aked ▁eye . ▁Based ▁upon ▁par alla x ▁measurements , ▁this ▁system ▁is ▁located ▁at ▁a ▁distance ▁of ▁roughly ▁ 6 4 0   light - year s ▁( 1 9 6   parse cs ) ▁from ▁Earth . ▁ ▁This ▁is ▁a ▁spect ro scop ic ▁binary ▁system , ▁which ▁means ▁that ▁the ▁presence ▁of ▁an ▁orbit ing ▁companion ▁has ▁been ▁revealed ▁by ▁radial ▁velocity ▁variations ▁in ▁the ▁spectrum ▁of ▁the ▁primary . ▁The ▁two ▁components ▁are ▁orbit ing ▁each ▁other ▁with ▁a ▁period ▁of ▁ 1 4   days ▁at ▁a ▁high ▁orb ital ▁ecc ent ric ity ▁of ▁ 0 . 5 5 . ▁The ▁secondary ▁component ▁has ▁about ▁ 6 – 1 3 % ▁of ▁the ▁primary ' s ▁mass ▁and ▁may ▁have ▁a ▁stell ar ▁classification ▁in ▁the ▁range ▁from ▁A 6   V ▁to ▁K 1   V . ▁There ▁may ▁be ▁a ▁third ▁component ▁to ▁this ▁system ▁with ▁an ▁orb ital ▁period ▁of ▁roughly ▁ 9 , 4 2 8   days ▁( 2 5 . 8 ▁years ), ▁although ▁this ▁has ▁not ▁been ▁conclus ively ▁demonstrated . ▁If ▁this ▁component ▁exists , ▁it ▁would ▁have ▁about ▁ 5 1 – 1 3 9 % ▁of ▁the ▁primary ' s ▁mass . ▁This ▁high ▁level ▁of ▁uncertainty ▁is ▁because ▁the ▁incl ination ▁of ▁the ▁orbit ▁is ▁not ▁known . ▁ ▁The ▁primary ▁component ▁of ▁this ▁system , ▁E psilon ▁Per se i ▁A , ▁is ▁a ▁massive ▁star ▁with ▁ 1 2 – 1 6 ▁times