High resolution X-ray observations of comets

We request 132 ks of GT to carry out observations of 6 close comets. Thesuperior sensitivity, spectral and imaging capabilities of XMM are well suitedto solving the problem of cometary Xray production, whose emission mechanism(s)is(are) unknown at this time. Six comets have been chosen to provide arepresentative sample. The observations will be complemented by amultiwavelength observational campaign. Ths comets have been chosen according toactivity, heliocentric distance and elongation.