Reflection Nebula IC 4601 in Scorpius

IC 4601, a reflection nebula

Dreyer description of IC 4601 in the Index Catalog (IC):

IC 4601 is a reflection nebula in the Constellation of Scorpius. The two bright stars on the right and the double star on the left are all blue giant stars of spectral class B or A. These stars undoubtedly provide the blue light reflected by the gas and dust of the nebula. The Hipparcos satellite measured a distance to one of the stars on the right as 467.27 light years, and the distance of one of the components of the double star as 121.79 light years. The double star's components have an angular separation of 13 arc seconds. Since the components have different proper motions, this pair may just be a change alignment.