NGC 2244, The Rosette Nebula

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The Rosette Nebula is a collection of emission and dark nebulae in the constellation Monoceros.  This area is a region of active star birth centered on the open cluster NGC 2239, the brighter stars in the core of the nebula.  These stars formed from the dust and gas of the nebula and their radiating pressures have blown a massive bubble in the core region of the nebula about thirty light years across.  Eventually the stellar pressures of these stars and others that will form will cause the nebula to dissipate.

These young and massive O type stars are the energy source for the emission nebulosity and their pressure continues to form Bok Globules within the nebula.  Bok globules are denser clumps of dust and gas from which protostars are formed. They are revealed as dark knots and pillars in this image.  

In total, this nebula spans about a degree of our sky or two full moon widths and is about 5,500 light years distant.  This means the roughly spherical nebula is about 130 light years in diameter.

At magnitude 4.8, NGC 2239 is an open cluster visible to the naked eye and makes for a fine visual target in both binoculars and telescopes.  However the nebulosity of the Rosette is much more difficult to see visually with only separate portions of the brighter areas being visible (see annotations).  In point of fact, the Rosette Nebula region contains NGC 2237 through NGC 2239, NGC 2246 and open cluster NGC 2252 just east.  In addition, other HII regions have been cataloged as shown.  It's also cataloged as Caldwell 49 (the nebula itself) and Caldwell 50 (the central open cluster).

Date:  1/28/2006

Location:  American Horse Lake

Telescope:  Orion 80ED @ f/4.7

Camera:  Hutech Type I, 350D

Exposure Count:  4 @ 2 min, 11 @ 4 min

Guiding:  SBIG ST-402ME, LX200GPS

Acquisition and Focus:  DSLR Focus

Post Processing:

Images Plus - Calibration, Align/Combine, Digital Development

Neat Image - Noise Reduction

Photoshop - Levels Adjustment

Finder Chart

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