IC 417 is an emission nebula and NGC 1931 is an open cluster involved in nebulosity. Together they have the common names of the Spider and the Fly.

IC 417, the Spider, is located in the large complex of red hydrogen-alpha emission nebulosity on the right side of the image. NGC 1931, the Fly, is located in the smaller nebula at lower left in the image.

Both are located in the constellation of Auriga at a distance of 7,000 to 10,000 light-years. Both nebulae have hot young stars in them that formed out of the gas and dust that comprise them. These stars then cause the nebulae to glow. In the case of the blue reflection nebula associated with NGC 1931, this is starlight reflected off of small dust particles.

NGC 1931 was discovered by William Herschel in 1793. IC 417 was included in the Index Catalog, a supplement to the New General Catalog (NGC) published by J.L.E. Dreyer in 1895 and 1908.

North is to the top in the above image.

IC 417, NGC 1931 Catalogs: IC 417: LBN 804 NGC 1931: LBN 810, Sh2-237, Cr 68 Common Name: IC 417: The Spider NGC 1931: The Fly Object Type: IC 417: Emission Nebula NGC 1931: Cluster with Nebula Magnitude: IC 417: --- NGC 1931: Cluster 10.1v Size: IC 417: 80' x 50' NGC 1931: 6' Constellation: Auriga Image Field Centered At: RA: 05h 29m 04s Dec: +34° 26' 42"