210113 - IC2177 "Sea Gull" nebula
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click image to enlarge
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ASTRO:
type=Emission Nebula, const=Monoceros, mag=15.2, dist=3700 ly, size=100 ly IMAGE: location=EB Driveway, BrtlCls=4; moon=1% WxCr; exposure=DSLR OSC: 39x300s (3.3h), ISO1600 EQUIPMENT: camera=Nikon D90 (mod); optics=ES102 w0.8x rdcr. eff. F=571mm, f/5.6; filter=STC Astro Duo-NB clip-in; mount=Celestron AVX; guiding=Orion 60x240mm, ZWO ASi224MC SOFTWARE: acquisition=Stellarium, APT, PHD2, processing=DSS, PhotoshopCC, RCAstro_GradXT & NoiseXT OTHER: false L added to simulate LRGB; Blue channel curve-stretched to bring color forward |
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IC 2177 is a region of nebulosity that lies along the border between the constellations Monoceros and Canis Major. It is a roughly circular H-II region centered on the star HD 53367 (visible in the "eye" region of the seagull). This nebula was discovered in 1885 by Welsh amateur astronomer Isaac Roberts and was described by him as "pretty bright, extremely large, irregularly round, very diffuse." The name Seagull Nebula is sometimes applied by amateur astronomers, although it more properly includes the neighboring regions of star clusters, dust clouds and reflection nebulae. This larger region includes the open clusters NGC 2335 (visible in this image at the top of the left "wing") and NGC 2343 (just to the left of the "tail").
The nebula lies appx 3700 light years from us here on Earth. At that distance, its "wingspan" is calculated to be appx 240 light-years across.
Astronomers list the stars clustered near what appears as the seagull's eye as NGC 2327. The cluster was born about 1.5 million years ago. The single star in the eye is the brightest and hottest of the newborn stars in the entire nebula; it heats up the dust so that it glows in infrared light.
In the image above, you may notice a small, prominent bluish arc over a star toward the lower right corner. This is a bow shock from runaway star FN Canis Majoris, which is a binary star system in the southern Canis Major constellation, near its northern border with Monoceros. The binary is dimly visible as a single star to the naked eye with a combined apparent visual magnitude of 5.41. The system is located at a distance of approximately 3,000 light years from our Sun; and based on parallax viewing from here on Earth, it is drifting away from us with a radial velocity of appx 31 km/s. It is a runaway star (not part of a cluster), being associated only with the Seagull nebula. The primary star of the pair is a massive star with estimates ranging from 19 to 36 times the mass of our Sun, and with luminosity estimates of 122,000 to 690,000 times that of our Sun. The magnitude 7.04 companion star is located at an angular separation of 0.60″ from the primary. It may be barely seen by first enlarging, and then zooming-in on the image.
The prominent and conspicuous bow-shock feature of this star is caused by the powerful stellar winds of the binary pair encountering the nebula cloud as they traverse through space. It is a very desirable detail for amateur astronomers to capture in their images of the Sea Gull nebula.
The nebula lies appx 3700 light years from us here on Earth. At that distance, its "wingspan" is calculated to be appx 240 light-years across.
Astronomers list the stars clustered near what appears as the seagull's eye as NGC 2327. The cluster was born about 1.5 million years ago. The single star in the eye is the brightest and hottest of the newborn stars in the entire nebula; it heats up the dust so that it glows in infrared light.
In the image above, you may notice a small, prominent bluish arc over a star toward the lower right corner. This is a bow shock from runaway star FN Canis Majoris, which is a binary star system in the southern Canis Major constellation, near its northern border with Monoceros. The binary is dimly visible as a single star to the naked eye with a combined apparent visual magnitude of 5.41. The system is located at a distance of approximately 3,000 light years from our Sun; and based on parallax viewing from here on Earth, it is drifting away from us with a radial velocity of appx 31 km/s. It is a runaway star (not part of a cluster), being associated only with the Seagull nebula. The primary star of the pair is a massive star with estimates ranging from 19 to 36 times the mass of our Sun, and with luminosity estimates of 122,000 to 690,000 times that of our Sun. The magnitude 7.04 companion star is located at an angular separation of 0.60″ from the primary. It may be barely seen by first enlarging, and then zooming-in on the image.
The prominent and conspicuous bow-shock feature of this star is caused by the powerful stellar winds of the binary pair encountering the nebula cloud as they traverse through space. It is a very desirable detail for amateur astronomers to capture in their images of the Sea Gull nebula.