A possible misaligned orbit for the young planet AU Mic c
Year: 2024
Type: article
Abstract: ABSTRACT The AU Microscopii planetary system is only 24 Myr old, and its geometry may provide clues about the early dynamical history of planetary systems. Here, we present the first measurement of the Rossiter–McLaughlin effect for the warm sub-Neptune AU Mic c, using two transits observed simultaneously with the European Southern Observatory's (ESO's) Very Large Telescope (VLT)/Echelle SPectrograph for Rocky Exoplanets and Stable Spectroscopic Observations (ESPRESSO), CHaracterising ExOPlanet Satellite (CHEOPS), and Next-Generation Transit Survey (NGTS). After correcting for flares and for the magnetic activity of the host star, and accounting for transit-timing variations, we find the sky-projected spin–orbit angle of planet c to be in the range $\lambda _{\mathrm{c}}=67.8_{-49.0}^{+31.7}$ degrees (1$\sigma$). We examine the possibility that planet c is misaligned with respect to the orbit of the inner planet b ($\lambda _{\mathrm{b}}=-2.96_{-10.30}^{+10.44}$), and the equatorial plane of the host star, and discuss scenarios that could explain both this and the planet’s high density, including secular interactions with other bodies in the system or a giant impact. We note that a significantly misaligned orbit for planet c is in some degree of tension with the dynamical stability of the system, and with the fact that we see both planets in transit, though these arguments alone do not preclude such an orbit. Further observations would be highly desirable to constrain the spin–orbit angle of planet c more precisely.
Authors: H Yu, Z Garai, M Cretignier, Gy M Szabó, S Aigrain, D Gandolfi, E M Bryant, A C M Correia, B Klein, A Brandeker, J E Owen, M N Günther, J N Winn, A Heitzmann, H M Cegla, T G Wilson, S Gill, L Kriskovics, O Barragán, A Boldog, L D Nielsen, N Billot, M Lafarga, A Meech, Y Alibert, R Alonso, T Bárczy, D Barrado, S C C Barros, W Baumjohann, D Bayliss, W Benz, M Bergomi, L Borsato, C Broeg, A Collier Cameron, Sz Csizmadia, P E Cubillos, M B Davies, M Deleuil, A Deline, O D S Demangeon, B -O Demory, A Derekas, L Doyle, B Edwards, J A Egger, D Ehrenreich, A Erikson, A Fortier, L Fossati, M Fridlund, K Gazeas, M Gillon, M Güdel, Ch Helling, K G Isaak, L L Kiss, J Korth, K W F Lam, J Laskar, A Lecavelier des Etangs, M Lendl, D Magrin, P F L Maxted, J McCormac, B Merín, C Mordasini, V Nascimbeni, S M O’Brien, G Olofsson, R Ottensamer, I Pagano, E Pallé, G Peter, D Piazza, G Piotto, D Pollacco, D Queloz, R Ragazzoni, N Rando, H Rauer, I Ribas, N C Santos, G Scandariato, D Ségransan, A E Simon, A M S Smith, S G Sousa, R Southworth, M Stalport, M Steinberger, S Sulis, S Udry, B Ulmer, S Ulmer-Moll, V Van Grootel, J Venturini, E Villaver, N A Walton, P J Wheatley
Institutions: University of Oxford, Eötvös Loránd University, Slovak Academy of Sciences, Astronomical Institute of the Slovak Academy of Sciences, University of Turin, University College London, Centro de Física da Universidade de Coimbra, University of Coimbra, Stockholm University, AlbaNova, University of California, Los Angeles, Imperial College London, European Space Agency, European Space Research and Technology Centre, Princeton University, University of Geneva, University of Warwick, Konkoly Observatory, HUN-REN Research Centre for Astronomy and Earth Sciences, Ludwig-Maximilians-Universität München, European Southern Observatory, University of Bern, Center for Space and Habitability, Universidad de La Laguna, Instituto de Astrofísica de Canarias, Centro de Astrobiología, Universidade do Porto, Institute of Astrophysics and Space Sciences, Centro de Astrofísica da Universidade do Porto, Austrian Academy of Sciences, Space Research Institute, Osservatorio Astronomico di Padova, University of St Andrews, Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR), Osservatorio Astrofisico di Torino, National Institute for Astrophysics, Lund University, Centre National de la Recherche Scientifique, Aix-Marseille Université, Laboratoire d’Astrophysique de Marseille, Space Research Organisation Netherlands, Leiden University, Leiden Observatory, Chalmers University of Technology, National and Kapodistrian University of Athens, University of Liège, University of Vienna, Graz University of Technology, Université Paris Sciences et Lettres, Observatoire de Paris, Institut de Mécanique Céleste et de Calcul des Éphémérides, Institut d'Astrophysique de Paris, Université Pierre-et-Marie-Curie, Keele University, European Space Astronomy Centre, Queen's University Belfast, Osservatorio Astrofisico di Catania, University of Padua, University of Cambridge, ETH Zurich, Freie Universität Berlin, Institute of Space Sciences, Institut d'Estudis Espacials de Catalunya, European Space Operations Centre
