RSI RSI (Radio Science Investigation). Shifts in the spacecraft's radio signals are used to measure the mass, density and gravity of the nucleus, to define the comet's orbit, and to study the inner coma. RSI will also be used to measure the mass and density of Siwa, and to study the solar corona during the periods when the spacecraft, as seen from Earth, is passing behind the Sun.   Principal Investigator: M. Pätzold, University of Cologne, Cologne, Germany.       Last update: 21 January 2004  •  Rosetta at a glance (http://www.esa.int/SPECIALS/Rosetta/SEMYMF374OD_0.html)  •  The Rosetta orbiter (http://www.esa.int/SPECIALS/Rosetta/ESAHVF7708D_0.html)  •  The Rosetta lander (http://www.esa.int/SPECIALS/Rosetta/ESAMXF7708D_0.html) Instruments on the orbiter  •  ALICE (http://www.esa.int/SPECIALS/Rosetta/SEMRHF374OD_0.html)  •  CONSERT (http://www.esa.int/SPECIALS/Rosetta/SEMUQ0474OD_0.html)  •  COSIMA (http://www.esa.int/SPECIALS/Rosetta/SEMCM0474OD_0.html)  •  GIADA (http://www.esa.int/SPECIALS/Rosetta/SEM0T0474OD_0.html)  •  MIDAS (http://www.esa.int/SPECIALS/Rosetta/SEMGO0474OD_0.html)  •  MIRO (http://www.esa.int/SPECIALS/Rosetta/SEMXPZ374OD_0.html)  •  OSIRIS (http://www.esa.int/SPECIALS/Rosetta/SEMYCF374OD_0.html)  •  ROSINA (http://www.esa.int/SPECIALS/Rosetta/SEM5K0474OD_0.html)  •  RPC (http://www.esa.int/SPECIALS/Rosetta/SEMUV0474OD_0.html)  •  VIRTIS (http://www.esa.int/SPECIALS/Rosetta/SEM28Q374OD_0.html) Instruments on the lander  •  APXS (http://www.esa.int/SPECIALS/Rosetta/SEMBU5474OD_0.html)  •  ÇIVA (http://www.esa.int/SPECIALS/Rosetta/SEMZU5474OD_0.html)  •  CONSERT (http://www.esa.int/SPECIALS/Rosetta/SEM2W5474OD_0.html)  •  COSAC (http://www.esa.int/SPECIALS/Rosetta/SEMPW5474OD_0.html)  •  MODULUS PTOLEMY (http://www.esa.int/SPECIALS/Rosetta/SEMDX5474OD_0.html)  •  MUPUS (http://www.esa.int/SPECIALS/Rosetta/SEMOX5474OD_0.html)  •  ROLIS (http://www.esa.int/SPECIALS/Rosetta/SEMIY5474OD_0.html)  •  ROMAP (http://www.esa.int/SPECIALS/Rosetta/SEMTY5474OD_0.html)  •  SD2 (http://www.esa.int/SPECIALS/Rosetta/SEM5Z5474OD_0.html)  •  SESAME (http://www.esa.int/SPECIALS/Rosetta/SEMGZ5474OD_0.html)