WASP-159

WASP-159

Observation data Epoch J2000.0       Equinox J2000.0
Constellation	Caelum [1]
Right ascension	04h 32m 32.75581s [2]
Declination	−38° 58′ 05.9529″ [2]
Apparent magnitude  (V)	12.84±0.24 [3]
Characteristics
Evolutionary stage	subgiant [2]
Spectral type	F9 [4]
B−V color index	−0.21 [3]
Astrometry
Radial velocity (Rv)	35.16±0.01 [4] km/s
Proper motion (μ)	RA: −0.586 mas/yr [2] Dec.: +5.347 mas/yr [2]
Parallax (π)	1.3723±0.0098  mas [2]
Distance	2,380 ± 20  ly (729 ± 5  pc)
Details [4]
Mass	1.41±0.12  M☉
Radius	2.11±0.10  R☉
Luminosity	4.674+0.064 −0.053 [2]   L☉
Surface gravity (log g)	3.94±0.04  cgs
Temperature	6,120±140  K
Metallicity [Fe/H]	+0.22±0.12  dex
Rotational velocity (v sin i)	5.7±0.4 km/s
Age	3.40±0.95  Gyr
Other designations
TOI-1903, TIC 77156657, WASP-159, TYC 7579-251-1 [5]
Database references
SIMBAD	data
Exoplanet Archive	data

WASP-159 is a star located in the southern constellation Caelum, the chisel. It has an apparent magnitude of 12.84, ^[3] making it readily visible in telescopes with an aperture of at least four inches, but not to the naked eye. The star is located relatively far at a distance of 2,380 light-years based on recent parallax measurements from the Gaia spacecraft, ^[2] but it is receding with a heliocentric radial velocity of 35.2  km/s . ^[4]

WASP-159 has a stellar classification of F9 indicating that it is a late F-type star. ^[4] It appears to be ceasing hydrogen fusion at its core and evolving towards the red giant branch. ^[4] It has 1.41 times the Sun's mass and 2.11 times the radius of the Sun. ^[4] It radiates 4.674 times the luminosity of the Sun ^[2] from its photosphere at an effective temperature of 6,120  K , ^[4] giving it a whitish-yellow hue when viewed in a telescope. WASP-159 is metal enriched with an iron abundance 166% that of the Sun, and it is estimated to be 3.4 billion years old. ^[4]

Planetary system

In 2019, SuperWASP discovered a transiting exoplanet orbiting the star after spectral and radial velocity observations. WASP-159b is a "bloated" hot Jupiter that takes roughly 3.8 days to revolve around its host star in a circular orbit. ^[4]

The WASP-159 planetary system ^[4]

Companion (in order from star)	Mass	Semimajor axis (AU)	Orbital period (days)	Eccentricity	Inclination	Radius
b	0.55±0.08  MJ	0.0538±0.0015	3.8404008+0.0000063 −0.0000064	0.00 (fixed)	88.1±1.4 °	1.38±0.09  RJ

References

1. Roman, Nancy G. (1987). "Identification of a constellation from a position". Publications of the Astronomical Society of the Pacific . 99 (617): 695. Bibcode:1987PASP...99..695R. doi: 10.1086/132034 . Constellation record for this object at VizieR.
2. 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.
3. Høg, E.; Fabricius, C.; Makarov, V. V.; Urban, S.; Corbin, T.; Wycoff, G.; Bastian, U.; Schwekendiek, P.; Wicenec, A. (1 March 2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics. 355: L27 –L30. Bibcode:2000A&A...355L..27H. ISSN   0004-6361.
4. Hellier, Coel; Anderson, D. R.; Bouchy, F.; Burdanov, A.; Collier Cameron, A.; Delrez, L.; Gillon, M.; Jehin, E.; Lendl, M.; Nielsen, L. D.; Maxted, P. F. L.; Pepe, F.; Pollacco, D.; Queloz, D.; Ségransan, D.; Smalley, B.; Triaud, A. H. M. J.; Udry, S.; West, R. G. (1 January 2019). "New transiting hot Jupiters discovered by WASP-South, Euler/CORALIE, and TRAPPIST-South". Monthly Notices of the Royal Astronomical Society. 482 (1): 1379–1391. arXiv: 1803.02224 . Bibcode:2019MNRAS.482.1379H. doi: 10.1093/mnras/sty2741 . ISSN   0035-8711.
5. "WASP-159". SIMBAD . Centre de données astronomiques de Strasbourg.