Jump to content

HD 215497

Coordinates:Sky map22h46m36.7543s,−56° 35′ 58.322″
From Wikipedia, the free encyclopedia
HD 215497
Observation data
EpochJ2000.0EquinoxJ2000.0
Constellation Tucana
Right ascension 22h46m36.75396s[1]
Declination −56° 35′ 58.3285″[1]
Apparent magnitude(V) 8.96[2]
Characteristics
Spectral type K3V[2]
Apparent magnitude(B) 9.913[3]
Apparent magnitude(J) 7.339±0.024[3]
Apparent magnitude(H) 6.917±0.053[3]
Apparent magnitude(K) 6.784±0.024[3]
B−Vcolor index 0.953±0.025[3]
Astrometry
Radial velocity(Rv)+49.31[3]km/s
Proper motion(μ)RA:−54.660±0.041[1]mas/yr
Dec.:−61.028±0.045[1]mas/yr
Parallax(π)24.6339 ± 0.0324mas[1]
Distance132.4 ± 0.2ly
(40.59 ± 0.05pc)
Absolute magnitude(MV)5.77[3]
Details[4]
Mass0.86±0.02M
Radius0.87±0.02R
Luminosity0.47±0.02L
Surface gravity(logg)4.49±0.03cgs
Temperature5,128±12K
Metallicity[Fe/H]0.23±0.07[2]dex
Rotational velocity(vsini)1.67[2]km/s
Age9.9±2.8Gyr
Other designations
CPD−57°10139,HD215497,HIP112441,SAO247578,PPM350516,TYC8826-00247-1,2MASSJ22463675-5635584[5]
Database references
SIMBADdata
Exoplanet Archivedata

HD 215497is a single[4]starin the southernconstellationofTucana.It has an orange hue with anapparent visual magnitudeof 8.96,[2]which is too dim to be viewed with the naked eye. A 2015 survey ruled out the existence of any stellar companions at projected distances from 26 to 300astronomical units.[6]Based onparallaxmeasurements,[1]it is located at a distance of 132light yearsfrom theSun.The star is drifting further away with aradial velocityof +49 km/s, having come as close as 45 light-years some 774,000 years ago.[3]Theabsolute magnitudeof this star is 5.77.[3]

Thestellar classificationof HD 215497 is K3V,[2]indicating this is aK-type main-sequence starthat is generating energy throughcorehydrogen fusion.The star is about ten[4]billion years old with a lowmagnetic activitylevel and is spinning with aprojected rotational velocityof 1.67 km/s.[2]It is smaller than the Sun, with 86% of theSun's massand 87% of theradius.[4]This is ametal-richstar, which means the abundance of heavier elements in theatmosphereis significantly higher than in the Sun.[2]It is radiating 47% of theluminosity of the Sunfrom itsphotosphereat aneffective temperatureof 5,128 K.[4]

Planetary system

[edit]

Announced in 2009, twoextrasolar planetswere discovered to be orbiting the star.[2]Both planets are less massive thanJupiter.The inner exoplanetHD 215497 borbits very close to the star and is termed a "hot super-Earth".Theouter exoplanetHD 215497 cis agiant planetthat orbits a little bit further from the star than theEarth,at around1.282AU,with a high eccentricity. A check fortransitsof the inner planet did not reveal any passages.[7]

The HD 215497 planetary system[2]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b ≥6.6M🜨 0.047 3.93404 ± 0.00066 0.16 ± 0.09
c ≥0.33MJ 1.282 567.94 ± 2.70 0.49 ± 0.04

References

[edit]
  1. ^abcdefBrown, A. G. A.;et al. (Gaia collaboration) (August 2018)."GaiaData Release 2: Summary of the contents and survey properties ".Astronomy & Astrophysics.616.A1.arXiv:1804.09365.Bibcode:2018A&A...616A...1G.doi:10.1051/0004-6361/201833051.Gaia DR2 record for this sourceatVizieR.
  2. ^abcdefghijLo Curto, G.; et al. (2015)."The HARPS search for southern extra-solar planets. XXII. Multiple planet systems from the HARPS volume limited sample".Astronomy and Astrophysics.512.A48.arXiv:1411.7048.Bibcode:2010A&A...512A..48L.doi:10.1051/0004-6361/200913523.
  3. ^abcdefghiAnderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation".Astronomy Letters.38(5): 331.arXiv:1108.4971.Bibcode:2012AstL...38..331A.doi:10.1134/S1063773712050015.S2CID119257644.
  4. ^abcdeBonfanti, A.; et al. (2016). "Age consistency between exoplanet hosts and field stars".Astronomy & Astrophysics.585:14.arXiv:1511.01744.Bibcode:2016A&A...585A...5B.doi:10.1051/0004-6361/201527297.S2CID53971692.A5.
  5. ^"HD 215497".SIMBAD.Centre de données astronomiques de Strasbourg.Retrieved2019-11-08.
  6. ^Mugrauer, M.; Ginski, C. (12 May 2015)."High-contrast imaging search for stellar and substellar companions of exoplanet host stars".Monthly Notices of the Royal Astronomical Society.450(3): 3127–3136.Bibcode:2015MNRAS.450.3127M.doi:10.1093/mnras/stv771.hdl:1887/49340.Retrieved19 June2020.
  7. ^Gillon, M.; et al. (May 2017). "The Spitzer search for the transits of HARPS low-mass planets. II. Null results for 19 planets".Astronomy & Astrophysics.601:23.arXiv:1701.01303.Bibcode:2017A&A...601A.117G.doi:10.1051/0004-6361/201629270.S2CID86862862.A117.