DLR-Logo -> http://www.dlr.de
DLR Portal Home | Imprint | Privacy Policy | Contact | Deutsch
Fontsize: [-] Text [+]

Decay of COSAC and Ptolemy mass spectra at comet 67P/Churvumov-Gerasimenko

Krüger, Harald and Goesmann, Fred and Giri, Chaitanya and Wright, Ian and Morse, Andrew and Bredehöft, Jan Hendrik and Ulamec, Stephan and Cozzoni, Barbara and Ehrenfreund, Pascale and Gautier, Thomas and McKenna-Lawlor, Susan and Raulin, François and Steiniger, Harald and Stopa, Cyril (2017) Decay of COSAC and Ptolemy mass spectra at comet 67P/Churvumov-Gerasimenko. Astronomy & Astrophysics (A56), pp. 1-7. EDP Sciences. DOI: 10.1051/0004-6361/201630286 ISSN 0004-6361

[img] PDF


Context. The Rosetta lander Philae successfully landed on the nucleus of comet 67P/Churyumov-Gerasimenko on 12 November 2014. Philae is equipped with two gas analysers: The Cometary Sampling and Composition experiment (COSAC) and the gas chromatograph and mass spectrometer Ptolemy. Aims. COSAC is designed for in situ analysis of organic molecules on 67P while Ptolemy is optimised to measure ratios of stable isotopes. Methods. On 12 to 14 November 2014, both instruments measured the organic composition of the comet nucleus material through seven measurements in sniffing mode during Philae’s hopping and at its final landing site Abydos. We compare the temporal evolution of intensities of several ion species identified by both mass spectrometers. For COSAC, this is the first analysis of the temporal behaviour of the measured ion species. Results. All ion species showed the highest intensities in the first spectra measured by both instruments approximately 20 to 30 min after Philae’s first touchdown at Agilkia, and a decay during the six consecutive measurements at Abydos. Both instruments measured an almost identical decay of the water peak (m/z 18), and CO (m/z 28) behaved similarly. In the COSAC measurements, the peak at m/z 44 decays much slower than all the other ion species, including the water peak. In particular, the m/z 44 peak decays much slower in the COSAC measurements than in the Ptolemy data. This supports our earlier interpretation that COSAC analysed, for the first time, a regolith sample from a cometary nucleus in situ, while Ptolemy measured cometary gas from the ambient coma. The m/z 44 peak measured by COSAC was likely dominated by organic species, whereas the peak measured by Ptolemy was interpreted to be mostly due to CO2. Ion specues heavier thant m/z 30 tend to decay somewhat slower in the in the COSAC measurements than in the Ptolemy data, which may be related to differences in the exhaust designs between both instruments.

Item URL in elib:https://elib.dlr.de/111792/
Document Type:Article
Title:Decay of COSAC and Ptolemy mass spectra at comet 67P/Churvumov-Gerasimenko
AuthorsInstitution or Email of AuthorsAuthors ORCID iD
Krüger, HaraldMax-Planck-Institut für Sonnensystemforschung, Göttingen GermanyUNSPECIFIED
Goesmann, FredMax-Planck-Institut für Sonnensystemforschung, Göttingen GermanyUNSPECIFIED
Giri, ChaitanyaTokyo Instiutt of Technology & Max-Planck-Institut für Sonnensystemforschung, Göttingen GermanyUNSPECIFIED
Wright, IanThe Open University Milton KeynesUNSPECIFIED
Morse, AndrewThe Open University Milton KeynesUNSPECIFIED
Bredehöft, Jan HendrikUniversität BremenUNSPECIFIED
Ulamec, StephanDLR Köln, stephan.ulamec (at) dlr.deUNSPECIFIED
Cozzoni, Barbaradlr-köln, barbara.cozzoni (at) dlr.deUNSPECIFIED
Ehrenfreund, PascaleLeiden Institute of Chemistry & George Washington UniversityUNSPECIFIED
Gautier, ThomasPHM Marseille & Universities Space Reserach Association - GreenbeltUNSPECIFIED
McKenna-Lawlor, Susanspace technology ireland, national university of ireland maynooth, co. kildare, irelandUNSPECIFIED
Raulin, FrançoisLISA, Université Paris-EstUNSPECIFIED
Steiniger, HaraldMax-Planck-Institut für Sonnensystemforschung, Göttingen GermanyUNSPECIFIED
Stopa, CyrilUniversité VersaillesUNSPECIFIED
Date:January 2017
Journal or Publication Title:Astronomy & Astrophysics
Refereed publication:Yes
Open Access:Yes
Gold Open Access:No
In ISI Web of Science:Yes
DOI :10.1051/0004-6361/201630286
Page Range:pp. 1-7
Publisher:EDP Sciences
Keywords:astrochemistry, comets: individual: 67P/Churyumov-Gerasimenko - comets: General, astrobiology, space vehicles: instruments
HGF - Research field:Aeronautics, Space and Transport
HGF - Program:Space
HGF - Program Themes:Space Science and Exploration
DLR - Research area:Raumfahrt
DLR - Program:R EW - Erforschung des Weltraums
DLR - Research theme (Project):R - Projekt ROSETTA Lander
Location: Köln-Porz
Institutes and Institutions:Space Operations and Astronaut Training > User center for space experiments (MUSC)
Deposited By: Herrmann, Astrid
Deposited On:10 Apr 2017 15:37
Last Modified:31 Jul 2019 20:09

Repository Staff Only: item control page

Help & Contact
electronic library is running on EPrints 3.3.12
Copyright © 2008-2017 German Aerospace Center (DLR). All rights reserved.