AAPOD2 Image Archives
Rho Ophiuchi molecular clouds complex mosaic
Image Description and Details : The main goal of this project was to capture the exceptional, extremely colorful, gigantic region enclosing the emission, reflection and dark nebulae around stars named Rho Ophiuchi, Antares and Alniyat, as well as neighboring objects (M4 globular cluster and others). This region is commonly referred as Rho Ophiuchi Molecular Clouds Complex in the astronomical literature. The nebulae have very intensive colors depending on the ionized and molecular gas composition (yellow-orange and reddish colors) or due to the visible light reflexion (blue colored nebulae). Dark nebulae does not transmit much light due to the presence of interstellar dust. This region covers a gigantic region on the night sky compared to many other deep space objects and is located on the border of the Scorpius and Ophiuchus constellations. A total length of 8 Full Moons could be placed side-by-side on the wider, horizontal side of this mosaic. The high dynamic range of colors and contrast in each panel, as well as the size of each file (few gigabytes due to the high resolution) resulted in complex and unusually long computer processing procedures. This 4-panel mosaic is produced by combining the integrated data collected using two different telescopes (Askar FRA400 and William Optics FLT-91) in the last two years. The same astronomic camera (ZWO ASI294 MM Pro with thermoelectric cooling) and same dichroic broad-range filters (Chroma RGB set) were used. Total integration time is on average 4.5 hours per panel. Imaging sessions required a total of 7 car trips to two different locations (Rudine near Skopje and Radibush near Kriva Palanka) spanning driving around 800 km. Difference in the telescopes focal length (280 and 432 mm) and changes in the atmospheric conditions between different nights impose real processing challenge. Technical details Telescope: William Optics Fluorostar 91 and Fla t6AIII focal reducer/flattener (fl=432 mm). Imaging camera: ZWO ASI294MM Pro. Guiding camera: ZWO ASI174MM Mini via ZWO OAG;. Guiding and acquisition control: AsiAir Plus. Mount: iOptron CEM40EC. Filters: Chroma (RGB). Frames: Red: 124x180" (6h 12') (gain: 120.00) -15°C bin 1x1; Green: 128x180" (6h 24') (gain: 120.00) -15°C bin 1x1; Blue: 121x180" (6h 3') (gain: 120.00) -15°C bin 1x1. Total integration of the mosaic: 18h 39m. Integration per panel: 4h 40m. Dates: June 4, 2021 · June 8, 2021 · July 6, 2021 · May 24, 2022 · June 2, 2022 · June 27, 2022 · July 4, 2022.
Copyright: Sasho Panov