WHETHER MAGNETIC RECONNECTION OCCURS AT WIDELY SEPARATED SINGLE X-LINES IN THE SOLAR WIND OR VIA MORE CLOSELY SPACED MULTIPLE X-LINES THAT FORM MAGNETIC FLUX ROPES IS A TOPIC OF GREAT IMPORTANCE FOR OUR UNDERSTANDING OF SOLAR WIND STRUCTURE AND ULTIMATELY ITS ENERGY BUDGET. IDENTIFYING RECONNECTION-RELATED 5-1000 DI SCALE (1 DI=C/WPI) FLUX ROPES AT SOLAR WIND CURRENT SHEETS (CS) IS A CHALLENGE USING SPACECRAFT OBSERVATIONS. WE RECENTLY REPORTED AN APPARENT MAGNETIC ISLAND-INDUCED TRIPOLAR PERTURBATION OF THE OUT-OF-PLANE (GUIDE) MAGNETIC FIELD (BM) ACROSS A SOLAR WIND EXHAUST. IT CONSISTS OF A BM MAGNITUDE INCREASE AT THE CENTER OF THE CS AND TWO ADJACENT BM MAGNITUDE DIPS. A TRIPOLAR BM WAS ABSENT ACROSS A SIMULATED CS WITH A SINGLE X-LINE (NO ISLANDS). PRELIMINARY PIC SIMULATIONS IN 2D FOR DIFFERENT GUIDE FIELDS SHOW THAT TRIPOLAR BM SIGNATURES DEVELOP NEAR MAGNETIC ISLANDS OF A TEARING UNSTABLE CS FOR BM=BL WHERE BL IS THE RECONNECTING FIELD WHILE IT IS ABSENT FOR A WEAK BM/BL=0.1 WHEN BIPOLAR HALL MAGNETIC FIELDS INSTEAD DOMINATE GUIDE FIELD CHANGES ACROSS EXHAUSTS. A PRELIMINARY 3D PIC SIMULATION (BM=BL) WITH MULTIPLE RECONNECTION-GENERATED FLUX ROPES CONFIRM A UBIQUITOUS PRESENCE OF TRIPOLAR BM ACROSS THE CS AND LARGELY INDEPENDENT OF THE THIRD DIRECTION. A 9.5-YEAR WIND SURVEY OF SOLAR WIND EXHAUSTS USING A 12-S RUNNING WINDOW SUGGESTS THAT TRIPOLAR BM PERTURBATIONS ARE PRESENT ACROSS ~20% OF 700 EXHAUSTS. THE WIND SURVEY SUGGESTS THAT EXHAUSTS WITH LARGER TRIPOLAR BM INCREASES RELATIVE TO THE BACKGROUND FIELD COINCIDE WITH DEEPER TRIPOLAR BM DIPS. OUR INITIAL 3D PIC SIMULATION REPRODUCES A SIMILAR BEHAVIOR. THE SCIENCE OBJECTIVE OF THE PROPOSED WORK IS TO EXPLAIN THE MECHANISM RESULTING IN A TRIPOLAR BM ACROSS SOLAR WIND EXHAUSTS AND THE NATURE OF THE CURRENTS THAT MUST SUPPORT THEM BY ANSWERING THE FOLLOWING SCIENCE QUESTIONS; Q1: WHAT IS THE OCCURRENCE FREQUENCY OF TRIPOLAR BM PERTURBATIONS ACROSS SOLAR WIND EXHAUSTS AT 1 AU? DO FREQUENCY AND BM PERTURBATION MAGNITUDES DEPEND ON CS ORIENTATION AND NORMAL WIDTH BM/BL RATIO OR ANY OTHER EXTERNAL PARAMETER? Q2: WHAT IS THE CHARACTERISTIC SCALE (ION OR ELECTRON) OF TRIPOLAR BM PERTURBATIONS ALONG SOLAR WIND EXHAUSTS AT 1 AU? Q3: WHAT DO PIC SIMULATIONS OF RECONNECTION REVEAL TO BE THE PHYSICAL MECHANISM(S) FOR THE FORMATION AND EVOLUTION OF TRIPOLAR BM PERTURBATIONS IN 2D AND 3D GEOMETRIES? HOW ARE THE ASSOCIATED ELECTRON CURRENTS MAINTAINED? OUR METHODOLOGY WILL EMPLOY A COMBINATION OF SOLAR WIND OBSERVATIONS OF MAGNETIC FIELD AND PLASMA MOMENTS ACROSS EXHAUSTS OF DIFFERENT NORMAL WIDTHS AND ORIENTATIONS AND NUMERICAL PIC SIMULATIONS OF RECONNECTION IN 2D AND 3D TO EXPLORE TRIPOLAR BM EVOLUTION IN DIFFERENT PARAMETER REGIMES GUIDED BY SOLAR WIND EXHAUST OBSERVATIONS. PI ERIKSSON WILL EMPLOY HIS EXHAUST DETECTION ALGORITHM WITH 12-S 18-S AND 4-MIN RUNNING WINDOWS THROUGH PUBLICALLY AVAILABLE WIND DATA TO ADDRESS Q1 AND ANALYZE EXHAUSTS WITH ~5-1000 DI NORMAL WIDTHS. HE WILL EXAMINE MULTI-SPACECRAFT CLUSTER AND MMS OBSERVATIONS ACROSS SOLAR WIND EXHAUSTS WITH TRIPOLAR BMS TO ADDRESS Q2 AND EXPLORE CS STRUCTURE USING THE MMS CURLOMETER TECHNIQUE. CO-I LAPENTA WILL RUN THE ELECTROMAGNETIC IPIC3D CODE IN 2D AND 3D. CO-I NEWMAN WILL ANALYZE IPIC3D RESULTS AND ADDRESS Q3 IN CLOSE COLLABORATION WITH THE TEAM. THE PROPOSED WORK TO UNDERSTAND THE RECONNECTION-RELATED TRIPOLAR BM AND SOLAR WIND CS STRUCTURE IS TIMELY SINCE IT DIRECTLY INFLUENCES THE PLANNING OF FUTURE OBSERVATIONS BY THE PARKER SOLAR PROBE AND SOLAR ORBITER MISSIONS. OUR SCIENCE OBJECTIVE TO EXPLORE SOLAR WIND STRUCTURE THROUGH MAGNETIC RECONNECTION AND OBTAIN A DEEPER UNDERSTANDING OF FLUX ROPE DYNAMICS ACROSS SOLAR WIND EXHAUSTS IS HIGHLY COMPELLING. IT DIRECTLY ADDRESSES THE 4TH HIGH-LEVEL SCIENCE GOAL TO "DISCOVER AND CHARACTERIZE FUNDAMENTAL PROCESSES THAT OCCUR BOTH WITHIN THE HELIOSPHERE AND THROUGHOUT THE UNIVERSE" AS STATED IN THE HELIOPHYSICS DECADAL SURVEY.