Astronomy:NGC 6210

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Short description: Planetary nebula in the constellation Hercules
NGC 6210
Emission nebula
Planetary nebula
File:NGC 6210 HST.tif
A Hubble Space Telescope (HST) image of NGC 6210
Credit: HST/NASA/ESA
Observation data: J2000 epoch
Right ascension 16h 44m 29.51960s[1]
Declination+23° 47′ 59.4913″[1]
Distance5.4 ± 1.3 kly (1.7 ± 0.4 kpc)[2] ly
Apparent dimensions (V)40″ × 30″[2]
ConstellationHercules
Physical characteristics
Radius0.5 ly
DesignationsPN G043.1+37.7, BD+24° 3048, HD 151121, IRAS 16423+2353, NGC 6210[3]
See also: Lists of nebulae

NGC 6210 is a planetary nebula located in the constellation Hercules, approximately 5.4 ± 1.3 kly from the Sun.[2] It is positioned about 38° above the galactic plane at a vertical distance of about 3.3 kilolight-years (1 kpc) and thus has little extinction from intervening interstellar dust.[4] This object was first recorded as a star-like feature by Joseph Lalande on March 22, 1799. However, credit for the discovery of a nebula goes to Wilhelm Struve in 1825. John L. E. Dreyer described it as, "a planetary nebula, very bright, very small, round, disc and border".[5]

This nebula is "very amorphous and irregular" in shape, but forms a rough ellipsoid.[4] It consists of two parts; a bright inner region filled with arches and filaments spanning 13″ × 16", and a larger and fainter outer volume that has a pair of "tubular" structures. The inner region has an expansion velocity ranging over 19–24 km/s.[2] The emission from the outer part of the nebula is only about 1% of the total.[4]

The central star has an apparent visual magnitude of 12.66 and the spectrum matches a hydrogen-rich star of type O(H). It has an estimated temperature of 65,000 K. The abundances of the nebula suggest a low initial mass for the central star, probably ~0.9 M.[4] Outflow from this star has been measured with velocities of 2,180 km/s, and the estimated mass loss rate is 2.2×10−9 M yr−1. There appears to be a collaminated jet feature to the northwest, suggesting the central star is ejecting material along two and possibly four such directions.[6]

Gallery

References

  1. 1.0 1.1 Brown, A. G. A. (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics 616: A1. doi:10.1051/0004-6361/201833051. Bibcode2018A&A...616A...1G.  Gaia DR2 record for this source at VizieR.
  2. 2.0 2.1 2.2 2.3 Bohigas, J. et al. (February 2015). "Echelle spectroscopy and photoionization modelling of the entire planetary nebula NGC 6210". Monthly Notices of the Royal Astronomical Society 447 (1): 817–835. doi:10.1093/mnras/stu2389. Bibcode2015MNRAS.447..817B. 
  3. "NGC 6210". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=NGC+6210. 
  4. 4.0 4.1 4.2 4.3 Pottasch, S. R. et al. (May 2009). "Abundances in the planetary nebula NGC 6210". Astronomy and Astrophysics 499 (1): 249–256. doi:10.1051/0004-6361/200911654. Bibcode2009A&A...499..249P. 
  5. Seligman, Courtney. "New General Catalogue objects: NGC 6200 - 6249". https://cseligman.com/text/atlas/ngc59a.htm#5986. 
  6. Phillips, J. P.; Cuesta, L. (March 1996). "NGC 6210: an Observational Case Study of a Jet Emitting Source". Astronomical Journal 111: 1227. doi:10.1086/117868. Bibcode1996AJ....111.1227P. 

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