The Iris Nebula, NGC 7023

This observation was made from my heavily light polluted backyard in Winston-Salem, NC at 12:55am EDT on Saturday, September 15, 2012. After a summer of mostly cloudy weather we finally had four consecutive nights without clouds or moon to interfere with some observing. The sky, with high humidity, was bright in town as it always is in the summer time. It was 63 degrees farenheit with no wind. The elevated humidity (87%) allowed a naked eye limiting magnitude of 4.3.

You will find NGC 7023, sometimes refered to as the Iris Nebula, about three and a half degrees southwest of magnitude 3.2 Alfirk (Beta Cephei). Through my 5-inch Mak-cass (ETX-125) with direct vision, using a 19mm eyepiece at 100x, NGC 7023 appears as a uniformly bright, circular haze about two arc minutes in diameter and surrounding the 7th magnitude star HD 200775. Adding an Orion Sky Glow filter to my 24mm eyepiece, yielding a magnification of 79x, and using some averted vision, the nebula grew to almost ten minutes in diameter that was a rounded square shape. With light pollution in town, the nebula resembled a distant light seen through a fogged up window, although there was no fog visible around any other stars.

On Friday, September 12, 2012 I was out with my 10×50 Nikon binoculars and located what I thought was NGC 7023. Using the line of four stars, alpha Cephei, 6 and 7 Cephei and beta Cephei, I placed beta Cephei on the northeast edge of my six degree field-of-view. I looked for the little equalateral triangle of seventh magnitude stars with another seventh magnituge star just west of the southwest star. Having located this triangle of stars near the center of the field-of-view, I began to use averted vision to observe then. The southwestern star in this triangle was slightly bloted and did not appear stellar like the other stars. It is hard for me to believe, but I was able to detect this nebula with my 10×50 binoculars.

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