THIS PROJECT WILL QUANTIFY THE RELATIVE CONTRIBUTION OF N+ IONS TO THE TOTAL HEAVY ION POPULATION OF THE NEAR-EARTH ENVIRONMENT. THERE HAS BEEN MUCH INTEREST IN THE TRANSPORT AND ENERGIZATION OF O+ THROUGH THE IONOSPHERE-MAGNETOSPHERE SYSTEM SINCE IT WAS FIRST REPORTED. HOWEVER RELATIVELY LITTLE HAS BEEN DONE WITH N+ EVEN THOUGH PAST OBSERVATIONS HAVE ESTABLISHED THAT N+ IS A SIGNIFICANT ION SPECIES IN THE IONOSPHERE THE SECOND MOST DOMINANT IN THE F2 REGION AND ITS PRESENCE IN THE MAGNETOSPHERE IS SIGNIFICANT. THE TRANSPORT AND ENERGIZATION OF N+ IN ADDITION TO THAT OF O+ HAVE NOT BEEN CONSIDERED BY MOST STUDIES SIMPLY BECAUSE THE OBSERVATIONAL RECORD OF ITS EXISTENCE AND SIGNIFICANCE HAS BEEN OVERLOOKED. MOST PAST MISSIONS LACKED THE POSSIBILITY TO RELIABLY DISTINGUISH THE N+ FROM O+ OWING TO THEIR VERY CLOSE MASSES AND THEREFORE WE LACK KNOWLEDGE OF THE RELATIVE CONTRIBUTION OF N+ TO THE NEAR-EARTH PLASMA POPULATION. THIS PROJECT WILL USE SIMULATIONS WITH THE SPACE WEATHER MODELING FRAMEWORK TOGETHER WITH OBSERVATIONS FROM THE MMS VAN ALLEN PROBES AND THEMIS NASA MISSIONS. WE WILL CONDUCT SIMULATIONS WITH SWMF IN VARIOUS MODEL CONFIGURATIONS AND COMPARE MODEL OUTPUT WITH THE OBSERVATIONS IN ORDER TO ASSESS THE NEAR-EARTH NONLINEAR FEEDBACK PROCESSES ON THE SPATIAL AND TEMPORAL STRUCTURE OF INNER MAGNETOSPHERIC ION COMPOSITION. DIRECT DATA-MODEL COMPARISONS WILL GRANT AN IN-DEPTH UNDERSTANDING OF THE PHYSICAL PROCESSES THAT CONTROL THE TRANSPORT AND LOSSES OF THESE HEAVY IONS THROUGHOUT THE IONOSPHERE-MAGNETOSPHERE SYSTEM ALLOWING TO QUANTIFY THEIR DISTRIBUTION AND THE LOCATION THEIR ENERGIZATION TAKES PLACE.