Sh2-101 in Vulpecula




© Velimir Popov & Emil Ivanov 2015
Size: 1600 px
Sh2-101 (also known as Tulip Nebula) is an emission nebula in the constellation Swan. It is located in the central-southern part of the constellation, in the center of a stretch of the Milky Way that is very bright and full of stars. It is located about 45 'north-east of the star η Cygni and extends for about twenty in the NE-SW direction. It has an elongated and irregular shape; the best time for its observation in the evening sky falls between the months of June and November. It is a large H II region located on the initial stretch of the Orion's Arm, about 2700 parsecs (8750 light years) away from the Solar System, beyond the large nebulous complex of Cygnus X, from which it would be no more than 500 parsecs away.. This distance coincides with that estimated for the OB Cygnus OB3 association, which contains about thirty massive stars of the first spectral classes with an age of about 8.3 million years. The source of the gas ionizing radiation from the nebula is believed to be the star HD 227018, a blue giant of class O6.5III and an apparent magnitude of 9.01. According to the Avedisova, the nebula would host some active star formation phenomena, as evidenced by the presence of four sources of infrared radiation listed in the IRAS catalog: IRAS 19581 + 3504, IRAS 19579 + 3509, IRAS 19584 + 3506 and IRAS 19584+ 3515, as well as some radio wave sources

Image details:


Center of field RA 20:00:04 (h:m:s)
Center of field DE +35:20:01 (deg:m:s)
Size 56.1 x 43.3 (arcmin)
Pixel scale: 2.84 (arcsec/pixel)
Orientation: Up is 90.6 degrees E of N
Charts and image details obtained from
Optic(s): ASA 12" Astrograph @ f/3.6 (Newton)
Mount: ASA DDM85 Standard
Camera: SBIG STL 11000 M
Filters: Luminance, Red, Green, Blue, Astronomik filters
Dates/Times: 6.08.2012
Location: IRIDA Observatory, BG, longitude: E 24 44' 18", latitude: N 41 41' 42"
Exp. Details: L:6x10 min; R:6x10 min, G:6x10 min, B:6x10 min; Ha:6x15 . Bin 2 Total exp.time: 330min
More details: Dark and flat frames reduction
Processing: PixInsight / PS
Copyright: Velimir Popov and Emil Ivanov 2015. All Rights Reserved
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