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Updated: Sep 22, 2025

Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
COSAC's Only Gas Chromatogram Taken on Comet 67P/Churyumov-Gerasimenko
Guillaume Leseigneur1, Jan Hendrik Bredehöft2, Thomas Gautier3,4
1Université Côte d'Azur, CNRS UMR 7272, Institut de Chimie de Nice, 28 Avenue Valrose, 06108, Nice, France.
Abstract:
The Philae lander of the Rosetta space mission made a non-nominal landing on comet 67P/Churyumov-Gerasimenko on November 12, 2014. Shortly after, using the limited power available from Philae's batteries, the COSAC instrument performed a single 18-minutes gas chromatogram, which has remained unpublished until now due to the lack of identifiable elution. This work shows that, despite the unsuccessful drilling of the comet and deposition of surface material in the SD2 ovens, the measurements from the COSAC instrument were executed nominally. We describe an automated search for extremely small deviations from noise and discuss the possibility of a signal from ethylene glycol at m/z 31. Arguments for and against this detection are listed, but the results remain inconclusive. Still, the successful operations of an analytical chemistry laboratory on a cometary nucleus gives great hope for the future of space exploration.
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