▁in ▁the ▁series , ▁usually ▁if ▁a ▁pro be ▁is ▁going ▁to ▁be ▁a ▁deep ▁space ▁expl orer ▁it ▁leaves ▁the ▁Earth ▁or ▁an ▁orbit ▁around ▁the ▁Earth . ▁ ▁For ▁a ▁satellite ▁or ▁space ▁pro be ▁to ▁qual ify ▁as ▁a ▁deep ▁space ▁X - ray ▁astronom er / ex plorer ▁or ▁" astr on ob ot "/ ex plorer , ▁all ▁it ▁needs ▁to ▁carry ▁ab o ard ▁is ▁an ▁X RT ▁or ▁X - ray ▁det ector ▁and ▁leave ▁Earth ' s ▁orbit . ▁ ▁U ly ss es ▁was ▁launched ▁October ▁ 6 , ▁ 1 9 9 0 , ▁and ▁reached ▁Jup iter ▁for ▁its ▁" gra v it ational ▁s ling shot " ▁in ▁February ▁ 1 9 9 2 . ▁It ▁passed ▁the ▁south ▁solar ▁pole ▁in ▁June ▁ 1 9 9 4 ▁and ▁crossed ▁the ▁e cli ptic ▁equ ator ▁in ▁February ▁ 1 9 9 5 . ▁The ▁solar ▁X - ray ▁and ▁cos mic ▁g amma - ray ▁burst ▁experiment ▁( GR B ) ▁had ▁ 3 ▁main ▁object ives : ▁study ▁and ▁monitor ▁solar ▁fl ares , ▁detect ▁and ▁local ize ▁cos mic ▁g amma - ray ▁burst s , ▁and ▁in - s itu ▁detection ▁of ▁J ov ian ▁aur ora e . ▁U ly ss es ▁was ▁the ▁first ▁satellite ▁carrying ▁a ▁g amma ▁burst ▁det ector ▁which ▁went ▁outside ▁the ▁orbit ▁of ▁Mars . ▁The ▁hard ▁X - ray ▁detect ors ▁operated ▁in ▁the ▁range ▁ 1 5 –