NGC 2237-46 - Rosette Nebula

NGC 2237-46 is a large area of star formation, clustering, and gas, called the Rosette Nebula. NGC 2244 is the designation of the galactic star cluster at the image's center, where the nebula already has condensed into stars and has thus been "hollowed out". It is surrounded by the red glow of excited hydrogen. This is one of many sites in the Milky Way where "Bok Globules" can be found. These are small, dark, and usually spherical condensations of matter which contain young protostars. The Rosette Nebula and its attendant star cluster lie at a distance of about 6.000 light years and the nebula has a true diameter of about 160 light years, one of the largest galactic nebulae known.

Northern Monoceros, standard lens photograph.
Part of NGC 2237-46 - Rosette Nebula, Newtonian photograph.

Exposure Data

Instrument: JSO 4.9" f/3.8 Wright-Newtonian
F/stop: 4.9
Exposure: 10 x 20 min + 1 min
Camera: QHY8pro
Offset/Gain/Temp: 111 / 50% / -30°C
Date: February 1, 2011
Exposure start: 20:40 MEZ
Location: Steyersberger Schwaig, Lower Austria
Conditions: Visual limiting magnitude 6.2 mag, SQM-L sky brightness 21.2 mag/arcsec², seeing ?, temperature -7°C, slight wind, no dew
Autoguider: Meade Pictor 216 XT, max. error: 2" (RA) / 1" (Dec)
Enhancement: Basic data reduction, combine, logarithmic curves, background flattening, color correction, local contrast enhancement, star size reduction, dynamic range extension, noise filtering
Notes: Image taken during a superb night at the Steyerberger Schwaig. Nearby light pollution caused by the Semmering ski resort degraded the first few exposures.