Phi1 and Phi2 Orionis together form an optical double - a pair of stars that appear close together in the sky due entirely to their alignment relative to Earth. In fact Phi2 is far closer to the Sun (at about 116 light years) than Phi1, which is nearly ten times farther away. Together with nearby Heka, the two Phi stars of Orion fall near the centre of an almost circular area of nebulosity, LBN865, whose edge extends out across the sky almost as far as Betelgeuse.


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