DPS 42nd Meeting Abs..

in characterisc velocity can be considered to be proporonal to te -0.75 , with 20-25 m/s at 100-115 s. The ‘fast’ outburst with velocies ~100 m/s probably couldconnue for at least several tens of seconds, and it could significantly increase the fracon of parcles ejected with velocies ~100 m/s compared with theexponenal decrease of velocity. The work was supported by NASA grant NNX08AG25G. [1] Ipatov S.I., A'Hearn M.F., 2010, IAU Symp. S263, 317-321. [2] IpatovS.I., A'Hearn M.F., 2010, submied to MNRAS, hp://arxiv.org/abs/0810.1294.28.36: Detecon Of Organic Compounds With COSIMA-rosea Instrument: Applicaon To PolyoxymethyleneAuthor Block: Lena Le Roy 1 , H. Con 2 , N. Fray 2 , C. Briois 3 , L. Thirkell 3 , G. Poulet 3 , M. Hilchenbach 41 LPC2E / LISA, France, 2 LISA, France, 3 LPC2E, France, 4 M PS, Germany.Presentaon Time: 10/4/2010 5:10 PM - 5:12 PMLocaon: Exhibit HallAbstract: The Rosea mission launched by ESA in March 2004 will reach the comet 67P/Churyumov-Gerasimenko in 2014 to perform the most exhausve studyever achieved on comets. A me-of-flight secondary ion mass spectrometer (TOF-SIMS), named COSIMA (COmetary Secondary Ion Mass Analyser), is onboard theRosea spacecra. It will focus on chemical analysis of solid cometary grains collected in situ. COSIMA is one of the most promising instrument in the payload ofRosea to idenfy the refractory organic molecules present on comet.Here, we focus on the detecon of a specific compound: the polyoxymethylene (POM: -(CH 2 -O) n -). Indeed POM could be at the origin of the distributed source offormaldehyde in several comets. Moreover it is produced during the irradiaon and/or thermal treatment of cometary ice analogs. It could also have played animportant role in the sugar synthesis on the primordial Earth: it is a very concentrated source of formaldehyde.We will discuss the extent to which COSIMA will be able to detect polyoxymethylene. The mass spectrum of POM has been measured using a ground analog ofCOSIMA, and we have calculated the lifeme of this polymer on cometary grains collected by COSIMA.