From Wikipedia, the free encyclopedia
(Redirected from HAT-P-36b)
HAT-P-36 / Tuiren
Diagram showing star positions and boundaries of the Canes Venatici constellation and its surroundings
Location of HAT-P-36 (circled) within Canes Venatici
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Canes Venatici[1]
Right ascension 12h 33m 03.9061s[2]
Declination +44° 54′ 55.196″[2]
Apparent magnitude (V) 12.26
Spectral type G
Radial velocity (Rv)−16.434 km/s
Proper motion (μ) RA: −11.622(8) mas/yr[2]
Dec.: 8.138(10) mas/yr[2]
Parallax (π)3.4055 ± 0.0110 mas[2]
Distance958 ± 3 ly
(293.6 ± 0.9 pc)
Mass1.022 ± 0.049 M
Radius1.096 ± 0.056 R
Temperature5580 ± 100.0 K
Metallicity [Fe/H]0.26 ± 0.08 dex
Age6.6 ± 1.8 Gyr
Other designations
Tuiren, Gaia DR3 1541532207133249920, TYC 3020-2221-1, 2MASS J12330390+4454552[3]
Database references

HAT-P-36, also referred to as Tuiren[4] is a 12th magnitude G-type main-sequence star estimated to be approximately 958 light-years away from Earth[2] in the constellation Canes Venatici. HAT-P-36 is too faint to be seen with the naked eye, but it is possible to view it with binoculars or a small telescope. In 2012 a hot Jupiter-type exoplanet was discovered orbiting HAT-P-36 with an orbital period of about 1.3 Earth days.[5] In December 2019, HAT-P-36 was named Tuiren and its planetary companion, HAT-P-36b, was named Bran as a result of Ireland's contribution to the 2019 NameExoWorlds campaign.[6] Bran has a mass approximately 1.8 times that of Jupiter and a radius 1.2 times larger.


Tuiren (centre) as viewed in the Sloan Digital Sky Survey. The bright star to the top-left is TYC 3020-2195-1, an A-type main-sequence star approximately 3,156 light-years away.[7]

HAT-P-36 and its planet are named after characters from The Birth of Bran, a story in the book Irish Fairy Tales by James Stephens. The book is a re-telling of various stories from Irish folklore. Tuiren was the aunt of the mythical hero Fionn mac Cumhaill and was turned into a hound by the fairy Uchtdealbh after Tuiren married her husband. Bran and Sceólan were the two puppies mothered by Tuiren while she was a dog. They were cousins of Fionn mac Cumhaill. The names were proposed by John Murphy, a teacher at Regina Mundi College, Cork.[8]


The HAT-P-36b planetary system[9]
(in order from star)
Mass Semimajor axis
Orbital period
Eccentricity Inclination Radius
b (Bran) ≥1.832±0.099 MJ 0.0238±0.0004 1.327347±0.000003 0.063±0.032 86±1.3° 1.264±0.071 RJ

HAT-P-36b (Bran) was discovered in 2012 by the HATNet Project using the transit method.[5] A search for transit timing variation did not result in detection of additional planets in the system as at 2021.[10] Surprisingly, a planetary orbital period increase by 0.014 seconds per year was detected by 2021.[11]

Size comparison
Jupiter HAT-P-36b (Bran)
Jupiter Exoplanet


  1. ^ Roman, Nancy G. (1987). "Identification of a Constellation From a Position". Publications of the Astronomical Society of the Pacific. 99 (617): 695–699. Bibcode:1987PASP...99..695R. doi:10.1086/132034. Vizier query form
  2. ^ a b c d e 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. ^ "HAT-P-36". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2023-02-23.
  4. ^ "IAU100 NameExoWorlds Approved Names" (PDF). NameExoWorlds. International Astronomical Union. Retrieved 24 July 2020.
  5. ^ a b "HAT-P-36". Open Exoplanet Catalogue. Retrieved 24 July 2020.
  6. ^ Smith, Niall (29 September 2019). "Sky Matters: Ireland has the chance to name a star and a planet - any ideas?". Irish Examiner. Retrieved 24 July 2020.
  7. ^ "TYC 3020-2195-1". Centre de Données astronomiques de Strasbourg. SIMBAD. Retrieved 24 July 2020.
  8. ^ Gorey, Colm (18 December 2019). "Cork teacher names exoplanet and star after Irish mythical dogs". Silicon Republic. Retrieved 24 July 2020.
  9. ^ "Planet HAT-P-36 b". Extrasolar Planets Encyclopaedia. Retrieved 24 July 2020.
  10. ^ Sonbas, E.; Karaman, N.; Özdönmez, A.; Er, H.; Dhuga, K. S.; Göğüş, E.; Nasiroglu, I.; Zejmo, M. (2022), "Probing Transit Timing Variations of three hot Jupiters: HATP-36b, HATP-56b, and WASP-52b", Monthly Notices of the Royal Astronomical Society, 509 (4): 5102–5116, arXiv:2111.05220, doi:10.1093/mnras/stab3270
  11. ^ Yalçınkaya, S.; Baştürk, Ö.; ElHelweh, F.; Esmer, E.M.; Yörükoğlu, O.; Yılmaz, M.; Şenavcı, H.V.; Kılıçoğlu, T.; Selam, S.O. (2021), "Analysis of the Most Precise Light Curves of HAT-P-36 Detrended from Spot Signals", Acta Astronomica, 71 (3), arXiv:2111.11531, doi:10.32023/0001-5237/71.3.3, S2CID 244488216