Determining the reliability of solar wind data propagated to Earth

Accurate ballistic propagation of solar wind observations measured at L₁ to the bow shock is crucial for our ability to predict and model space weather events. Global simulations used to predict interactions between the solar wind and Earth’s magnetosphere such as SWMF and LFM codes rely on solar wind parameters as input. Errors in the input will produce erroneous output. In this study, statistical correlations of ballistically propagated solar wind profiles from L₁ spacecraft and observations from ARTEMIS at lunar distances and THEMIS spacecraft just outside the bow shock are compared for one-hour intervals during periods when the near-Earth spacecraft were close to the Earth-Sun line. This study will identify what fractions of time the propagated L₁ solar wind observations and solar wind observed closer to Earth correlate at various values. Such correlation coefficient distribution functions may allow for the development of probability maps based on spacecraft location to improve predictions and model input.