OH as a probe of the warm-water cycle in planet-forming disks
Journal article, 2024
Water is a key ingredient for the emergence of life as we know it. Yet, its destruction and reformation in space remain unprobed in warm gas (T > 300 K). Here we detect with the James Webb Space Telescope the emission of the hydroxyl radical (OH) from d203-506, a planet-forming disk exposed to external far-ultraviolet (FUV) radiation. These observations were made as part of the Early Release Science programme PDRs4All, which is focused on the Orion bar. The observed OH spectrum is compared with the results of quantum dynamical calculations to reveal two essential molecular processes. The highly excited rotational lines of OH in the mid-infrared are telltale signs of H2O destruction by FUV radiation. The OH rovibrational lines in the near-infrared are attributed to chemical excitation by the key reaction O + H-2 -> OH + H, which seeds the formation of water in the gas phase. These results show that under warm and irradiated conditions, water is destroyed and efficiently reformed through gas-phase reactions. We infer that, in this source, the equivalent of Earth oceans' worth of water is destroyed per month and replenished. This warm-water cycle could reprocess some water inherited from cold interstellar clouds and explain the lower deuterium fraction of water in Earth's oceans compared with that found around protostars.
Author
Marion Zannese
University Paris-Saclay
Benoit Tabone
University Paris-Saclay
Emilie Habart
University Paris-Saclay
Javier R. Goicoechea
CSIC - Instituto de Fisica Fundamental (IFF)
Alexandre Zanchet
CSIC - Instituto de Fisica Fundamental (IFF)
Ewine F. van Dishoeck
Max Planck Society
Leiden University
Marc C. van Hemert
Leiden University
John H Black
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
Alexander G. G. M. Tielens
University of Maryland
Leiden University
A. Veselinova
Univ Salamanca
P. G. Jambrina
Univ Salamanca
M. Menendez
Complutense University
E. Verdasco
Complutense University
F. J. Aoiz
Complutense University
L. Gonzalez-Sanchez
Univ Salamanca
Boris Trahin
University Paris-Saclay
Emmanuel Dartois
University Paris-Saclay
Olivier Berne
Paul Sabatier University
Els Peeters
Western University
Carl Sagan Ctr, SETI Inst
Jinhua He
Chinese Academy of Sciences
University of Chile (UCH)
Ameek Sidhu
Western University
Ryan Chown
Western University
Ilane Schroetter
Paul Sabatier University
Dries van de Putte
Space Telescope Science Institute (STScI)
Amelie Canin
Paul Sabatier University
Felipe Alarcon
University of Michigan
Alain Abergel
University Paris-Saclay
Edwin A. Bergin
University of Michigan
Jeronimo Bernard-Salas
INCLASS Common Lab
CERGA (Centre d'Etudes et de Recherche de Grasse ACRI)
Christiaan Boersma
NASA Ames Research Center
Emeric Bron
Sorbonne University
Jan Cami
Western University
Carl Sagan Ctr, SETI Inst
Daniel Dicken
Royal Observatory
Meriem Elyajouri
University Paris-Saclay
Asuncion Fuente
Spanish Astrobiology Center (INTA-CSIC)
Karl D. Gordon
Space Telescope Science Institute (STScI)
Ghent university
Lina Issa
Paul Sabatier University
Christine Joblin
Paul Sabatier University
Olga Kannavou
University Paris-Saclay
Baria Khan
Western University
David Languignon
Sorbonne University
Romane Le Gal
Grenoble Alpes University
Institut de Radioastronomie Millimétrique (IRAM)
Alexandros Maragkoudakis
NASA Ames Research Center
Raphael Meshaka
Sorbonne University
University Paris-Saclay
Yoko Okada
University of Cologne
Takashi Onaka
University of Tokyo
Meisei University
Sofia Pasquini
Western University
Marc W. Pound
University of Michigan
Massimo Robberto
Johns Hopkins Univ
Space Telescope Science Institute (STScI)
Markus Roellig
Physikalischer Verein
Inst Angew Phys
University of Cologne
Bethany Schefter
Western University
Thiébaut-Antoine Schirmer
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
Silvia Vicente
Institute of Astrophysics and Space Sciences (IA)
Mark G. Wolfire
University of Maryland
NATURE ASTRONOMY
2397-3366 (ISSN)
Vol. In PressSubject Categories
Astronomy, Astrophysics and Cosmology
DOI
10.1038/s41550-024-02203-0