HD 210277 is a single[9] star in the equatorial constellation of Aquarius. It has an apparent visual magnitude of 6.54,[2] which makes it a challenge to view with the naked eye, but it is easily visible in binoculars. The star is located at a distance of 69.6 light years from the Sun based on parallax, but is drifting closer with a radial velocity of −20.9 km/s.[5]

HD 210277
Observation data
Epoch J2000      Equinox J2000
Constellation Aquarius
Right ascension 22h 09m 29.8658s[1]
Declination −07° 32′ 55.162″[1]
Apparent magnitude (V) 6.54[2]
Characteristics
Spectral type G8V[3] or G8/K0V[4]
U−B color index 0.43
B−V color index 0.773
Astrometry
Radial velocity (Rv)−20.855±0.0003[5] km/s
Proper motion (μ) RA: 85.407(29) mas/yr[1]
Dec.: −450.617(23) mas/yr[1]
Parallax (π)46.8515 ± 0.0283 mas[1]
Distance69.61 ± 0.04 ly
(21.34 ± 0.01 pc)
Absolute magnitude (MV)4.90±0.05[6]
Details[7]
Mass1.007+0.040
−0.039
 M
Radius1.087+0.015
−0.016
 R
Luminosity1.002[8] L
Surface gravity (log g)4.369±0.020 cgs
Temperature5,705±35 K
Metallicity [Fe/H]0.170±0.097 dex
Rotation40.8 d[9]
Rotational velocity (v sin i)1.888±0.158 km/s
Age6.471+1.744
−1.643
[7]
8.929±2.671[2] Gyr
Other designations
BD−08°5818, GJ 9769, HD 210277, HIP 109378, SAO 145906, PPM 206033, LTT 8887, NLTT 53073, GCRV 13920, 2MASS J22092985-0732548[10]
Database references
SIMBADdata
ARICNSdata

An early classification of this star was a G0 dwarf,[11] and some sources still use this value.[12] More modern classification surveys list it as G8V,[3] matching a late G-type main-sequence star.[9] It is older than the Sun with a very low level of chromospheric activity[3] and is spinning with a projected rotational velocity of 1.9 km/s. The star has a slightly higher mass and larger radius than the Sun.[7]

Planetary system

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In 1999 it was announced that a dust disk orbiting HD 210277, similar to that produced by the Kuiper Belt, had been imaged, lying between 30 and 62 AU from the star.[13] However, observations with the Spitzer Space Telescope failed to detect any infrared excess at 70 micrometres or at 24 micrometres wavelengths.[14][15] Subsequent measurements by the Herschel Space Observatory did detect an excess at 100 and 160 micrometres. A model fit to the emission matches a disk orbiting at 160 AU with a mean temperature of 22 K.[16] The disk signal is fairly strong, with S/N equal to 6.6.[8]

The only known exoplanet was discovered using 34 radial velocity measurements taken from 1996 to 1998 at W. M. Keck Observatory. It has a minimum mass greater than Jupiter orbiting the star in 442 days.[9] The high eccentricity (ovalness) of the exoplanet's orbit means it is unlikely that there is a companion planet co-orbiting the star at a trojan point.[12]

The HD 210277 planetary system[17]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b >1.29 ± 0.11 MJ 1.138 ± 0.066 442.19 ± 0.50 0.476 ± 0.017
debris disk 160[16] AU

