Validation of the use of THEMIS-B and THEMIS-C as a near-Earth solar wind monitor  

作　　者：DianJun Zhang WenLong Liu Zhao Zhang 

机构地区：[1]School of Space and Environment,Beihang University,Beijing 100191,China [2]Key Laboratory of Space Environment Monitoring and Information Processing,Ministry of Industry and Information Technology,Beijing 100191,China

出　　处：《Earth and Planetary Physics》2022年第6期546-554,共9页地球与行星物理（英文版）

基　　金：supported by the National Natural Science Foundation of China (grants 41821003 and 41974194)

摘　　要：Two THEMIS(Time History of Events and Macroscale Interactions during Substorms)spacecraft,B and C,began orbiting the Moon in 2011 and have since provided routine measurements of the plasma conditions in the lunar orbit.In this study,we systematically compare these measurements in near-Earth space with solar wind measurements obtained from the Lagrangian 1(L1)point and propagated to the Earth,including measurements in the OMNI database and from the Wind spacecraft.A statistical comparison between THEMIS data and data from the OMNI database from September 2011 to December 2017 showed that the Y and Z components of the magnetic field and the flow speed are generally consistent between the two data sets.The ion number density and the dynamic pressure measured by THEMIS in near-Earth space are lower than those in the OMNI database,suggesting possible variation in the solar wind environment while propagating from the L1 point to near-Earth space.We further show two examples in which near-Earth solar wind measurements are applied in calculating the magnetopause location and in quantifying the magnetic field response to interplanetary shocks.Both examples suggest that using solar wind data from near-Earth space achieves better results than using solar wind data from the L1 point.These results provide validation of THEMIS-B and THEMIS-C as an alternative monitor of the near-Earth solar wind environment.

关 键 词：interplanetary shocks solar wind MAGNETOSPHERE 

分 类 号：P353.8[天文地球—空间物理学]