VENUS AND MARS ARE UNMAGNETIZED PLANETS MEANING THAT THEY DO NOT POSSESS INTRINSIC DIPOLE MAGNETIC FIELDS. SUBSEQUENTLY THE SUPERSONIC SOLAR WIND FLOW INTERACTS DIRECTLY WITH THE ATMOSPHERES AND IONOSPHERES OF BOTH BODIES FORMING INDUCED MAGNETOSPHERES THAT ACT TO DEFLECT THE SOLAR WIND FLOW AROUND THE PLANETARY OBSTACLES. THE LACK OF STRONG DIPOLE MAGNETIC FIELDS LEADS TO HIGHLY DYNAMIC AND VARIABLE PLASMA ENVIRONMENTS AT BOTH BOW SHOCKS. CONSEQUENTLY A WHOLE HOST OF LOW FREQUENCY (F ~&LT; 0.5 HZ) ELECTROMAGNETIC WAVES ARE GENERATED THAT CAN PROPAGATE THROUGH THE SHOCKS INTO THE UPPER IONOSPHERES BENEATH AND INTERACT WITH PLANETARY IONS. OUR PROPOSED STUDY WILL COMBINE DATA ANALYSIS OF FOUR SPACECRAFT DATASETS WITH GLOBAL HYBRID SIMULATIONS TO DETERMINE THE EFFECTS THAT THESE LOW FREQUENCY WAVES HAVE ON THE UPPER IONOSPHERES OF MARS AND VENUS. SPECIFICALLY WE WILL EXAMINE THE STATISTICAL CHARACTERISTICS OF OBSERVED LOW FREQUENCY WAVES QUANTIFY THE AMOUNT OF ION HEATING DRIVEN BY WAVE-PARTICLE INTERACTIONS AND DETERMINE HOW THIS HEATING INFLUENCES GLOBAL ESCAPE RATES OF PLANETARY IONS. OUR ANALYSIS IS DIRECTLY RELEVANT TO THE OBJECTIVES STATED IN THE SOLICITATION DOCUMENT C.3. MORE SPECIFICALLY OUR WORK IS RELEVANT TO UNDERSTANDING THE DYNAMICS AND STRUCTURE OF PLANETARY IONOSPHERES WITH A PARTICULAR FOCUS ON THE PHYSICAL PROCESSES THAT INFLUENCE THE ROLE OF ENERGY AND MASS TRANSFER THERE. OUR WORK WILL ALSO ADDRESS THE COUPLING OF THE IONOSPHERE TO THE MAGNETOSPHERE AND SOLAR WIND AT UNMAGNETIZED BODIES IN THE SOLAR SYSTEM. THE PROPOSED WORK INVOLVES INTERDISCIPLINARY EFFORTS (DATA ANALYSIS AND GLOBAL SIMULATIONS) TO ACHIEVE SCIENCE CLOSURE WITH A CLEAR FOCUS ON COMPARATIVE PLANETOLOGY (VENUS AND MARS). OUR PROPOSED WORK IS ALSO TIMELY IN THAT THERE ARE SEVERAL WORKING GROUPS WITHIN THE PLANETARY COMMUNITY WHO ARE ACTIVELY DEVELOPING VENUS MAGNETOSPHERE / AERONOMY MISSION PROPOSALS. OUR WORK WILL DIRECTLY INFORM THE COMMUNITY ABOUT IMPORTANT ASPECTS OF THE VENUS-SOLAR WIND INTERACTION AND WHICH NEW OBSERVATIONS AND MEASUREMENTS WOULD ENABLE THE COMMUNITY TO FURTHER DEVELOP OUR UNDERSTANDING OF THE VENUSIAN PLASMA ENVIRONMENT.