WASP-29

WASP-29 is a binary star system 285 light-years (87 parsecs) away in the constellation of Phoenix. The primary star is a K-type main-sequence star. Its comoving companion, a red dwarf star, was discovered in 2021.^[3] The star system kinematically belongs to the thin disk of the Milky Way.^[5] The primary is an old star with small starspot activity and low x-ray flux.^[6]

WASP-29

Observation data Epoch J2000      Equinox J2000
Constellation	Phoenix
Right ascension	23h 51m 31.08391s[1]
Declination	−39° 54′ 24.2582″[1]
Apparent magnitude (V)	11.33[2]
Characteristics
WASP-29A
Evolutionary stage	main sequence star
Spectral type	K4V[3]
B−V color index	0.82
J−H color index	0.478
J−K color index	0.570
WASP-29B
Spectral type	M3V[3]
Astrometry
Radial velocity (Rv)	24.31±0.20[1] km/s
Proper motion (μ)	RA: −56.767(14) mas/yr[1] Dec.: −88.988(13) mas/yr[1]
Parallax (π)	11.4349 ± 0.0151 mas[1]
Distance	285.2 ± 0.4 ly (87.5 ± 0.1 pc)
Position (relative to WASP-29A)[3]
Component	WASP-29B
Epoch of observation	2021
Angular distance	125.2″
Projected separation	10994 AU
Details[4]
WASP-29A
Mass	0.825±0.033 M☉
Radius	0.808±0.044 R☉
Surface gravity (log g)	4.5±0.2 cgs
Temperature	4800±150 K
Metallicity [Fe/H]	0.11±0.14 dex
Rotational velocity (v sin i)	1.50±0.60 km/s
Age	14+0 −7 Gyr
WASP-29B
Mass	0.38[3] M☉
Other designations
CD−40 15273, TOI-192, TIC 183537452, WASP-29, TYC 8015-1020-1, 2MASS J23513108-3954241, DENIS J235131.0-395423[2]
WASP-29A: Gaia DR3 6534414719318886144
WASP-29B: Gaia DR3 6534426740931264896
Database references
SIMBAD	data

Planetary system

The "hot Saturn" class planet WASP-29b was discovered around WASP-29 in 2010.^[5] The planet would have an equilibrium temperature of 960±30 K.^[7] The planetary atmosphere has abundant carbon monoxide but likely lacks methane^[8] and sodium,^[9] although the high and dense cloud deck of WASP-29b prevents high-quality spectroscopic measurements.^[10]

A study in 2018 revealed the stability of planetary orbits in the habitable zone of WASP-29 is significantly affected by the WASP-29b planet.^[11]

The WASP-29 planetary system^[7]

Companion (in order from star)	Mass	Semimajor axis (AU)	Orbital period (days)	Eccentricity	Inclination	Radius
b	0.243+0.020 −0.019 MJ	0.0470±0.0025	3.92271218(25)	<0.059[4]	89.468+0.018 −0.017°	0.775±0.031 RJ

References

1. 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. "WASP-29". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 5 November 2023.
3. Fontanive, Clémence; Daniella Bardalez Gagliuffi (2021), "The Census of Exoplanets in Visual Binaries: population trends from a volume-limited Gaia DR2 and literature search", Frontiers in Astronomy and Space Sciences, 8: 16, arXiv:2101.12667, Bibcode:2021FrASS...8...16F, doi:10.3389/fspas.2021.625250
4. Bonomo, A. S.; Desidera, S.; et al. (June 2017). "The GAPS Programme with HARPS-N at TNG. XIV. Investigating giant planet migration history via improved eccentricity and mass determination for 231 transiting planets". Astronomy & Astrophysics. 602: A107. arXiv:1704.00373. Bibcode:2017A&A...602A.107B. doi:10.1051/0004-6361/201629882. S2CID 118923163.
5. Hellier, Coel; Anderson, D. R.; Collier Cameron, A.; Gillon, M.; Lendl, M.; Maxted, P. F. L.; Queloz, D.; Smalley, B.; Triaud, A. H. M. J.; West, R. G.; Brown, D. J. A.; Enoch, B.; Lister, T. A.; Pepe, F.; Pollacco, D.; Ségransan, D.; Udry, S. (2010). "WASP-29b: A SATURN-SIZED TRANSITING EXOPLANET". The Astrophysical Journal. 723 (1): L60–L63. arXiv:1009.5318. Bibcode:2010ApJ...723L..60H. doi:10.1088/2041-8205/723/1/L60. S2CID 64119308.
6. Dos Santos, L. A.; Bourrier, V.; Ehrenreich, D.; Sanz-Forcada, J.; López-Morales, M.; Sing, D. K.; García Muñoz, A.; Henry, G. W.; Lavvas, P.; Lecavelier Des Etangs, A.; Mikal-Evans, T.; Vidal-Madjar, A.; Wakeford, H. R. (2021), "HST PanCET program: Non-detection of atmospheric escape in the warm Saturn-sized planet WASP-29 B", Astronomy & Astrophysics, 649: A40, arXiv:2103.15688, Bibcode:2021A&A...649A..40D, doi:10.1051/0004-6361/202140491, S2CID 232417342
7. Saha, Suman; Sengupta, Sujan (2021), "Critical Analysis of Tess Transit Photometric Data: Improved Physical Properties for Five Exoplanets", The Astronomical Journal, 162 (5): 221, arXiv:2109.11366, Bibcode:2021AJ....162..221S, doi:10.3847/1538-3881/ac294d, S2CID 237605336
8. Matthew Hardin, Joseph Harrington, K. Stevenson, "WASP-29b: Another Cool Exoplanet With Abundant CO?"
9. A Gemini ground-based transmission spectrum of WASP-29b: a featureless spectrum from 515 to 720 nm
10. Wong, Ian; Chachan, Yayaati; Knutson, Heather A.; Henry, Gregory W.; Adams, Danica; Kataria, Tiffany; Benneke, Björn; Gao, Peter; Deming, Drake; López-Morales, Mercedes; Sing, David K.; Alam, Munazza K.; Ballester, Gilda E.; Barstow, Joanna K.; Buchhave, Lars A.; Dos Santos, Leonardo A.; Fu, Guangwei; Muñoz, Antonio García; MacDonald, Ryan J.; Mikal-Evans, Thomas; Sanz-Forcada, Jorge; Wakeford, Hannah R. (2022), "The Hubble PanCET Program: A Featureless Transmission Spectrum for WASP-29b and Evidence of Enhanced Atmospheric Metallicity on WASP-80b", The Astronomical Journal, 164 (1): 30, arXiv:2205.10765, Bibcode:2022AJ....164...30W, doi:10.3847/1538-3881/ac7234, S2CID 248987053
11. Georgakarakos, Nikolaos; Eggl, Siegfried; Dobbs-Dixon, Ian (April 2018). "Giant Planets: Good Neighbors for Habitable Worlds?". The Astrophysical Journal. 856 (2): 155. arXiv:1804.02183. Bibcode:2018ApJ...856..155G. doi:10.3847/1538-4357/aaaf72.