Sampling the solar wind on its way from solar max to solar min in 3D with comets

We propose to utilize comets as natural space probes for sampling the heavy ioncontent of the solar wind in the transition phase from solar maximum to solarminimum in 3D, by investigating the Xray emission which results from chargeexchange interactions between solar wind ions and cometary neutrals. DuringAO14, three comets will be favorably placed for XMMNewton: C/2013 US10(Catalina), 252P/LINEAR, and 67P/ChuryumovGerasimenko, sampling the solar windbetween 30 deg and +30 deg heliographic latitude. This proposal makes full useof the spectral, temporal, and spatial resolution of XMMNewton, of its fullfield of view, and of all its six (PN, MOS1, MOS2, RGS1, RGS2, OM) scientificinstruments. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]