Sh2-297 (also known as Sharpless 297) is an emission nebula in the constellation Canis Major. The region was catalogued in 1959 in the extended seconded edition of the Sharpless catalogue.[3] This area is part of the Canis Major OB1 Association, and is a very active area of new star formation.[1]
Studies in 1988 found that the bright star illuminating the nebula was 8th magnitude HD 53623 / HIP 34178 with spectral class B1II/III.[4][1] Later in 2004 it was shown that there was embedded a cold but massive Young Stellar Object or YSO within Sh2-297 near the edge of one of the dark rifts.[5] This object has been observed in the far-infrared, but it is so deeply embedded in an interstellar cloud that it is undetectable in shorter wavelength observations such as the Two Micron All Sky Survey (2MASS), leading it to be originally named "Unidentified young stellar object 1" or UYSO-1.[6] It was further revealed that this unseen stellar source produces a carbon monoxide (CO) bipolar outflow with a total mass of 5.4 M☉ solar masses, while the surrounding extended envelope weighs 30 M☉–40 M☉.[5][1] Some 96 other YSOs have been discovered to be part of Sh-297, having a mean age of one million years and range in masses between 0.3 M☉ and 2.0 M☉.[1] Many variable stars are also assigned with this nebula complex, including the three brightest: MW Ori, TT Ori and V559 Ori.
Distance is estimated between 1.0 and 1.4 kpc. (3,300–4,600 ly.),[1] averaging 1.2 kpc. or 3,900 ly.
History of observationedit
This region was catalogued as part of the major clustering of reflection nebula as CMa R1 by van den Bergh in 1966.[7]Reflection nebulas were identified on blue plates of the Palomar Sky Survey, with positive confirmation made by checking nebulosity on the red plates. It was again later catalogued as LBN 1037 or LBN 225.27-02.42[8]
^ abcdefMallick, K.K.; et al. (2012). "Star Formation Activity in the Galactic H II Region Sh2-297". Astrophysical Journal. 759 (1): 19. arXiv:1209.3420. Bibcode:2012ApJ...759...48M. doi:10.1088/0004-637X/759/1/48. S2CID 59575330.
^Hock, N.; Smith-Moore, M. (1988). Michigan Catalogue of Two-dimensional Spectral Types for the HD Stars. Volume 4, Declinations -26°.0 to -12°.0. Department of Astronomy, University of Michigan, Ann Arbor. Bibcode:1988mcts.book.....H.
also, known, sharpless, emission, nebula, constellation, canis, major, region, catalogued, 1959, extended, seconded, edition, sharpless, catalogue, this, area, part, canis, major, association, very, active, area, star, formation, emission, nebulaobservation, d. Sh2 297 also known as Sharpless 297 is an emission nebula in the constellation Canis Major The region was catalogued in 1959 in the extended seconded edition of the Sharpless catalogue 3 This area is part of the Canis Major OB1 Association and is a very active area of new star formation 1 Sh2 297Emission nebulaObservation data J2000 0 epochRight ascension07h 05m 13 0sDeclination 12 19 00 Distance3 300 4 600 1 lyConstellationCanis MajorDesignationsSh 297 LBN 1039 Ced 90 2 See also Lists of nebulae Studies in 1988 found that the bright star illuminating the nebula was 8th magnitude HD 53623 HIP 34178 with spectral class B1II III 4 1 Later in 2004 it was shown that there was embedded a cold but massive Young Stellar Object or YSO within Sh2 297 near the edge of one of the dark rifts 5 This object has been observed in the far infrared but it is so deeply embedded in an interstellar cloud that it is undetectable in shorter wavelength observations such as the Two Micron All Sky Survey 2MASS leading it to be originally named Unidentified young stellar object 1 or UYSO 1 6 It was further revealed that this unseen stellar source produces a carbon monoxide CO bipolar outflow with a total mass of 5 4 M solar masses while the surrounding extended envelope weighs 30 M 40 M 5 1 Some 96 other YSOs have been discovered to be part of Sh 297 having a mean age of one million years and range in masses between 0 3 M and 2 0 M 1 Many variable stars are also assigned with this nebula complex including the three brightest MW Ori TT Ori and V559 Ori Distance is estimated between 1 0 and 1 4 kpc 3 300 4 600 ly 1 averaging 1 2 kpc or 3 900 ly History of observation editThis region was catalogued as part of the major clustering of reflection nebula as CMa R1 by van den Bergh in 1966 7 Reflection nebulas were identified on blue plates of the Palomar Sky Survey with positive confirmation made by checking nebulosity on the red plates It was again later catalogued as LBN 1037 or LBN 225 27 02 42 8 See also editIC 2177 Southern celestial hemisphereReferences edit a b c d e f Mallick K K et al 2012 Star Formation Activity in the Galactic H II Region Sh2 297 Astrophysical Journal 759 1 19 arXiv 1209 3420 Bibcode 2012ApJ 759 48M doi 10 1088 0004 637X 759 1 48 S2CID 59575330 LBN 1039 SIMBAD Centre de donnees astronomiques de Strasbourg Retrieved March 14 2017 Sharpless S 1959 A Catalogue of H II Regions Astrophysical Journal Supplement 4 257 Bibcode 1959ApJS 4 257S doi 10 1086 190049 Retrieved 9 March 2017 Hock N Smith Moore M 1988 Michigan Catalogue of Two dimensional Spectral Types for the HD Stars Volume 4 Declinations 26 0 to 12 0 Department of Astronomy University of Michigan Ann Arbor Bibcode 1988mcts book H a b Forbrich J Schreyer K Posselt B Klein B Th Henning 2010 An Extremely Young Massive Stellar Object near IRAS 07029 1215 Astrophysical Journal 602 2 843 arXiv astro ph 0311210 Bibcode 2004ApJ 602 843F doi 10 1086 381180 S2CID 8224341 Linz H Krause O Beuther H Henning Th Klein R Nielbock M Stecklum B Steinacker J Stutz A 2010 The structured environments of embedded star forming cores Astronomy and Astrophysics 518 L123 arXiv 1005 1937 Bibcode 2010A amp A 518L 123L doi 10 1051 0004 6361 201014669 ISSN 0004 6361 S2CID 113405209 van den Bergh S 1966 A study of reflection nebulae Astrophysical Journal 71 990 998 Bibcode 1966AJ 71 990V doi 10 1086 109995 LBN 1037 LBN 225 27 02 42 SIMBAD simbad u strasbg fr Retrieved 12 March 2017 Retrieved from https en wikipedia org w index php title Sh2 297 amp oldid 1141182831, wikipedia, wiki, book, books, library,
