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.
Etymology
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]
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]
^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
^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): 223, arXiv:2111.11531, Bibcode:2021AcA....71..223Y, doi:10.32023/0001-5237/71.3.3, S2CID244488216