Astrophysics - Earth and Planetary Astrophysics; Astrophysics - Solar; and Stellar Astrophysics
Abstract :
[en] Terrestrial and sub-Neptune planets are expected to form in the inner (less than 10 AU) regions of protoplanetary disks<SUP>1</SUP>. Water plays a key role in their formation<SUP>2-4</SUP>, although it is yet unclear whether water molecules are formed in situ or transported from the outer disk<SUP>5,6</SUP>. So far Spitzer Space Telescope observations have only provided water luminosity upper limits for dust-depleted inner disks<SUP>7</SUP>, similar to PDS 70, the first system with direct confirmation of protoplanet presence<SUP>8,9</SUP>. Here we report JWST observations of PDS 70, a benchmark target to search for water in a disk hosting a large (approximately 54 AU) planet-carved gap separating an inner and outer disk<SUP>10,11</SUP>. Our findings show water in the inner disk of PDS 70. This implies that potential terrestrial planets forming therein have access to a water reservoir. The column densities of water vapour suggest in-situ formation via a reaction sequence involving O, H<SUB>2</SUB> and/or OH, and survival through water self-shielding<SUP>5</SUP>. This is also supported by the presence of CO<SUB>2</SUB> emission, another molecule sensitive to ultraviolet photodissociation. Dust shielding, and replenishment of both gas and small dust from the outer disk, may also play a role in sustaining the water reservoir<SUP>12</SUP>. Our observations also reveal a strong variability of the mid-infrared spectral energy distribution, pointing to a change of inner disk geometry.
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Perotti, G.; Max-Planck-Institute for Astronomy, Heidelberg
Christiaens, Valentin ; Université de Liège - ULiège > Unités de recherche interfacultaires > Space sciences, Technologies and Astrophysics Research (STAR)
Henning, Th.; Max-Planck-Institute for Astronomy, Heidelberg
Tabone, B.; Institut d'Astrophysique Spatiale
Waters, L. B. F. M.; Radboud University Nijmegen, Department of Astronomy and Physics, Netherlands Institute for Space Research
Kamp, I.; Kapteyn Astronomical Institute, Rijksuniversiteit Groningen, Groningen, the Netherlands
Olofsson, G.; AlbaNova University Center
Grant, S. L.; Max-Planck-Institute for Extraterrestrial Physics, Garching
Gasman, D.; Katholieke University of Leuven, Astronomical Institute
Bouwman, J.; Max-Planck-Institute for Astronomy, Heidelberg
Samland, M.; Max-Planck-Institute for Astronomy, Heidelberg
Franceschi, R.; Max-Planck-Institute for Astronomy, Heidelberg
van Dishoeck, E. F.; Max-Planck-Institute for Extraterrestrial Physics, Garching, Leiden Observatory
Schwarz, K.; Max-Planck-Institute for Astronomy, Heidelberg
Güdel, M.; Max-Planck-Institute for Astronomy, Heidelberg, -, ETH Zurich, Department of Physics
Lagage, P. -O.; CEA Saclay, Service d'Astrophysique
Ray, T. P.; 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)
Arabhavi, A. M.; Kapteyn Astronomical Institute, Rijksuniversiteit Groningen, Groningen, the Netherlands
Argyriou, I.; Katholieke University of Leuven, Astronomical Institute
Barrado, D.; Centro de Astrobiología (CAB), CSIC-INTA, Villanueva de la Cañada, Spain
Boccaletti, A.; Observatoire de Paris, Laboratoire d'Etudes Spatiales et d'Instrumentation en Astrophysique
Caratti o Garatti, A.; Dublin Institute for Advanced Studies, Ireland, Astronomical Observatory of Capodimonte
Geers, V.; Royal Observatory Edinburgh
Glauser, A. M.; ETH Zurich, Department of Physics
Justannont, K.; Onsala Space Observatory
Lahuis, F.; Netherlands Institute for Space Research
Mueller, M.; Kapteyn Astronomical Institute, Rijksuniversiteit Groningen, Groningen, the Netherlands
Nehmé, C.; CEA Saclay, Service d'Astrophysique
Pantin, E.; CEA Saclay, Service d'Astrophysique
Scheithauer, S.; Max-Planck-Institute for Astronomy, Heidelberg
Waelkens, C.; Katholieke University of Leuven, Astronomical Institute
Guadarrama, R.; Dept. of Astrophysics, University of Vienna, Vienna, Austria
Jang, H.; Radboud University Nijmegen, Department of Astronomy and Physics
Kanwar, J.; Kapteyn Astronomical Institute, Rijksuniversiteit Groningen, Groningen, the Netherlands, Space Research Institute, Austrian Academy of Sciences, Graz, Austria, TU Graz, Fakultät für Mathematik, Physik und Geodäsie, Graz, Austria
Morales-Calderón, M.; Centro de Astrobiología (CAB), CSIC-INTA, Villanueva de la Cañada, Spain
Pawellek, N.; Dept. of Astrophysics, University of Vienna, Vienna, Austria
Rodgers-Lee, D.; Dublin Institute for Advanced Studies, Ireland
Schreiber, J.; Max-Planck-Institute for Astronomy, Heidelberg
Colina, L.; Centro de Astrobiología (CAB, CSIC-INTA), Carretera de Ajalvir, Torrejón de Ardoz, Spain
Greve, T. R.; DTU Physics, Lyngby
Östlin, G.; Stockholm University, Department of Astronomy
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