About image NGC 457 is an open cluster in the constellation of Cassiopeia. Because of its particular shape it is also called "the Owl cluster": in fact it is dominated by two stars of sixth magnitude from which it starts a concatenation of stars that recall well the wings of a bird in flight; the two brightest stars are the "eyes" of the owl. In reality, the brightest stars in the cluster would be much closer to us, and show themselves in the direction of the cluster for a perspective effect. NGC 457 is composed of about sixty stars up to the fourteenth magnitude and is about 8000 light years.
Technical data Optic Celestron C9.25 Edge HD f/10 Mount Losmandy G11 with Ovision worm and FS2 Camera Atik 4000 with Starlight Xpress filter wheel 5 positions Filters Baader RGB 50.8 unmounted Guiding system Starlight Xpress SXV-AO-LF + OAG Starlight Xpress with Lodestar Exposure details R 12x300" bin1 -20C G 12x300" bin1 -20C B 12x300" bin1 -20C Total integration 3h Acquisition Maxim, PHD2 Processing Pixinsight 1.8, Photoshop CS5 SQM-L 18.3 Location Home terrace (Rescaldina, Italy) Date 24 September 2016