Planetary Group Seminar: The 180/160 Oxygen Isotopic Ratio in the dust of the &/P/C-G measured by COSIMA-onboard Rosetta (J. Paquette)

The oxygen isotopic ratio ¹⁸O/¹⁶O has been measured in cometary gas for a wide variety of comets, but it has only been measured in cometary dust by Stardust. Most such measurements find a value of the ratio that is consistent with Vienna Standard Mean Ocean Water within errors. In this talk I will present the result of a measurement of the oxygen isotopic ratio in dust from Comet 67P/Churyumov-Gerasimenko with the COSIMA instrument aboard the Rosetta spacecraft. Measuring the ¹⁸O/¹⁶O ratio with COSIMA is challenging for a number of reasons, but it is possible with a reasonable degree of precision.