Display Settings:

Format

Send to:

Choose Destination
See comment in PubMed Commons below
Nature. 2011 Oct 5;478(7368):218-20. doi: 10.1038/nature10519.

Ocean-like water in the Jupiter-family comet 103P/Hartley 2.

Author information

  • 1Max-Planck-Institut für Sonnensystemforschung, Max-Planck-Str. 2, 37191 Katlenburg-Lindau, Germany. hartogh@mps.mpg.de

Abstract

For decades, the source of Earth's volatiles, especially water with a deuterium-to-hydrogen ratio (D/H) of (1.558 ± 0.001) × 10(-4), has been a subject of debate. The similarity of Earth's bulk composition to that of meteorites known as enstatite chondrites suggests a dry proto-Earth with subsequent delivery of volatiles by local accretion or impacts of asteroids or comets. Previous measurements in six comets from the Oort cloud yielded a mean D/H ratio of (2.96 ± 0.25) × 10(-4). The D/H value in carbonaceous chondrites, (1.4 ± 0.1) × 10(-4), together with dynamical simulations, led to models in which asteroids were the main source of Earth's water, with ≤10 per cent being delivered by comets. Here we report that the D/H ratio in the Jupiter-family comet 103P/Hartley 2, which originated in the Kuiper belt, is (1.61 ± 0.24) × 10(-4). This result substantially expands the reservoir of Earth ocean-like water to include some comets, and is consistent with the emerging picture of a complex dynamical evolution of the early Solar System.

PMID:
21976024
[PubMed]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Icon for Nature Publishing Group
    Loading ...
    Write to the Help Desk