Comets: Rosetta results and related science
Chemical composition of the surface of 67P at Agilkia
Ian Wright
Simon Sheridan, Geraint Morgan, Simeon Barber, Dan Andrews, Andrew Morse
Department of Physical Sciences, Open University, Milton Keynes, MK7 6AA, UK.
The Ptolemy instrument on board the Philae Lander (Rosetta) is a device that was designed to make elemental and isotopic measurements of the surface of comet 67P/Churyumov-Gerasimenko. Although the ultimate capability of the instrument would lie in being able to analyse a solid sample of the surface acquired by drilling, it was nevertheless pre-programmed to start so-called “sniffing” operations a few minutes after touchdown. The intention had been to gather some instant and immediate information on the status of volatiles outgassing from the landing site. In light of the non-optimal circumstances associated with the arrival at the comet’s surface, the measurements were actually made whilst in mid-flight during the “first bounce”. In principle, one might therefore have expected not to observe a significant signal. In fact, the data acquired at this time show a rich diversity of organic compounds (which are clearly of cometary origin and nothing to do with any instrument or spacecraft background/outgassing). It appears that the materials concerned probably entered the instrument as solids rather than gases. As such, we are able to report on the chemical composition of the surface of 67P at the first touchdown point (i.e. the region known as Agilkia).


13:30 - 15:00