Two days later on 20th March 2026 (one day after new moon) were were continued to be blessed with clear skies and I was able to observe the large Rosette Nebula in Monoceros. This lies a little below (i.e. south) of the Cone Nebula and Christmas Tree Cluster I had observed a few days before. This is what I obtained after 272x15s (68 minutes) on the Dwarf 3:-
The first frame was taken at 20:58 UT and the last at 22:56 UT (midpoint 21:42 UT). Here the gain was 60 and duo-band filter employed in the Dwarf 3. Processed in Stellar Studio (auto settings). The image has been binned x2 and the gain and saturation have been increased in Photoshop.
In the centre of the nebula is a young cluster of stars (NGC 2244, also called Caldwell 50) and these bright stars are illuminating the surrounding nebula (NGC 2239, Caldwell 49). UV light from these stars is ionising hydrogen gas in the nebula and causing the atoms to emit a prominent red line (H alpha) on recombination. Also seen in this image are denser areas of dust and gas silhouetted against the brighter nebula. These are called Bok Globules and these can be sites where new stars are in the process of being formed.
All text and images © Duncan Hale-Sutton 2026
No comments:
Post a Comment