67P/Churyumov-Gerasimenko, a Jupiter family comet with a high D/H ratio

Kathrin Altwegg (1) , Hans Balsiger (1) , A. Bar-Nun (2) , Jean-Jacques Berthelier (3) , Andre Bieler (1, 4) , Peter Bochsler (1) , Christelle Briois (5) , Ursina Calmonte (1) , Michael Combi (4) , Johan de Keyser (6) , Peter Eberhardt (1) , Björn Fiethe (7) , Stephen Fuselier (8) , Sébastien Gasc (1) , Tamas I. Gombosi (4) , Kenneth C. Hansen (4) , Myrtha Hässig (1, 8) , Annette Jäckel (1) , Ernest Kopp (1) , A. Korth (9) , Léna Le Roy (1) , Urs Mall (9) , Bernard Marty (10) , Olivier Mousis (11) , E. Neefs (6) , Tobias Owen (12) , Henri Rème (13) , Martin Rubin (1) , Thierry Sémon (1) , Chia-Yu Tzou (1) , Hunter Waite (8) , Peter Wurz (1)

1 Physikalisches Institut [Bern]
2 TAU - Department of Geophysics [Tel Aviv]
3 PLANETO - LATMOS
4 AOSS - Department of Atmospheric, Oceanic, and Space Sciences [Ann Arbor]
5 LPC2E - Laboratoire de Physique et Chimie de l'Environnement et de l'Espace
6 BIRA-IASB - Belgian Institute for Space Aeronomy / Institut d'Aéronomie Spatiale de Belgique
7 IDA - Institute of Computer and Network Engineering [Braunschweig]
8 Space Science Division [San Antonio]
9 MPS - Max-Planck-Institut für Sonnensystemforschung
10 CRPG - Centre de Recherches Pétrographiques et Géochimiques
11 UTINAM - Univers, Transport, Interfaces, Nanostructures, Atmosphère et environnement, Molécules (UMR 6213)
12 Institute for Astronomy [Honolulu]
13 IRAP - Institut de recherche en astrophysique et planétologie

The provenance of water and organic compounds on the Earth and other terrestrial planets has been discussed for a long time without reaching a consensus. One of the best means to distinguish between different scenarios is by determining the D/H ratios in the reservoirs for comets and the Earth’s oceans. Here we report the direct in situ measurement of the D/H ratio in the Jupiter family comet 67P/Churyumov-Gerasimenko by the ROSINA mass spectrometer aboard ESA’s Rosetta spacecraft, which is found to be (5.3 ± 0.7) x 10-4, that is, ~3 times the terrestrial value. Previous cometary measurements and our new finding suggest a wide range of D/H ratios in the water within Jupiter family objects and preclude the idea that this reservoir is solely composed of Earth ocean-like water.

Domains: Sciences of the Universe [physics]; Earth Sciences; Geochemistry; Sciences of the Universe [physics]; Astrophysics [astro-ph]; Earth and Planetary Astrophysics [astro-ph.EP]

Kathrin Altwegg, Hans Balsiger, A. Bar-Nun, Jean-Jacques Berthelier, Andre Bieler, et al.. 67P/Churyumov-Gerasimenko, a Jupiter family comet with a high D/H ratio. Science, 2015, 347 (6220), 3 p. ⟨10.1126/science.1261952⟩. ⟨hal-01346024⟩