ATTENUATION AND FLOW/RELAXATION IN ICE-I AND ITS EFFECT ON THERMOMECHANICAL EVOLUTION OF THE ICY SATELLITESTHE ENERGY BUDGET OF THE ICY SATELLITES DEPENDS TO FIRST ORDER ON THE CONVERSION OF TIDAL ENERGY INTO HEAT WHICH IS EFFECTED BY THE THERMOPHYSICAL PROPERTY OF MATERIALS KNOWN AS ANELASTICITY OR ATTENUATION. THE RECENT DISCOVERY OF PLUMES ERUPTING FROM EUROPA S SOUTH POLE REVEALS NOT ONLY THAT THE MOON IS MORE GEOLOGICALLY ACTIVE THAN EXPECTED BUT THAT THE THEORETICAL MODELS IMPLYING THE MOON S QUIESCENCE ARE INACCURATE -AN INACCURACY PREDICATED SPECIFICALLY ON A LACK OF EXTRAPOLATIVE MODELS OF VISCOELASTICITY (CREEP AND ATTENUATION COMBINED) IN POLYCRYSTALLINE ICE-I. PRESENT RHEOLOGICAL EXTRAPOLATIONS FOR ATTENUATION ARE PREDICATED ON A MODEL SPECIFICALLY DIFFUSIONAL CREEP GIVING RISE TO A SIMPLE MAXWELL VISCOSITY WHICH LABORATORY EXPERIMENTS HAVE DEMONSTRATED AS CLEARLY INAPPROPRIATE. SOUND DEFENSIBLE EXTRAPOLATIONS CAN ONLY BE DONE FROM EXPERIMENTS PROBING THE SAME PHYSICAL MECHANISMS OPERATIVE WITHIN AN ICY SATELLITE. WE PROPOSE A UNIQUE EXPERIMENTAL/THEORETICAL STUDY SPECIFICALLY TO ADDRESS THIS NEED. ENGINEERED ICE- I SPECIMENS OF CONTROLLED GRAIN SIZE AND IMPURITY CONTENT WILL BE SUBJECTED TO SIMULTANEOUS LOADING FOR STEADY-STATE CREEP (CONSTANT MEAN DIFFERENTIAL STRESS ~0.5MPA) AND ATTENUATION (SINUSOID ABOUT THE MEAN STRESS ~ 0.05MPA AND 1E-4<(HZ)<1) AT 200<T(K)<255). THESE ARE CONDITIONS CONSISTENT WITH PLANETARY ICE PHYSICS AS PRESENTLY UNDERSTOOD WITH A RHEOLOGY WHEREBY LATTICE DISLOCATIONS AND DIFFUSION-AFFECTED GRAIN BOUNDARY SLIDING BOTH CONTRIBUTE TO EFFECTIVE VISCOSITY AND ATTENUATION. DEFORMED SPECIMENS WILL BE EVALUATED MICROSTRUCTURALLY VIA DIFFERENTIAL INTERFERENCE CONTRAST (NOMARSKI) OPTICAL MICROSCOPY. THEORETICALLY THERE ARE TWO THRUSTS: (1) APPLICATION OF EQUATION-OF-STATE RHEOLOGY THEORY TO ATTENUATION AND (2) PARAMETERIZATION OF A VISCOELASTIC RHEOLOGY CONSISTENT WITH THAT DISCERNED IN THESE EXPERIMENTS THAT CAN BE APPLIED TO MODELS OF ENERGY BUDGET AND DEFORMATION ON ICY SATELLITES. IMPURITY CONTENT WILL EMPHASIZE SALTS (SULFATE AND AMMONIUM PRIMARILY) PARTICULARLY INCLUDING SECOND PHASES OF SALT HYDRATES. THE EXPERIMENTS ADDITIONALLY ALLOW CHARACTERIZATION OF TRANSIENT CREEP RESPONSES TO SIGNIFICANT STAINS (I.E. >0.01) I.E. THOSE THAT AFFECT MICROSTRUCTURAL CHANGES IN THE RESISTANCE TO FLOW; THESE DATA CAN BE USED TO ADDRESS THE PHYSICS OF SURFACE RELAXATION ON THE SATELLITES. STATEMENT OF THE PERCEIVED SIGNIFICANCE OF THE PROPOSED WORK TO THE OBJECTIVES OF THE SOLICITATION AND TO NASA INTERESTS AND PROGRAMS IN GENERAL: THE MISSION TO EUROPA WILL BE ABLE TO MONITOR THE SATELLITE'S GEOID BUT HOW IS THAT TURNED IN TO AN ENERGY BUDGET? PRESENT COMPREHENSION OF MECHANICAL RESPONSE OF ICE IS RAPIDLY CHANGING AND THE PROPOSED EXPERIMENTS AND ANALYSES WILL BE CRUCIAL TO THE APPROPRIATE INTERPRETATION OF MISSION DATA. MORE GENERALLY THE PROPOSED WORK IS DISTINCTLY RELEVANT TO THE NASA SOLAR SYSTEMS WORKINGS PROGRAM SPECIFICALLY IN THAT THE CALL SEEKS TO ADDRESS THE PHYSICAL AND CHEMICAL PROCESSES THAT AFFECT THE SURFACES INTERIORS OF PLANETARY BODIES AND PARTICULARLY LABORATORY AND THEORETICAL STUDIES GEARED TOWARDS UNDERSTANDING INTERNAL STRUCTURE CHEMISTRY AND DYNAMICS OF SOLAR-SYSTEM BODIES.