WE SEEK FUNDS TO CONTINUE THE ACQUISITION OF HIGH-PRECISION ROTATION MEASUREMENTS OF VENUS AND THE GALILEAN SATELLITES WITH A POWERFUL EARTH-BASED RADAR TECHNIQUE. THE ROTATIONAL RESPONSE OF PLANETARY BODIES TO A VARIETY OF FORCINGS PROVIDES FUNDAMENTAL INSIGHTS INTO THEIR INTERIOR STRUCTURE AND RHEOLOGY THEIR DYNAMICAL AND THERMAL EVOLUTION AND THE MAJOR GEOPHYSICAL PROCESSES THAT AFFECT ROTATION SUCH AS ENERGY DISSIPATION IN THE INTERIOR CORE-MANTLE AND SHELL-OCEAN INTERACTIONS AND ATMOSPHERIC DYNAMICS. OUR SPECIFIC OBJECTIVES ARE: (1) TO OBTAIN HIGH-PRECISION (10 PPM) MEASUREMENTS OF THE SPIN RATE OF VENUS IN ORDER TO QUANTIFY DAILY SEASONAL AND SECULAR CHANGES IN THE LENGTH OF DAY AND TO PROVIDE A TIME HISTORY OF ATMOSPHERIC ANGULAR MOMENTUM VARIATIONS IN ORDER TO PROBE ATMOSPHERIC DYNAMICS; (2) TO MEASURE THE ORIENTATION OF THE SPIN AXIS OF VENUS WITH<5" PRECISION THE SPIN PRECESSION RATE AND THE POLAR MOMENT OF INERTIA WITH 10% UNCERTAINTIES; (3) TO OBTAIN MEASUREMENTS OF THE OBLIQUITIES OF EUROPA AND GANYMEDE WITH 10% PRECISION. THIS INVESTIGATION WILL RELY ON OBSERVATIONS OF THE RADAR SPECKLE DISPLACEMENT EFFECT A METHOD THAT HAS BEEN VALIDATED AT THE 1% LEVEL BY MESSENGER OBSERVATIONS. THE PROPOSED INVESTIGATION DIRECTLY ADDRESSES SCIENCE QUESTIONS FORMULATED BY NASA'S PLANETARY SCIENCE DIVISION: (1) "HOW DID THE SOLAR SYSTEM EVOLVE TO ITS CURRENT DIVERSE STATE?" (2) "WHAT ARE THE CHARACTERISTICS OF THE SOLAR SYSTEM THAT LEAD TO THE ORIGINS OF LIFE?" THIS INVESTIGATION FALLS WITHIN THE SCOPE OF THE PLANETARY ASTRONOMY (PAST) PROGRAM ELEMENT BECAUSE IT CENTERS ON NEW SOLAR SYSTEM OBSERVATION AND BECAUSE IT SUPPORTS THOSE NASA SOLAR SYSTEM PROGRAM OBJECTIVES THAT CANNOT BE MET BY CURRENT SPACECRAFT MISSIONS OR THAT DIRECTLY SUPPORT SPECIFIC FLIGHT MISSIONS (E.G. EUROPA CLIPPER). BECAUSE THE PROPOSED INVESTIGATION IS RESPONSIVE TO THE PRIMARY GOAL OF THE PAST PROGRAM ELEMENT AND NOT DIRECTLY RESPONSIVE TO GOALS OF OTHER PROGRAM ELEMENTS THE PAST PROGRAM ELEMENT IS THE MOST APPROPRIATE FOR THE WORK PROPOSED.