Messier 42, also known as NGC 1976 or the “Great Orion Nebula”, is an emission nebula in the constellation of Orion. It lies at a distance of ~1,500 light-years and has a diameter of ~30 light years. M43 is separated from M42, to the north, but is part of the same complex. It has a diameter of ~8 light-years.The top and middle images comprises 10 x Ha, OIII and SII, all 25 seconds each with 0.5m f/2.9 ASA Astrograph with FLI ML3200 camera at an altitude of 55 degrees on 14 December 2015.The fields of view of the images at the top and middle are 34’ x 23’. The top image follows the HST convention, with cloours mapped as follows: SII-Ha-OIII mapped to RGB. The middle imageshows the same frames presented using the CFHT convention, Ha-OIII-SII mapped to RGB.The bottom image comprises 6 x Luminance (300 seconds each), 0.101m f/5.4 Tele Vue refractor with FLI ML16200 camera at an altitude of 55 degrees on 28 December 2016.The field of view of the image is 132’ x 132’ (2.2 degrees square).
Hills Observatory: 1 January 2013 to 19 January 2019