THE FORMATION AND STABILITY PROPERTIES OF MAGNETIC FLUX ROPES ARE FUNDAMENTAL TO THE ORIGINS OF SOLAR ACTIVITY AND THE SUBSEQUENT SPACE WEATHER EVENTS. WE PROPOSE TO USE A COMBINATION OF OBSERVATIONS NONLINEAR FORCE-FREE FIELD (NLFFF) MODELS MAGNETOHYDRODYNAMIC (MHD) SIMULATIONS AND EXPERIMENTAL RESULTS TO ADDRESS THE FOLLOWING KEY SCIENCE QUESTION: WHAT GOVERNS THE STABILITY OF MAGNETIC FLUX ROPES IN THE SOLAR CORONA? IN PARTICULAR WE WILL USE NUMERICAL SIMULATIONS AS A BRIDGE BETWEEN OBSERVATIONS AND LABORATORY STUDIES OF FLUX ROPE STABILITY. WE WILL DEVELOP NLFFF MODELS OF SOLAR ACTIVE REGIONS USING THE MAGNETOFRICTIONAL METHOD. THESE MODELS WILL BE BASED ON OBSERVATIONAL DATA FROM THE HELIOSEISMIC AND MAGNETIC IMAGER (HMI) AND ATMOSPHERIC IMAGING ASSEMBLY (AIA) ON THE SOLAR DYNAMICS OBSERVATORY (SDO); THE EXTREME ULTRAVIOLET IMAGING TELESCOPE (EIT) AND MICHELSON DOPPLER IMAGER (MDI) ON THE SOLAR AND HELIOSPHERIC OBSERVATORY (SOHO); AND THE X-RAY TELESCOPE (XRT) ON HINODE. WE WILL MODEL AND ANALYZE STABLE AND UNSTABLE ACTIVE REGIONS TO INVESTIGATE HOW THE SURROUNDING MAGNETIC FIELD ENVIRONMENT AND ITS EVOLUTION IMPACT FLUX ROPE STABILITY. RECENT AND ONGOING STUDIES PERFORMED AT THE MAGNETIC RECONNECTION EXPERIMENT (MRX) AT PRINCETON PROVIDE UNIQUE INSIGHT INTO THE STABILITY OF MAGNETIC FLUX ROPES. UNLIKE REMOTE OBSERVATIONS THE MAGNETIC FIELD AND PLASMA MAY BE DIAGNOSED DIRECTLY IN ORDER TO PROVIDE A MORE THOROUGH UNDERSTANDING OF THE EVOLUTION OF FLUX ROPES. LABORATORY STUDIES ALLOW FOR EXPERIMENTAL CONTROL AND SCALING STUDIES. FORTUITOUSLY RESEARCHERS AT MRX HAVE BEEN AWARDED A DEPARTMENT OF ENERGY GRANT TO EXPERIMENTALLY INVESTIGATE THE STABILITY PROPERTIES OF MAGNETIC FLUX ROPES OVER THE NEXT THREE YEARS. WE THEREFORE HAVE THE OPPORTUNITY TO LINK THESE EXPERIMENTAL STUDIES WITH SOLAR OBSERVATIONS. WE WILL PERFORM A TWO-PRONGED SIMULATION EFFORT BY SIMULATING FLUX ROPES IN LABORATORY EXPERIMENTS AND IN SOLAR ACTIVE REGIONS. WE WILL USE THE NLFFF MODELS THAT BEST MATCH OBSERVATIONS AS INITIAL CONDITIONS FOR MHD NUMERICAL SIMULATIONS. WE WILL PERFORM SIMULATIONS OF FLUX ROPE EXPERIMENTS IN MRX. WE WILL USE EACH OF THESE SIMULATIONS TO STUDY HOW THE MAGNETIC FIELD STRUCTURE IMPACTS STABILITY IN BOTH CASES AND SYNTHESIZE THE RESULTS TO UNDERSTAND THE IMPLICATIONS OF THE EXPERIMENTAL RESULTS ON THE STABILITY OF ACTIVE REGIONS. THE PROPOSED EFFORT WILL ADDRESS THE HELIOPHYSICS DECADAL SURVEY KEY SCIENCE GOAL TO "DETERMINE THE ORIGINS OF THE SUN'S ACTIVITY AND PREDICT THE VARIATIONS IN THE SPACE ENVIRONMENT" BY INVESTIGATING THE STABILITY PROPERTIES OF ACTIVE REGIONS AND CONNECTING EXPERIMENTAL AND OBSERVATIONAL STUDIES USING NUMERICAL SIMULATIONS. THE PROPOSED EFFORT WILL ADDRESS THE DECADAL SURVEY'S KEY SCIENCE GOAL TO "DISCOVER AND CHARACTERIZE FUNDAMENTAL PROCESSES THAT OCCUR BOTH WITHIN THE HELIOSPHERE AND THROUGHOUT THE UNIVERSE" BY INVESTIGATING FLUX ROPE INSTABILITIES.