NGC 2359 (CMa)

NGC 2359 (CMa)

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Date/Site: March 9., 2009, AAR-observatory in Presberg
Exposure/
Filter:
L: 3 x 10 minutes,
B: 3 x 5 minutes, G: 3 x 5 minutes, R: 2 x 5 minutes, (-25°C)
Camera: SBIG ST10XME with CFW9 and SBIG LRGB-filters
Optics/
Instrument:
26cm-Newton on Gemini 41 Observatory
Focusing with Robofocus
Darks, flats, deblooming, alignment and stacking: MaximDL 5,
Levels and curves: Photoshop CS3.

A Wolf-Rayet-star produces a bubble of hot gas behind a dense molecular cloud. NGC 2359 was adopted as „my“ object during my years in Munich. With a 12“-Dobson and O3 or UHC-filters ander a dark sky a lot of detail is visible. The bubble is plainly visible and even appears mottled. The edge of the gas and dust cloud in front of the emerging shell sharply turns upwards on both sides. For us it always looked more like a snail with its house rather than a northern warrior's helmet.
In the beginning conditions were quite good with a strong easterly wind, limiting magnitude 5.8 to 6.0m, -7°C. From 23:30 from the south a cloud bank moved in, which should not have reached us at all. At 1:00 conditions forced me to quit.
The winter's milky way already was in the southwest when I started my sequence of exposures. The last red-frame was lost, as the object already sank very deep and the camera lost the guiding star. Because of the low declination seeing deteriorated significantly and the stars appear comparatively bloated. Autoguiding was quite busy compared to the nights before.

© Friedhelm Hübner, last revision:  03.12.2023