See also

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References

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  1. ^ a b c d Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
  2. ^ a b c Delgado Mena, E.; et al. (April 2019). "Abundance to age ratios in the HARPS-GTO sample with Gaia DR2. Chemical clocks for a range of [Fe/H]". Astronomy & Astrophysics. 624: 24. arXiv:1902.02127. Bibcode:2019A&A...624A..78D. doi:10.1051/0004-6361/201834783. S2CID 90259810. A78.
  3. ^ a b c Gray, R. O.; et al. (October 2003). "Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 Parsecs: The Northern Sample. I.". The Astronomical Journal. 126 (4): 2048–2059. arXiv:astro-ph/0308182. Bibcode:2003AJ....126.2048G. doi:10.1086/378365. S2CID 119417105.
  4. ^ Houk, N.; Swift, C. (1999). "Michigan catalogue of two-dimensional spectral types for the HD Stars". Michigan Spectral Survey. 5. Bibcode:1999MSS...C05....0H.
  5. ^ a b Soubiran, C.; et al. (2018). "Gaia Data Release 2. The catalogue of radial velocity standard stars". Astronomy and Astrophysics. 616: A7. arXiv:1804.09370. Bibcode:2018A&A...616A...7S. doi:10.1051/0004-6361/201832795. S2CID 52952408.
  6. ^ Gonzalez, Guillermo; et al. (1999). "Parent Stars of Extrasolar Planets. IV. 14 Herculis, HD 187123, and HD 210277". The Astrophysical Journal Letters. 511 (2): L111–L114. Bibcode:1999ApJ...511L.111G. doi:10.1086/311847.
  7. ^ a b c Soto, M. G.; Jenkins, J. S. (2018). "Spectroscopic Parameters and atmosphEric ChemIstriEs of Stars (SPECIES). I. Code description and dwarf stars catalogue". Astronomy and Astrophysics. 615: A76. arXiv:1801.09698. Bibcode:2018A&A...615A..76S. doi:10.1051/0004-6361/201731533. S2CID 119107228.
  8. ^ a b Krivov, A. V.; Eiroa, C.; Löhne, T.; Marshall, J. P.; Montesinos, B.; Del Burgo, C.; Absil, O.; Ardila, D.; Augereau, J.-C.; Bayo, A.; Bryden, G.; Danchi, W.; Ertel, S.; Lebreton, J.; Liseau, R.; Mora, A.; Mustill, A. J.; Mutschke, H.; Neuhäuser, R.; Pilbratt, G. L.; Roberge, A.; Schmidt, T. O. B.; Stapelfeldt, K. R.; Thébault, Ph.; Vitense, Ch.; White, G. J.; Wolf, S. (2013), "HERSCHEL's "COLD DEBRIS DISKS": BACKGROUND GALAXIES OR QUIESCENT RIMS OF PLANETARY SYSTEMS?", The Astrophysical Journal, 772 (1): 32, arXiv:1306.2855, Bibcode:2013ApJ...772...32K, doi:10.1088/0004-637X/772/1/32, S2CID 11877636
  9. ^ a b c d Marcy, Geoffrey W.; et al. (1999). "Two New Planets in Eccentric Orbits". The Astrophysical Journal. 520 (1): 239–247. arXiv:astro-ph/9904275. Bibcode:1999ApJ...520..239M. doi:10.1086/307451. S2CID 16827678.
  10. ^ "HD 210277". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2020-12-29.
  11. ^ Cannon, A. J.; Pickering, E. C. (October 1993). "Henry Draper Catalogue and Extension". VizieR On-Line Data Catalog: III/135A. Bibcode:1993yCat.3135....0C. Originally published in: Harv. Ann. 91-100 (1918-1924)
  12. ^ a b Funk, B.; Schwarz, R.; Süli, Á.; Érdi, B. (July 2012). "On the stability of possible Trojan planets in the habitable zone: an application to the systems HD 147513 and HD 210277". Monthly Notices of the Royal Astronomical Society. 423 (4): 3074–3082. Bibcode:2012MNRAS.423.3074F. doi:10.1111/j.1365-2966.2012.21121.x.
  13. ^ Trilling, D. E.; et al. (2000). "Circumstellar Dust Disks around Stars with Known Planetary Companions". The Astrophysical Journal. 529 (1): 499–505. Bibcode:2000ApJ...529..499T. doi:10.1086/308280. S2CID 121999545.
  14. ^ Beichman, C. A.; et al. (2005). "Planets and Infrared Excesses: Preliminary Results from a Spitzer MIPS Survey of Solar-Type Stars". The Astrophysical Journal. 622 (2): 1160–1170. arXiv:astro-ph/0412265. Bibcode:2005ApJ...622.1160B. doi:10.1086/428115. S2CID 6633656.
  15. ^ Bryden, G.; et al. (2009). "Planets and Debris Disks: Results from a Spitzer/MIPS Search for Infrared Excess" (PDF). The Astrophysical Journal. 705 (2): 1226–1236. Bibcode:2009ApJ...705.1226B. doi:10.1088/0004-637X/705/2/1226.
  16. ^ a b Eiroa, C.; et al. (December 2011). "Herschel discovery of a new class of cold, faint debris discs". Astronomy & Astrophysics. 536: L4. arXiv:1110.4826. Bibcode:2011A&A...536L...4E. doi:10.1051/0004-6361/201117797. S2CID 14234038.
  17. ^ Butler, R. P.; et al. (2006). "Catalog of Nearby Exoplanets". The Astrophysical Journal. 646 (1): 505–522. arXiv:astro-ph/0607493. Bibcode:2006ApJ...646..505B. doi:10.1086/504701. S2CID 119067572.
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