ▁the ▁nucle us , ▁the ▁dust ▁particles ' ▁composition ▁and ▁mass