Rosette Nebula


Ron Brecher

Guelph, Ontario, Canada

Moravian G3-16200 EC camera (on loan from O’Telescope), Optolong R, G and B filters, 106mm Tak FSQ-106 at f/3.6, Paramount MX, QHY5 guide camera 50mm f.l. guide scope. Acquisition with the SkyX, Manually focused. All pre-processing and processing in PixInsight. Acquired from my SkyShed in Guelph. No moon, no cloud, average transparency and poor seeing.

7x5m R, 11x5m G, and 12x5m B (total=2hr30m).

This gorgeous donut is the Rosette Nebula. It’s very large and diffuse, and contains open cluster NGC2244, which is smack dab in the middle of the Rosette. It lies about 5,200 light years away in the constellation Monoceros, and is about 50 light years across. This gives it an apparent width about three times that of the full Moon. It has an estimated mass of 10,000 times the mass of our Sun. This is a star nursery, with about 2,500 young stars estimated to be within the nebula. These stars were formed from the gas and dust in the Rosette, and are now causing the hydrogen gas in the nebula to glow, absorbing invisible infrared star light and emitting it mostly as red and blue light that we can see.

The last time I shot this object was in January 2012 – it was one of the first light images with a then-new camera and different scope. Interesting comparison!