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The nebula NGC 1999, together with Herbig-Haro objects in Orion.

NGC 1999 is a reflection nebula illuminated by the variable star V380.  Strikingly, there is a dark T-shaped globule visible in the nebula.  Bok globules are small (in an astronomical sense, just 103 to 105 AU radius!) clouds of gas and dust which are typically condensing to form a star or stars.

Just below NGC 1999 are the Herbig-Haro objects H-H 1 and H-H 2.  Although catalogued separately they are part of the same structure, being opposite ends of a bipolar jet of plasma.  H-H objects are shock excited nebulae - the result of jets moving away from young stars at high speeds.  Other H-H objects are also present in the region imaged, but are too faint to show here.


Image info

Telescope:  Celestron 9.25" Schimdt-Cassegrain at f/6.3

Focus:  Prime focus

Filter:  Celestron LPR

Mount:  Vixen GPD with Skysensor2000

Camera:  Modified Canon EOS 300D, at ISO400

Guiding:  700mm refractor guidescope, SAC7 camera, autoguided with Guidedog software

Exposure:  Total 52 mins (13 x 240s)

Date:  16th January 2005

Processing:  RAW file conversion, Offset and Dark subtraction, flat fielding, registering and stacking done in IRIS.  Curve stretching and colour saturation enhancement by Luminance Layering in Photoshop CS.


Not as many frames as I would have liked, but nevertheless quite a deep image, with a mag 20.0 star (ref. USNO B) visible.


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