NGC 2403 can be found from different starting points. Here follows my approach for low power instruments: draw an imaginary line from Capella to Polaris. Both stars are roughly 45Â° apart. Then find the midpoint of that line. From that point, draw a line (the bisector) perpendicular to the first line, for about 15Â° in the direction of the Bearâ€™s nose (Omicron Ursae Majoris) until you run into NGC 2403.
The low power view (at x17) reminds me of the glow of a partially resolved open cluster. Two 10th mag foreground stars lie embedded in the halo of the galaxy, one on each side of the diffuse core. The stars only show up with averted vision. At x62, the galaxy appears elongated in a SSW to ENE direction. Another 11th mag foreground star appears just a few minutes away from the core of the galaxy. The three embedded stars, albeit not particular bright, interfere with the subtle glow of the distant galaxy, as if the galaxy tries to hide its appearance behind the foreground stars.
Site : Bekkevoort, Belgium ( 51Â° N )
Date : April 19, 2009
Time : around 21.00 UT
Scope : Skywatcher 102/500mm achromatic refractor
Eyepiece : Baader Hyperion Zoom at 8mm
Magnification : 63x
Filter : none
Seeing : 3/5
Transp. : 4/5
Sky brightness : 19.70 magnitudes per square arc second near zenith (SQM reading).
Sketch Orientation: N up, W right.
Digital sketch made with Corel Paint Shop Pro X2, based on a raw pencil sketch.