CHEOPS photometry from 2024 reveals a reversal in the transit-timing variations of AU Mic c

Garai, Z.; Szabó, Gy. M.; Gandolfi, D.; Brandeker, A.; Bonfanti, A.; Billot, N.; Benz, W.; Heitzmann, A.; Olofsson, G.; Kriskovics, L.; Boldog, Á.; Borsato, L.; Bekkelien, A.; Bruno, G.; Osborn, H. P.; Ulmer-Moll, S.; Wilson, T. G.; Alibert, Y.; Alonso, R.; Bárczy, T.; Barrado, D.; Barros, S. C. C.; Baumjohann, W.; Broeg, C.; Castro-González, A.; Collier Cameron, A.; Correia, A. C. M.; Csizmadia, Sz.; Cubillos, P. E.; Davies, M. B.; Deleuil, M.; Deline, A.; Demangeon, O. D. S.; Demory, B.-O.; Derekas, A.; Edwards, B.; Ehrenreich, D.; Erikson, A.; Fortier, A.; Fossati, L.; Fridlund, M.; Gazeas, K.; Gillon, M.; Güdel, M.; Günther, M. N.; Helling, Ch.; Isaak, K. G.; Keller, T.; Kiss, L. L.; Kitzmann, D.; Korth, J.; Lam, K. W. F.; Laskar, J.; Lecavelier des Etangs, A.; Leleu, A.; Lendl, M.; Magrin, D.; Maxted, P. F. L.; Merín, B.; Mordasini, C.; Nascimbeni, V.; Orikhovskyi, D.; Ottensamer, R.; Pagano, I.; Pallé, E.; Peter, G.; Piazza, D.; Piotto, G.; Pollacco, D.; Pribulla, T.; Queloz, D.; Ragazzoni, R.; Rando, N.; Rauer, H.; Ribas, I.; Rieder, M.; Santos, N. C.; Scandariato, G.; Ségransan, D.; Simon, A. E.; Smith, A. M. S.; Sousa, S. G.; Southworth, R.; Stalport, M.; Steinberger, M.; Sulis, S.; Udry, S.; Ulmer, B.; Van Grootel, V.; Venturini, J.; Villaver, E.; Viotto, V.; Walton, N. A.
Referencia bibliográfica

Astronomy and Astrophysics

Fecha de publicación:
9
2026
Número de autores
93
Número de autores del IAC
3
Número de citas
0
Número de citas referidas
0
Descripción
We present new CHEOPS transit observations of AU Mic b and AU Mic c obtained between June and September 2024, extending the baseline of transit-timing measurements of this young planetary system. For AU Mic b, the timing signal is well established, with a semi-amplitude (10 ± 3 min) and a characteristic modulation timescale (1168 ± 20 d) consistent with previous determinations. By contrast, the new CHEOPS data show that the large transit-timing deviation of AU Mic c reported previously was not sustained. After the steadily increasing timing trend observed in 2022 and 2023, the 2024 timings returned closer to the zero point of the observed-minus-calculated diagram, indicating a reversal of the previously reported behavior. For AU Mic c, both the transit-timing semi-amplitude (46 ± 26 min) and the characteristic modulation timescale (2150 ± 110 d) remain tentative. These results highlight the importance of continued long-term monitoring of the AU Mic system.