Arp 31 (IC 167)

  10-inch Newtonian, StarlightXpress MX716, 50 minutes

   Arp 31 is the first of the Integral Sign class, and is obvious by its shape.  The spiral in the southwest corner of the image is NGC 691 and the bright compact galaxy right at the top edge is NGC 694.  The Atlas notes indicate "high surface brightness irregularity 5' N".  I assume this is NGC 694.  Arp 31 was not included in the NGC but was picked up in the IC.  This image was acquired on a cold (for Texas), clear night in January.  Even in good conditions and with a 50 minute exposure, the arms of Arp 31 are quite faint.

 Atlas Image                                      Previous                         Next