First insights on the organic species from the high resolution mass spectrometer ROSINA DFMS on-board the Rosetta spacecraft

Thursday, 18 December 2014
Lena Le Roy1, Kathrin Altwegg1, Jean-Jacques Berthelier2, Ursina Calmonte1, Frederik Dhooghe3, Bjoern Fiethe4, Stephen Fuselier5, Tamas I Gombosi6, Martin Rubin1 and Chia-yu Tzou1, (1)University of Bern, Bern, Switzerland, (2)LATMOS Laboratoire Atmosphères, Milieux, Observations Spatiales, Paris Cedex 05, France, (3)Belgian Institute for Space Aeronomy, Brussels, Belgium, (4)Technical University of Braunschweig, Braunschweig, Germany, (5)Southwest Research Institute San Antonio, San Antonio, TX, United States, (6)Univ of Michigan, Ann Arbor, MI, United States
Starting in August 2014, the ROSINA experiment will characterize the composition and dynamics of 67P/Churyumov-Gerasimenko’s coma. ROSINA consists of a suite of three instruments: a pressure sensor (COPS: COmetary Pressure Sensor) and two mass spectrometers: the Reflectron Time of Flight mass spectrometer (RTOF) and the Double Focusing Mass Spectrometer (DFMS). Here we will focus on the first results obtained by DFMS, the high-resolution mass spectrometer of ROSINA. DFMS is a traditional magnetic mass spectrometer that combines an electrostatic analyzer for energy analysis with a magnet for momentum analysis. To date, DFMS is the highest mass resolution mass spectrometer in space, with resolution (m/Δm = 3000 at 1% of the peak height at 28 amu/q). It will be able to resolve CO from N2 at m/z= 28 amu/q or 12CH and 13C at m/z= 13 amu/q. We will present the first results of DFMS: the detection of organic species and their implication for the origin of cometary material.