IC 2118 Witch Head Nebula is an ancient supernova remnant or gas cloud which is located in the constellation of Eridanus and is illuminated by nearby supergiant Rigel in Orion. The IC 2118 lies 900 light-years away from Earth, in the Eridanus constellation. Its dust particles reflect blue light better than red; hence the Witch Head blue color. The Witch Head Nebula glows mainly by light reflected from Rigel. The same physical process makes the Earth's daytime sky to appear blue. The IC 2118 lies at 2.6° to the west of Rigel.