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $3,012
Funders: Centre national d'études spatiales, National Science Foundation, Simons Foundation, Spine Education and Research Institute, Fondazione CRT, Slovenská Akadémia Vied, UK Space Agency, UK Research and Innovation, Ministerio de Ciencia, Innovación y Universidades, Centres de Recerca de Catalunya, European Space Agency, Royal Society, University of Warwick, European Commission, Deutsche Forschungsgemeinschaft, Agence Nationale de la Recherche, Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung, Swedish National Space Agency, Austrian Science Fund, Fonds De La Recherche Scientifique - FNRS, Generalitat de Catalunya, Centre National d’Etudes Spatiales, Federación Española de Enfermedades Raras, Ministerio de Ciencia e Innovación, Agentúra na Podporu Výskumu a Vývoja, Nemzeti Kutatási Fejlesztési és Innovációs Hivatal, Instituto de Astrofísica de Canarias, Horizon 2020 Framework Programme, Science and Technology Facilities Council, Fundação para a Ciência e a Tecnologia, Staatssekretariat für Bildung, Forschung und Innovation, European Regional Development Fund, Agencia Estatal de Investigación, Nuclear Fuel Cycle and Supply Chain, H2020 European Research Council
Awards: G1011896320, G1089506725, G1129048233, The Next Generation Transit Survey (NGTS): Operations 2019-2022, G121809054, G1276317268, G13101216, G1329126115, G1353885700, Astronomy at St Andrews 2021 - 2024, G1483381719, TITANIA: TIme variabiliTy As a New window on exoplanet clImAtes, G1594096898, G1622782223, G1690109813, G1767413778, Spectroscopy of hot twilights in exoplanetary atmospheres, G1839585985, G185997775, Od interagujúcich hviezd k exoplanétam, G1916647502, G19485122, G1952066623, G195395952, G1998765129, G2001806450, G2013905886, G2031648612, Chasing Earth-like exoplanets around close Sun-like stars, G210990444, NCCR PlanetS: Origin, evolution and characterisation of planets, G2178350086, G2188020438, G229093490, G2309174360, G2313451655, G2328137084, G2346020423, G2499501003, MSSL Astrophysics Consolidated Grant 2022-25, G2628364946, G2660406951, G302750986, G3052186010, Centro de Física da Universidade de Coimbra, G3161872288, G3170351587, Instituto de Astrofísica e Ciências do Espaço, G3210141531, Virtual Laboratories for Exoplanets and Planet Forming Disks, G3293336813, Overcoming stellar activity in radial velocity planet searches, G3345895242, Instituto de Astrofísica e Ciências do Espaço, G3388932788, G3413881215, G3439265645, G3453679952, G3480869486, G3487392653, G3487714248, G3567832761, G3570713056, G3660363561, G3690828678, G3715634343, G3783317134, G3838811725, G3891694003, The Next Generation Transit Survey (NGTS): Deployment and Operations, G4069126126, G4099950093, G4167963696, G4192228184, G428931209, G430104392, G434337789, G4386951474, G4484233699, G4563145523, G4623258783, G4655338613, Planet Evaporation as a Window into Exoplanetary Origins, G480727374, G491858407, G4937468798, G4967432405, G5017669361, G5043543010, G5080475149, Sem título, Sem título, G5175525644, G526596183, Formation and Evolution of planetary systems, G533670914, G5389530922, G5392910068, G5404395142, G5555131222, G5631677044, G5696905997, G57763700, G5783525505, G5805922419, G5845768719, G5968966496, G617610489, G6180974586, G6242881339, G6255773888, G6281504974, G6327042824, G6502414728, G6513613686, G6620961257, G662651173, G676769616, G683931746, G6859194979, G6956462562, G6997658380, G7082474794, G7084143925, G7197638789, Centro de Física da Universidade de Coimbra, G7240651115, G7321246223, G7371495850, G7394145161, G7425137858, G7536812067, G7573124349, G7578079922, G7628805400, G7745503578, G7751555771, G7762426073, G7805626310, G7822658684, Astrophysics at Keele: planets, stars and galaxies, G7941669009, G7984235579, Planet Formation in Binaries: linking theory and observations, G8081747916, G8132079559, Alexander von Humboldt and the Globalization of Science: Networks of Knowledge between Germany and the United States in the 19th Century, G8308124115, G8500932100, G8505061131, G8508424114, G8510727784, G8512683158, G8684520763, G8884446413, G897484643, G937346533, G993971353
OpenAlex ID: W4404797548