Like all the stars of this kind, TU And is a coolasymptotic giant branch star, meaning it is fusing hydrogen and helium in concentric shells outside an inert core of carbon and oxygen formed earlier in its life on thehorizontal branch. Its period is stable at 316.8 days.[3]
The modelled properties of TU Andromedae at maximum brightness are not in agreement with available models of Mira stars (which work forMira itself). It is uncertain if the problem is in the measured parameters of the star or in imperfections of the models. It had a mass between 1.15 and 1.4 M☉ when it was on themain sequence but is now less massive.[6]
^abcdTU And, database entry, Combined General Catalog of Variable Stars (GCVS4.2, 2004 Ed.), N. N. Samus, O. V. Durlevich, et al.,CDS IDII/250 Accessed on line 2009-06-30.
^Høg, E.; Fabricius, C.; Makarov, V. V.; Urban, S.; Corbin, T.; Wycoff, G.; Bastian, U.; Schwekendiek, P.; Wicenec, A. (2000), "The Tycho-2 catalogue of the 2.5 million brightest stars",Astronomy & Astrophysics,355:L27 –L30,Bibcode:2000A&A...355L..27H.
^abcdAnders, F.; Khalatyan, A.; Chiappini, C.; Queiroz, A. B.; Santiago, B. X.;Jordi, C.; Girardi, L.; Brown, A. G. A.; Matijevič, G.; Monari, G.; Cantat-Gaudin, T.; Weiler, M.; Khan, S.; Miglio, A.; Carrillo, I.; Romero-Gómez, M.; Minchev, I.; De Jong, R. S.; Antoja, T.; Ramos, P.; Steinmetz, M.; Enke, H. (2019), "Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia DR2 stars brighter than G = 18",Astronomy and Astrophysics,628: A94,arXiv:1904.11302,Bibcode:2019A&A...628A..94A,doi:10.1051/0004-6361/201935765,S2CID131780028.
^abHillen, M.; Verhoelst, T.; Degroote, P.; Acke, B.; van Winckel, H. (2012), "The dynamic atmospheres of Mira stars: comparing the CODEX models to PTI time series of TU Andromedae",Astronomy & Astrophysics,538: L6,arXiv:1201.5815,Bibcode:2012A&A...538L...6H,doi:10.1051/0004-6361/201118653.
