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

Leiden University

Max Planck Society

Marc C. van Hemert

Leiden University

John H Black

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics

Alexander G. G. M. Tielens

Leiden University

University of Maryland

A. Veselinova

University of Salamanca

P. G. Jambrina

University of Salamanca

M. Menendez

Complutense University

E. Verdasco

Complutense University

F. J. Aoiz

Complutense University

L. Gonzalez-Sanchez

University of Salamanca

Boris Trahin

University Paris-Saclay

Emmanuel Dartois

University Paris-Saclay

Olivier Berne

Paul Sabatier University

Els Peeters

Western University

SETI Institute

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

Innovative Common Laboratory For Space Spectroscopy (INCLASS)

CERGA (Centre d'Etudes et de Recherche de Grasse ACRI)

Christiaan Boersma

NASA Ames Research Center

Emeric Bron

Sorbonne University

Jan Cami

Western University

SETI Institute

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

University Paris-Saclay

Sorbonne University

Yoko Okada

University of Cologne

Takashi Onaka

Meisei University

University of Tokyo

Sofia Pasquini

Western University

Marc W. Pound

University of Michigan

Massimo Robberto

Space Telescope Science Institute (STScI)

Johns Hopkins University

Markus Roellig

Fraunhofer Institute for Applied Solid State Physics

University of Cologne

Physikalischer Verein

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

23973366 (eISSN)

Vol. 8 5 577-586

Subject Categories

Astronomy, Astrophysics and Cosmology

DOI

10.1038/s41550-024-02203-0

More information

Latest update

8/19/2024