Captured from a rooftop in Nyon, Switzerland, this 25-hour deep integration reveals the Rosette Nebula (NGC 2237–9), a vast star-forming region about 5,200 light-years away in the constellation Monoceros. At its heart lies the young open cluster NGC 2244, whose hot, massive stars carve a hollowed cavity in the surrounding gas. The blue tones trace oxygen-rich regions, while the warm reds highlight hydrogen emission, outlining the nebula’s iconic rose-like structure. Faint sulfur extensions stretch outward, exposing shock fronts and tenuous filaments that mark the ongoing interaction between stellar radiation and the parent molecular cloud.

Aesthetically, the image balances a luminous central bubble with delicate, wind-swept tendrils that fade into the surrounding darkness, giving a strong sense of depth and scale. The added SII data enriches the outer shells and subtle streamers, emphasizing the nebula’s dynamic edges and revealing fragile structures often lost in shorter exposures. Against a finely resolved star field, the Rosette appears both serene and powerful, a cosmic bloom shaped by light, gravity, and time.

Spanning hundreds of light-years across the Monoceros constellation, this stunning 4-panel mosaic captures the vast and intricate connection between two iconic nebulae—the Cone Nebula (NGC 2264) and the Rosette Nebula (NGC 2237)—revealing their structure in exquisite Sulfur-II (SII), Hydrogen-alpha (Hα), and Oxygen-III (OIII) narrowband detail.

On the left, the towering Cone Nebula, shaped by intense stellar winds and radiation, stands like a shadowy pillar of interstellar dust and ionized gas. This dark structure, nearly 7 light-years tall, is being slowly eroded by the ultraviolet light of nearby young, hot stars in the Christmas Tree Cluster, carving out glowing ridges and intricate filaments of gas.

Stretching toward the right, the Rosette Nebula dominates the scene with its vast, circular structure—an enormous star-forming complex located about 5,000 light-years away. At its heart lies the open cluster NGC 2244, whose blazing young stars flood the nebula with ultraviolet radiation, ionizing the surrounding gas and sculpting a luminous cavity filled with intricate tendrils of material. The nebula’s layered appearance reveals shock fronts, dark dust lanes, and vast plumes of ionized gas driven outward by stellar feedback.

This SHO palette brings out the nebulae’s complex composition: sulfur (SII) in deep red-orange hues, hydrogen-alpha (Hα) in golden-yellow tones, and oxygen (OIII) in striking blue-greens, highlighting the energetic processes shaping these celestial structures. The seamless blending of this 4-panel mosaic unveils a breathtaking connection between these regions, illustrating the turbulent yet beautiful cycle of star formation and destruction that defines the Milky Way’s vast stellar nurseries.

​Imaging telescopes or lenses:​ Takahashi FSQ130ED
Imaging cameras: FLI ML16200 ADT
Mounts: Takahashi EM 400 Temma 2M
​Guiding telescopes or lenses: Takahashi FS60CB
Guiding cameras: QHY CCD QHY 5 II
Focal Extender / Reducer: None
Software: Sequence Generator Pro SGP (for capture) PHD 2 (guiding), Astro Pixel Processor & PixInsight,
Filters: Astrodon Ha, OIII, SII.

Accessories: Robofocus Focuser, ATIK EFW3

Original Resolution: 3570 x 4225
Dates: 1st Jan to 4th Jan 2020

Frames:
Astrodon Ha 30 x 10'
Astrodon OIII 30 x 10'
Astrodon SII 36 x 10'

Total integration = 16 hours.

Copyright: Brendan Kinch