Comparing solar wind data collected by MESSENGER spacecraft to simulation data by AWSoM model

One of MESSENGER's primary science goals was to study the space environment of Mercury. Earlier MESSENGER studies have provided conclusive evidence that space plasma phenomena occurring within Mercury's structurally complex and highly dynamic magnetosphere are strongly driven by the solar wind. However, since MESSENGER is a single spacecraft mission, we have no knowledge of the upstream solar wind conditions when the MESSENGER spacecraft is inside Mercury's magnetosphere. As such, using predictions of solar wind parameters from a numerical solar wind model is essential in enhancing our understanding of the plasma processes that the spacecraft observes when inside Mercury's magnetosphere. In this project, our goal is to compare the solar wind data collected by the MESSENGER spacecraft with simulated outputs from a physics-based solar wind model called the Alfvén Wave Solar Atmosphere Model (AWSoM) developed at the University of Michigan. We are able to identify intervals of MESSENGER's data when the spacecraft is upstream of the bow shock and in the solar wind. It is then compared to twelve ADAPT realizations, of which two were chosen from the AWSoM model to compare the MESSENGER's data for CR2123 in 2012. The best data and model realization agreement was determined visually and by minimizing the mean square error. We also performed the Dynamic Time Warping technique to obtain better and more accurate comparison results between the data and model. To further these observations, solar wind data from the MESSENGER and AWSoM model could be compared to the other 11 Carrington rotations over 2012 to decide which Carrington rotation is best suitable for the data comparison. Our analysis of the Gong, Adapt-Gong, and MESSENGER's solar wind data indicates a strong agreement between MESSENGER's IMF measurements and AWSoM magnetic field output. The validation of the AWSoM model at Mercury over further years can benefit the upcoming Bepi-Colombo mission by providing more accurate solar wind predictions, especially during six Mercury flybys between now and orbit insertion in late 2025.