▁was ▁confirmed ▁that ▁the ▁system ▁is ▁triple , ▁with ▁an ▁inner ▁spect ro scop ic ▁pair ▁and ▁a ▁wider ▁visual ▁companion . ▁ ▁The ▁inner ▁pair ▁was ▁resolved ▁inter fer omet r ically ▁in ▁ 2 0 1 3 . ▁▁ σ ▁Ori ▁E ▁was ▁identified ▁as ▁hel ium - rich ▁in ▁ 1 9 5 6 , ▁having ▁variable ▁radial ▁velocity ▁in ▁ 1 9 5 9 , ▁having ▁variable ▁emission ▁features ▁in ▁ 1 9 7 4 , ▁having ▁an ▁ab norm ally ▁strong ▁magnetic ▁field ▁in ▁ 1 9 7 8 , ▁being ▁phot omet r ically ▁variable ▁in ▁ 1 9 7 7 , ▁and ▁formally ▁class ified ▁as ▁a ▁variable ▁star ▁in ▁ 1 9 7 9 . ▁ ▁In ▁ 1 9 9 6 , ▁a ▁large ▁number ▁of ▁low ▁mass ▁pre - main ▁sequence ▁stars ▁were ▁identified ▁in ▁the ▁region ▁of ▁Or ion ' s ▁B elt . ▁ ▁A ▁particular ▁close ▁grouping ▁was ▁discovered ▁to ▁lie ▁around ▁ σ ▁Or ion is . ▁ ▁A ▁large ▁number ▁of ▁brown ▁d war fs ▁were ▁found ▁in ▁the ▁same ▁area ▁and ▁at ▁the ▁same ▁distance ▁as ▁the ▁bright ▁ σ ▁Or ion is ▁stars . ▁ ▁Opt ical , ▁inf ra red , ▁and ▁x - ray ▁objects ▁in ▁the ▁cluster , ▁including ▁ 1 1 5 ▁non - members ▁lying ▁in ▁the ▁same ▁direction , ▁were ▁listed ▁in ▁the ▁May rit ▁Catalogue ▁with ▁a ▁running ▁number , ▁except ▁for ▁the ▁central ▁star ▁which ▁was ▁listed ▁simply