Adding Lunar Observations to Multi-point Observations around Earth to Determine the Structure Heliospheric Discontinuities

The Chinese Chang'E 4 spacecraft landed on the Moon on January 3, 2019. The Lunar Lander Neutrons and Dosimetry (LND) instrument aboard the Chang'E 4 lander provides measurements of the radiation environment on the Moon. Some of its data products are provided at a cadence of once per minute. Combining such data with high time resolution data from other spacecraft near Earth (i.e., ACE, DSCOVR, SOHO, and Wind at L1) allows to determine the three-dimensional structure of discontinuities in the solar wind when (instrumental) counting statistics are good enough.

We will present first attempts at reconstructing the inclination angles of large-scale heliospheric discontinuities using data from ACE, Chang'E 4, DSCOVR, SOHO, and Wind. We assume a radially flowing solar wind speed of constant speed in individual solar wind streams and investigate the timing of discontinuities in count rates of particle and solar-wind instruments on these spacecraft.