# Predicting the Structure of the Solar Corona and Inner Heliosphere during Parker Solar Probe's First Perihelion Pass

## TL;DR

This paper presents a 3D MHD model predicting the solar corona and heliosphere structure during Parker Solar Probe's first perihelion, aiding in data interpretation and understanding solar wind origins.

## Contribution

The study introduces a wave-turbulence-driven MHD model driven by solar magnetic field observations to predict solar corona and heliosphere structures during Parker Solar Probe's first perihelion.

## Key findings

- Parker was in wind from a positive-polarity equatorial coronal hole before encounter.
- During encounter, Parker connected to a negative-polarity equatorial coronal hole.
- Post-encounter, Parker linked to a positive-polarity northern polar coronal hole.

## Abstract

NASA's Parker Solar Probe (Parker) spacecraft reached its first perihelion of 35.7 solar radii on November 5th, 2018. To aid in mission planning, and in anticipation of the unprecedented measurements to be returned, in late October, we developed a three-dimensional magnetohydrodynamic (MHD) solution for the solar corona and inner heliosphere, driven by the then available observations of the Sun's photospheric magnetic field. Our model incorporates a wave-turbulence-driven (WTD) model to heat the corona. Here, we present our predictions for the structure of the solar corona and the likely {\it in situ} measurements that Parker will be returning over the next few months. We infer that, in the days prior to 1st Encounter, Parker was immersed in wind emanating from a positive-polarity equatorial coronal hole. During the encounter, however, field lines from the spacecraft mapped to another, negative-polarity equatorial coronal hole. Following the encounter, Parker was magnetically connected to the large, positive-polarity northern polar coronal hole. When the Parker data become available, these model results can be used to assist in their calibration and interpretation, and, additionally, provide a global context for interpreting the localized {\it in situ} measurements. In particular, we can identify what types of solar wind Parker encountered, what the underlying magnetic structure was, and how complexities in the orbital trajectory can be interpreted within a global, inertial frame. Ultimately, the measurements returned by Parker can be used to constrain current theories for heating the solar corona and accelerating the solar wind.