Galactic Nebula Sharpless 2-207 and 2-208

Sh 2-207 + Sh 2-208
Sh 2-207 + Sh 2-208: Emission nebula Sh 2-207 (left) and Sh 2-208 (right); 500 mm Cassegrain 3625 mm f/7.2; SBIG STL11K; 729+120+120+120 min LRGBB; Bernese Highlands; © 2017 Radek Chromik

History

While searching the photo plates of the «Palomar Observatory Sky Survey» made with the 48 inch Schmidt telescope, the American astronomer Stewart Sharpless came across the two emission nebulae Sh 2-207 and Sh 2-208 and published them in 1959 together with a total of 313 H-II Regions in a catalog. [310]

In 1961 the Soviet astronomer Boris Aleksandrovich Vorontsov-Velyaminov suggested that the faint, round nebula V-V 1-2 (Sh 2-207) could be a typical type IIIb planetary nebula because of the well-defined ring structure. [390] The two Czech astronomers Luboš Perek and Luboš Kohoutek listed the nebula in their «Catalogue of Galactic Planetary Nebulae» published in 1967 under the designation PK 151+2.1. [391] Spectroscopic studies from 1976 showed that Sh 2-207 is more of an H-II region. [392]. In the 2000 reissue it is listed as a misclassified PN and probable H-II region. [146]

Physical Properties

Sharpless 2-207 is a star-forming region, similar to a miniature version of the Rosette Nebula. The age of the star cluster located in the western part of the nebula has been estimated at about 2-3 million years and its kinetic distance at about 4 kpc. [394] The smaller H-II region Sharpless 2-208 is at about the same distance.

Data for für Sh 2-207 and Sh 2-208 [145]
Designations ICRS RA / Dec Typ Diameter
Sh 2-207, LBN 151.25+02.12, PK 151+2.1, V-V 1-2 04h 19m 46.2s / +53° 09' 51" HII (ionized) region 3.3'
Sh 2-208, GSC 03719-00517 04h 19m 32.9s / +52° 58' 41.6" Open (galactic) Cluster 2.37'

Finder Chart

The nebulae Sh 2-207 and Sh 2-208 are located on the border of the constellation Camelopardalis to Perseus. The best viewing time is September to March, when the circumpolar constellation is at its highest.

Chart Galactic Nebula Sharpless 2-207 and 2-208
Galactic Nebula Sharpless 2-207 and 2-208 in constellation Camelopardalis. Chart created using SkySafari 6 Pro and STScI Digitized Sky Survey. [149, 160]

More Objects Nearby (±15°)

References

145SIMBAD astronomical database; simbad.u-strasbg.fr/simbad
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
149SkySafari 6 Pro, Simulation Curriculum; skysafariastronomy.com
160The STScI Digitized Sky Survey; archive.stsci.edu/cgi-bin/dss_form
310«A Catalogue of H II Regions» Stewart Sharpless, US Naval Observatory, 1959; DOI:10.1086/190049; Bibcode:1959ApJS....4..257S
390«New Planetary and Peculiar Gaseous Nebulae» Vorontsov-Vel'Yaminov, B. A.; Soviet Astronomy, Vol. 5, p.278, October 1961; Bibcode:1961SvA.....5..278V
391«Morphological study of planetary nebulae. I. Observed forms of planetary nebulae.» Kromov, G. S.; Kohoutek, L.; Bulletin of the Astronomical Institutes of Czechoslovakia, Vol. 19, p. 1-11 (1968); Bibcode:1968BAICz..19....1K
392«Interaction of hot stars and of the interstellar medium. VIII. Low-dispersion spectra of galactic nebulae and planetary nebulae.» Chopinet, M. ; Lortet-Zuckermann, M. C.; Astronomy and Astrophysics, Suppl. Ser., Vol. 25, p. 179-191 (1976); Bibcode:1976A&AS...25..179C
394«LOW-METALLICITY YOUNG CLUSTERS IN THE OUTER GALAXY. I. Sh 2-207» Chikako Yasui, Naoto Kobayashi, Alan T. Tokunaga, Masao Saito, and Natsuko Izumi; Published 2016 February 9; The Astronomical Journal, Volume 151, Number 3; DOI:10.3847/0004-6256/151/3/50