R Trianguli (abbreviated as R Tri) is a short-period oxygen-rich[4]Mira variable in Triangulum with a period of 266.9 days,[2] discovered by T. H. E. C. Espin in 1890.[7] It is losing about 1.1×10−7M☉/yr, close to average for a short-period Mira variable.[8] While most short-period Mira variables reside in the Galactic halo, R Trianguli is a member of the thick disk, and its proper motion is fairly high for its distance.[4] Its angular diameter in the K band was measured in 2002 to be, on average, 5.22±0.30 mas, with a shape suggesting that there is an optically thin disk structure surrounding the star.[4]
^ a b c d e fVallenari, 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.
^ a b c d"General Catalog of Variable Stars table at VizieR". vizier.cds.unistra.fr.
^ a b c d eThompson, R. R.; Creech-Eakman, M. J.; Akeson, R. L. (May 2002). "Time-dependent Asymmetries in the Atmosphere of the Mira Variable R Trianguli through Infrared Interferometry". The Astrophysical Journal. 570 (1): 373–378. doi:10.1086/339736. S2CID 121032726.
^McDonald, I.; Zijlstra, A. A.; Boyer, M. L. (2012). "Fundamental Parameters and Infrared Excesses of Hipparcos Stars". Monthly Notices of the Royal Astronomical Society. 427 (1): 343–57. arXiv:1208.2037. Bibcode:2012MNRAS.427..343M. doi:10.1111/j.1365-2966.2012.21873.x. S2CID 118665352.
^Gore, John Ellard (1903). The Stellar Heavens: An Introduction to the Study of the Stars and Nebulæ. Chatto & Windus. p. 52.
^Jura, M. (February 1994). "The origin and evolution of short-period Miras in the solar neighborhood: Constraints on the life cycle of old stars". The Astrophysical Journal. 422: 102. Bibcode:1994ApJ...422..102J. doi:10.1086/173707.
^"Download Data". aavso.org. AAVSO. Retrieved 1 October 2021.