Astrophysics - Earth and Planetary Astrophysics; Astrophysics - Solar; and Stellar Astrophysics
Abstract :
[en] Carbon is an essential element for life but how much can be delivered to young planets is still an open question. The chemical characterization of planet-forming disks is a crucial step in our understanding of the diversity and habitability of exoplanets. Very low-mass stars (less than 0.2 M<SUB>⊙</SUB>) are interesting targets because they host a rich population of terrestrial planets. Here we present the James Webb Space Telescope detection of abundant hydrocarbons in the disk of a very low-mass star obtained as part of the Mid-InfraRed Instrument mid-INfrared Disk Survey (MINDS). In addition to very strong and broad emission from C<SUB>2</SUB>H<SUB>2</SUB> and its <SUP>13</SUP>C<SUP>12</SUP>CH<SUB>2</SUB> isotopologue, C<SUB>4</SUB>H<SUB>2</SUB>, benzene and possibly CH<SUB>4</SUB> are identified, but water, polycyclic aromatic hydrocarbons and silicate features are weak or absent. The lack of small silicate grains indicates that we can look deep down into this disk. These detections testify to an active warm hydrocarbon chemistry with a high C/O ratio larger than unity in the inner 0.1 astronomical units (AU) of this disk, perhaps due to destruction of carbonaceous grains. The exceptionally high C<SUB>2</SUB>H<SUB>2</SUB>/CO<SUB>2</SUB> and C<SUB>2</SUB>H<SUB>2</SUB>/H<SUB>2</SUB>O column density ratios indicate that oxygen is locked up in icy pebbles and planetesimals outside the water iceline. This, in turn, will have important consequences for the composition of forming exoplanets.
Bettoni, G.; Leiden Observatory, Max-Planck-Institute for Extraterrestrial Physics, Garching
van Dishoeck, E. F.; Leiden Observatory, Max-Planck-Institute for Extraterrestrial Physics, Garching
Arabhavi, A. M.; University of Groningen, Kapteyn Astronomical Institute
Grant, S.; Max-Planck-Institute for Extraterrestrial Physics, Garching
Gasman, D.; Katholieke University of Leuven, Astronomical Institute
Henning, Th.; Max-Planck-Institute for Astronomy, Heidelberg
Kamp, I.; University of Groningen, Kapteyn Astronomical Institute
Güdel, M.; Max-Planck-Institute for Astronomy, Heidelberg, ETH Zurich, Department of Physics, University of Vienna, Department of Astronomy
Lagage, P. O.; CEA Saclay, Service d'Astrophysique
Ray, T.; Dublin Institute for Advanced Studies, Ireland
Vandenbussche, B.; Katholieke University of Leuven, Astronomical Institute
Abergel, A.; Institut d'Astrophysique Spatiale
Absil, Olivier ; Université de Liège - ULiège > Département d'astrophysique, géophysique et océanographie (AGO)
Argyriou, I.; Katholieke University of Leuven, Astronomical Institute
Barrado, D.; Centre for Astrobiology (CAB), CSIC-INTA, Madrid, Spain
Boccaletti, A.; Observatoire de Paris, Laboratoire d'Etudes Spatiales et d'Instrumentation en Astrophysique
Bouwman, J.; Max-Planck-Institute for Astronomy, Heidelberg
Caratti o Garatti, A.; Dublin Institute for Advanced Studies, Ireland, -
Geers, V.; Royal Observatory Edinburgh
Glauser, A. M.; ETH Zurich, Department of Physics
Justannont, K.; Chalmers University, Department of Earth and Space Sciences
Lahuis, F.; Netherlands Institute for Space Research
Mueller, M.; University of Groningen, Kapteyn Astronomical Institute
Nehmé, C.; CEA Saclay, Service d'Astrophysique
Olofsson, G.; AlbaNova University Center
Pantin, E.; CEA Saclay, Service d'Astrophysique
Scheithauer, S.; Max-Planck-Institute for Astronomy, Heidelberg
Waelkens, C.; Katholieke University of Leuven, Astronomical Institute
Waters, L. B. F. M.; Radboud University Nijmegen, Department of Astronomy and Physics, Netherlands Institute for Space Research
Black, J. H.; Chalmers University, Department of Earth and Space Sciences
Christiaens, Valentin ; Université de Liège - ULiège > Unités de recherche interfacultaires > Space sciences, Technologies and Astrophysics Research (STAR)
Guadarrama, R.; University of Vienna, Department of Astronomy
Morales-Calderón, M.; Centre for Astrobiology (CAB), CSIC-INTA, Madrid, Spain
Jang, H.; Radboud University Nijmegen, Department of Astronomy and Physics
Kanwar, J.; University of Groningen, Kapteyn Astronomical Institute, Austrian Institute of Space Science Research
Pawellek, N.; University of Vienna, Department of Astronomy, Konkoly Observatory
Perotti, G.; Max-Planck-Institute for Astronomy, Heidelberg
Perrin, A.; Laboratoire de Meteorologie Dynamique, Paris
Rodgers-Lee, D.; Dublin Institute for Advanced Studies, Ireland
Samland, M.; Max-Planck-Institute for Astronomy, Heidelberg
Schreiber, J.; Max-Planck-Institute for Astronomy, Heidelberg
Schwarz, K.; Max-Planck-Institute for Astronomy, Heidelberg
Colina, L.; Centre for Astrobiology (CAB, CSIC-INTA), Carretera de Ajalvir, Madrid, Spain
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