THE PRIMARY GOAL OF THE MAGNETOSPHERIC MULTISCALE (MMS) MISSION IS TO LEARN HOW THE SOLAR AND TERRESTRIAL MAGNETIC FIELDS CONNECT OR DISCONNECT AND EXPLOSIVELY TRANSFER ENERGY FROM ONE TO THE OTHER IN A PROCESS CALLED MAGNETIC RECONNECTION THAT IS IMPORTANT EVERYWHERE IN THE UNIVERSE. THE SUCCESS OF THE MMS MISSION IS CRITICAL TO NASA AND HELIOPHYSICS BECAUSE RECONNECTION IS THE UNDERLYING PHYSICAL PROCESS RESPONSIBLE FOR THE RELEASE OF ENERGY STORED IN MAGNETOSPHERIC MAGNETIC FIELDS THAT POWERS PLASMA HEATING AND ACCELERATION DURING SOLAR AND GEOMAGNETIC STORMS. GIVEN THE CENTRAL ROLE BELIEVED TO BE PLAYED BY PLASMOIDS (I.E. MAGNETIC ISLANDS IN 2-D AND FLUX ROPES IN 3-D) IN THE DEVELOPMENT OF FAST MAGNETIC RECONNECTION THE ACHIEVEMENT OF MMSS OVERARCHING GOAL TO UNDERSTAND MAGNETIC RECONNECTION AND HOW IT RECONFIGURES AND ENERGIZES CORONAL AND MAGNETOSPHERIC PLASMAS WILL ALSO REQUIRE DISCOVERING HOW FLUX ROPES FORM GROW AND DISSIPATE. WE PROPOSE TO USE THE MMS HIGH-RESOLUTION PARTICLES AND FIELDS MEASUREMENTS TO ANSWER THE FOLLOWING QUESTIONS CONCERNING FLUX ROPES IN THE PLASMA SHEET: A) WHAT ARE THE PHYSICAL PROPERTIES OF ION-INERTIAL SCALE (10**2 KM) FLUX ROPES? 1. HOW DO ION-INERTIAL SCALE FLUX ROPES IN THE MMS OBSERVATIONS DIFFER STRUCTURALLY FROM THE ~ 1 TO 10 EARTH RADII (10**4-5 KM) ROPES STUDIED BY GEOTAIL AND CLUSTER (E.G. DIAMETER ORIENTATION MAGNETIC FLUX CONTENT CORE FIELD MAGNITUDE ETC.)? 2. HOW DO THE PLASMA POPULATIONS VARY FROM THE STRONG MAGNETIC FIELD CORES OF THE FLUX ROPES TO THEIR OUTER LAYERS? WHAT DO THE PITCH ANGLE DISTRIBUTIONS TELL US ABOUT THE TRANSPORT INTO/OUT OF THE FLUX ROPE AND ITS MAGNETIC CONNECTIVITY TO EARTH THE MAGNETOTAIL AND POSSIBLY THE SOLAR WIND? 3. ARE CHAINS OF ION SCALE FLUX ROPES OBSERVED? WHAT ARE THEIR PHYSICAL PROPERTIES AND SEPARATIONS? WHAT FACTORS CONTROL THE SEPARATIONS AND OTHER ASPECTS OF THE CHAINS? 4. TO WHAT DEGREE ARE THESE ION-SCALE FLUX ROPES FORCE-FREE (I.E. J X B ~ 0)? DO THEY SHOW EVIDENCE FOR CONTRACTION OR EXPANSION AS A RESULT OF CHANGING INTERNAL STRUCTURE AND EXTERNAL PRESSURE? WHAT FRACTION OF THE FLUX ROPES HAVE RELAXED INTO THEIR MINIMUM ENERGY STATE VERSUS THOSE STILL EVOLVING FROM THEIR FORMATION STATE OR DUE TO EXTERNAL INPUTS? B) HOW ION-INERTIAL SCALE FLUX ROPES EVOLVE WITH TIME AND BY INTERACTION WITH THEIR SURROUNDINGS? 1. DO ION-SCALE FLUX ROPES GROW PRIMARILY THROUGH MAGNETIC FLUX ADDED THROUGH CONTINUED RECONNECTION AT X-LINES OR BY MERGING WITH OTHER FLUX ROPES (I.E. COALESCENCE)? WHAT ARE THE RELATIVE RATES OF FLUX ADDITION FOR THESE TWO PROCESSES? 2. IS CHARGED PARTICLE ENERGIZATION OBSERVED WITHIN THE FLUX ROPES? IF SO THEN WHAT ARE THE MECHANISMS RESPONSIBLE FOR PARTICLE HEATING AND ACCELERATION. 3. DO EARTHWARD MOVING FLUX ROPES EVENTUALLY DISSIPATE THROUGH RECONNECTION WITH THE GEOMAGNETIC FIELD? WHAT IS THE RATE OF DISSIPATION AS A FUNCTION OF EXTERNAL MAGNETIC FIELD AND PLASMA CONDITIONS? OUR APPROACH WILL USE COMBINATION OF SINGLE- AND MULTI-SPACECRAFT DATA ANALYSIS TECHNIQUES DEVELOPED TO DETERMINE THE PHYSICAL PROPERTIES OF THE MAGNETIC FLUX ROPES AND COMPARE THE RESULTS AGAINST PUBLISHED PARTICLE-IN-CELL AND HYBRID SIMULATION RESULTS. THE RESULTS OF OUR RESEARCH WILL CONTRIBUTE TO THE MMS MISSIONS PRIMARY SCIENCE GOAL ... TO PROBE RECONNECTION OF SOLAR AND TERRESTRIAL MAGNETIC FIELDS IN THE DAYSIDE AND NIGHTSIDE OF EARTHS MAGNETOSPHERE ... AND ... (TO) PROVIDE KNOWLEDGE OF A UNIVERSAL PROCESS (RECONNECTION) THAT IS THE FINAL GOVERNOR OF SPACE WEATHER ... THE RESEARCH WILL ALSO CONTRIBUTE TO THE HELIOPHYSICS DECADAL SURVEY GOAL #2 DETERMINE THE DYNAMICS AND COUPLING OF EARTHS MAGNETOSPHERE IONOSPHERE AND ATMOSPHERE AND THEIR RESPONSE TO SOLAR AND TERRESTRIAL INPUTS.