HAT-P-23

HAT-P-23 is a G-type main-sequence star about 1280 light-years away. It has a rapid rotation (rotation period equal to 7 days) for its advanced age of 4 billion years, and exhibits a strong starspot activity.[3] The star may be in the process of being spun up by the giant planet on close orbit.[4]The star is enriched in heavy elements, having about 140% amount of metals compared to solar abundance.

HAT-P-23
Observation data
Epoch J2000      Equinox J2000
Constellation Delphinus
Right ascension  20h 24m 29.7235s[1]
Declination +16° 45′ 43.8103″[1]
Apparent magnitude (V) 11.94[1]
Characteristics
Spectral type G0V
Astrometry
Radial velocity (Rv)-14.324 km/s
Proper motion (μ) RA: 13.263 mas/yr
Dec.: -5.412 mas/yr
Parallax (π)2.7129 ± 0.0351[1] mas
Distance1,200 ± 20 ly
(369 ± 5 pc)
Details[2]
Mass1.13±0.035 M☉
Radius1.203±0.074 R☉
Luminosity1.58±0.23 L☉
Surface gravity (log g)4.33±0.05 cgs
Temperature5905±80 K
Metallicity0.15±0.04
Rotational velocity (v sin i)8.1±0.5 km/s
Age4.0±1.0 Gyr
Other designations
Moriah, Gaia DR2 1808938730710633984, TYC 1632-1396-1, GSC 01632-01396, 2MASS J20242972+1645437[1]
Database references
SIMBADdata

Naming

In 2019, the HAT-P-23 star havs received a proper name Moriah and planet HAT-P-23b - Jebus at an international NameExoWorlds contest.[5]. These names mean the ancient name of the mount at the center of Jerusalem city, and ancient (pre-Roman) name of Jerusalem itself, respectively.

Planetary system

In 2010 a transiting hot Jupiter like planet was detected.[2] It has an measured nightside temperature of 2154±90 K.[6] The planet is on unstable orbit, and expected to be engulfed by parent star after 7.5+2.9
−1.8 million years from now,[7] although measurements of orbital decay has yielded an inconclusive results as in 2020.[8] The planetary orbit is probably aligned with the equatorial plane of the star, misalignment equal to 15±22°.[9] The color of planetary atmosphere is grey.[10]

Size comparison of HAT-P-23 b and Jupiter
The HAT-P-23 planetary system[2][7][6][10]
Companion
(in order from star)		 Mass Semimajor axis
(AU)		 Orbital period
(days)		 Eccentricity Inclination Radius
b (Jebus) 2.09±0.111 MJ 0.0232±0.0002 1.2128868±0.0000004 0.096 85.1±1.5° 1.224±0.037 RJ

References
  1. HAT-P-23 -- Star
  2. HAT-P-20b–HAT-P-23b: FOUR MASSIVE TRANSITING EXTRASOLAR PLANETS, 2010, arXiv:1008.3388
  3. Testing the solar activity paradigm in the context of exoplanet transits, 2020, arXiv:2001.01093
  4. Planet-star interactions with precise transit timing. I. The refined orbital decay rate for WASP-12 b and initial constraints for HAT-P-23 b, KELT-1 b, KELT-16 b, WASP-33 b, and WASP-103 b, 2018, arXiv:1812.02438
  5. IAU 100 NameExoWorlds Approved Names
  6. WARM SPITZER AND PALOMAR NEAR-IR SECONDARY ECLIPSE PHOTOMETRY OF TWO HOT JUPITERS: WASP-48b AND HAT-P-23b
  7. PARAMETERS OF RECENT TRANSITS OF HAT-P-23b, 2012, arXiv:1211.6481
  8. The continuing search for evidence of tidal orbital decay of hot Jupiters, 2020, arXiv:2002.02606
  9. Spin-orbit inclinations of the exoplanetary systems HAT-P-8, HAT-P-9 HAT-P-16, and HAT-P-23, 2011, arXiv:1105.3849
  10. Physical properties of the HAT-P-23 and WASP-48 planetary systems from multi-colour photometry, 2015, arXiv:1503.00762

This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.