Reference frames and mapping schemes of comet 67 P

To establish compatibility among derived data and scientific results, the intention of this document is to propose a set of rotational parameters of 67P that defines a common reference frame for the variety of applications within the OSIRIS team, as well as a proposal for common use within the entire Rosetta team. The proposed definitions are in agreement with different investigations within the OSIRIS 3D group and respective results from OSIRIS NAC analyses using different image processing approaches, i.e. stereo-photogrammetry (SPG, [A2]) and stereo-photoclinometry (SPC, [A3,A4]). The proposal also considers results from other investigations outside the OSIRIS team, specifically stereo analysis and landmark tracking using NAVCAM and OSIRIS WAC images (STR, [A5a,b]). The following definition of reference frames and rotation parameters is based upon analyses of images that have been acquired during August and September 2014. Thus, and particularly because of the unpredictable stability of the rotation of a comet nucleus, the relevance of all definitions is limited to this time period and will be subject to continuing investigations and further refinements.