Southworth, JohnJohnSouthworthMancini, L.L.ManciniDominik, M.M.DominikJorgensen, U. G.U. G.JorgensenBozza, VVBozzaBurgdorf, M. J.M. J.BurgdorfJaimes, R. FigueraR. FigueraJaimesHaikala, L. K.L. K.HaikalaHenning, ThThHenningHinse, T. C.T. C.HinseHundertmark, M.M.HundertmarkLonga-Pena, P.P.Longa-PenaRabus, M.M.RabusRahvar, S.S.RahvarSajadian, S.S.SajadianSkottfelt, J.J.SkottfeltSnodgrass, C.C.Snodgrass2026-10-092026-10-092022Southworth, John; Mancini, L.; Dominik, M.; Jorgensen, U. G.; Bozza, V; Burgdorf, M. J.; Jaimes, R. Figuera; Haikala, L. K.; Henning, Th; Hinse, T. C.; Hundertmark, M.; Longa-Pena, P.; Rabus, M.; Rahvar, S.; Sajadian, S.; Skottfelt, J.; Snodgrass, C. (2022). VLT, GROND, AND DANISH TELESCOPE OBSERVATIONS OF TRANSITS IN THE TRAPPIST-I SYSTEM. OBSERVATORY, 142(1290), 220-229. https://doi.org/10.48550/arxiv.2207.058740029-7704https://hdl.handle.net/20.500.12740/25086TRAPPIST-I is an ultra-cool dwarf that hosts seven known transiting planets. We present photometry of the system obtained using three telescopes at ESO La Silla (the Danish 1.54-m telescope and the 2.2-m MPI telescope) and Paranal (Unit Telescope I of the Very Large Telescope). We obtained I8 light-curves from the Danish telescope, eight from the 2.2-m and four from the VLT. From these we measure 25 times of mid-transit for four of the planets (b, c, f, g). These light-curves and times of mid-transit will be useful in determining the masses and radii of the planets, which show variations in their transit times due to gravitational interactions.http://purl.org/coar/access_right/c_abf2Stellar, planetary, and galactic studiesAstronomy and Astrophysical ResearchHistory and Developments in AstronomyArticulohttps://doi.org/10.48550/arxiv.2207.05874