| HDW2 One can note the unusual striations and a dark spot toward the south. The brighter part is surrounded by darker ring and finally an outer brighter ring. Beyond this "bright" area, there is a faint and diffuse ring halo captured in the Halpha emission line. Some OIII signal is also noticeable beyond the main structure. Note also the open cluster Trumpler 3 (Lund 101, Cr 36, Harvard 1), just north to the PN. |
HDW2( = SH2-200 / PNG 138.1+04.1 A noter la structure striée particulière et un anneau brillant séparé de la partie centrale par un fin espace plus sombre. Une zone plus sombre se trouve aussi près du centre, couronné par un un chapelet d'étoiles, lui conférant là aussi un caractère original. A noter également l'amas ouvert Trumpler 3 (Lund 101, Cr 36, Harvard 1), juste au nord de la NP. |
 Composite "HOO+RGB" color image RGB: 10x5' for each color channel OIII: 24x15'=6h Ha: 17x15'=4h15 Takahashi FSQ106ED refractor CCD camera Atik 4000 (Kodak KAI-4021M) @-20°C Astrodon R, G, B, Ha (5nm) and OIII (5nm) filters |
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Relative response for the Ha and OIII emission lines.
 Streched version  Annotation  Wide mosaic field toward HFG1 and Abell 6 (North to the left) |
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 DSS red/blue composite image |
Other images: http://www.astrodonimaging.com/gallery/display.cfm?imgID=250 Publications: http://dx.doi.org/10.1051/0004-6361/200913984 http://adsabs.harvard.edu/abs/1987A&AS...69..519H |
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