Galactic Nebula NGC 1985

NGC 1985
NGC 1985: Galactic nebula in Auriga; 500 mm Cassegrain f=3625mm / f7.2; SBIG STL11K; 45+3*30 min LRGB; Bernese Highlands; © 2011 Radek Chromik

History

The NGC 1985 nebula was discovered on November 13, 1790 by the German-British astronomer Wilhelm Herschel. [196] John L. E. Dreyer described it in his 1888 «New General Catalogue of Nebulae and Clusters of Stars» as follows: «considerably faint, small, round, rather suddenly brighter center.» [313] In the «Catalogue of Galactic Planetary Nebulae» published in 1967, the two Czech astronomers Luboš Perek and Luboš Kohoutek still considered NGC 1985 to be a planetary nebula and gave it the designation PK 176+0.1. This error has been corrected in the 2001 new edition. [146]

Physical Properties

NGC 1985
NGC 1985: Sections from different Surveys: PanSTARRS/DR1 (visual: z 867.9 nm, g 486.6 nm), 2MASS (infrared: J 1.23 μm, H 1.66 μm, K 2.16 μm), AllWISE (infrared: W4 22 μm, W2 4.6 μm, W3 3.4μm) [147]

Also known as AFGL 5157 (Air Force Geophysical Laboratory) or Mol 11, the object hosts a molecular cloud-riddled, active star-forming region with H2O masers, H2 nodes, massive protostar candidates, and an H-II region. The area is approximately 13.5 pc in diameter at a distance of approximately 1.8 kpc. Embedded star cluster IRAS 05345+3157 is mainly visible in infrared light. An expanding shell of hydrogen, also glowing in the infrared, surrounds the cluster, which is estimated to be around 10 million years old. Research suggests that an early collision of two molecular cloud filaments may have triggered star formation. [367] [367]

«Revised New General Catalogue and Index Catalogue» Dr. Wolfgang Steinicke, 2021 [277]
DesignationNGC 1985
TypeRN
Right Ascension05h 37m 47.8s
Declination+31° 59' 20"
Diameter0.68 arcmin
Photographic (blue) magnitude12.7 mag
Dreyer DescriptioncF, S, R, psbM
IdentificationPK 176+0.1, CS=13.6, not a PN

Finder Chart

Der galaktische Nebel NGC 1985 befindet sich im Sternbild Auriga (Fuhrmann), welches von September bis April am besten sichtbar ist.

Chart NGC 1985
Chart created using SkySafari 6 Pro and STScI Digitized Sky Survey. [149, 160]

References

146«Version 2000 of the Catalogue of Galactic Planetary Nebulae» L. Kohoutek, A&A Volume 378, Number 3, November II 2001; DOI:10.1051/0004-6361:20011162
147Aladin Lite; aladin.u-strasbg.fr/AladinLite (2020-12-23)
149SkySafari 6 Pro, Simulation Curriculum; skysafariastronomy.com
160The STScI Digitized Sky Survey; archive.stsci.edu/cgi-bin/dss_form
196Celestial Atlas by Curtney Seligman; cseligman.com/text/atlas.htm (2020-12-28)
277«Historische Deep-Sky Kataloge» von Dr. Wolfgang Steinicke; klima-luft.de/steinicke (2021-02-17)
313«A New General Catalogue of Nebulae and Clusters of Stars, being the Catalogue of the late Sir John F.W. Herschel, Bart., revised, corrected, and enlarged» Dreyer, J. L. E. (1888); Memoirs of the Royal Astronomical Society. 49: 1–237; Bibcode:1888MmRAS..49....1D
367«The Cluster-forming Site AFGL 5157: Colliding Filamentary Clouds and Star Formation» L. K. Dewangan; Published 2019 October 14; The Astrophysical Journal, Volume 884, Number 1; DOI:10.3847/1538-4357/ab4189