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We provide a post-mission assessment of the science and data from the Electric and Magnetic Field Instrument Suite and Integrated Science (EMFISIS) investigation on the NASA Van Allen Probes mission. An overview of important scientific results is presented, covering all of the key wave modes and DC magnetic fields measured by EMFISIS. Discussion of the data products, which are publicly available, follows to provide users with guidance on characteristics and known issues of the measurements. We present guidance on the correct use of derived products, in particular, the wave-normal analysis (WNA) which yields fundamental wave properties such as polarization, ellipticity, and Poynting flux. We also give information about the plasma density derived from measuring the upper hybrid line in the inner magnetosphere.

This paper presents the highlights of joint observations of the inner magnetosphere by the Arase spacecraft, the Van Allen Probes spacecraft, and ground-based experiments integrated into spacecraft programs. The concurrent operation of the two missions in 2017–2019 facilitated the separation of the spatial and temporal structures of dynamic phenomena occurring in the inner magnetosphere. Because the orbital inclination angle of Arase is larger than that of Van Allen Probes, Arase collected observations at higher $L$ L -shells up to $L \sim 10$ L ∼ 10 . After March 2017, similar variations in plasma and waves were detected by Van Allen Probes and Arase. We describe plasma wave observations at longitudinally separated locations in space and geomagnetically-conjugate locations in space and on the ground. The results of instrument intercalibrations between the two missions are also presented. Arase continued its normal operation after the scientific operation of Van Allen Probes completed in October 2019. The combined Van Allen Probes (2012-2019) and Arase (2017-present) observations will cover a full solar cycle. This will be the first comprehensive long-term observation of the inner magnetosphere and radiation belts.

Plumes have been identified as an access region for chorus waves to enter the plasmasphere. Here, for the first time, chorus wave properties are parameterized by distance from the plume boundary. Case studies and statistical analysis indicate that the polar wave vector angle

The ExoMars 2020 Surface Platform will conduct environmental and geophysical measurements with the aim of studying the Martian surface and subsurface environment at the landing location. The Surface Platform instrumentation will include the Wave Analyzer Module (WAM) as a European contribution to the Russian–led Martian ground electromagnetic tool (MAIGRET) instrument. The wave analyzer module will be dedicated to measurements of magnetic field fluctuations in the frequency band from 100 Hz to 20 kHz. The scientific questions which we plan to address by measurements of the WAM have never been answered by direct measurements of the fluctuating magnetic fields in the appropriate range of frequencies directly on the surface of the planet. The immediate questions related to these targets are: 1. Can we observe electromagnetic radiation from electric discharges in the Martian dust storms? 2. Can we observe electromagnetic radiation propagating from the interplanetary space down to the surface of the planet?

We study the penetration of lightning induced whistler waves through the ionosphere by investigating the correspondence between the whistlers observed on the DEMETER and MAGION-5 satellites and the lightning discharges detected by the European lightning detection network EUCLID. We compute all the possible differences between the times when the whistlers were observed on the satellite and times when the lightning discharges were detected. We show that the occurrence histogram for these time differences exhibits a distinct peak for a particular characteristic time, corresponding to the sum of the propagation time and a possible small time shift between the absolute time assigned to the wave record and the clock of the lightning detection network. Knowing this characteristic time, we can search in the EUCLID database for locations, currents, and polarities of causative lightning discharges corresponding to the individual whistlers. We demonstrate that the area in the ionosphere through which the electromagnetic energy induced by a lightning discharge enters into the magnetosphere as whistler mode waves is up to several thousands of kilometres wide.

Solar Orbiter is an M-class mission in the ESA Science Programme Cosmic Vision 2015 – 2025 having an orbit with perihelion as low as 0.28 AU. The Radio Plasma Waves (RPW) Analyzer on board will provide new insights into the microscale phenomenon, the propagation modes of the radio waves and the localization of their source regions. The three electric antennas (each 5 meters long) are designed to be mounted on booms in a perpendicular plane to the spacecraft-Sun axis. Effective antenna lengths and directions are different from the physical ones due to their coupling with the spacecraft body. These parameters have been investigated considering various antenna placements on the spacecraft body [Rucker et al., this issue]. Results indicate that all effective antenna directions will be slightly tilted towards the Sun. This paper discusses a possible accuracy of the Direction Finding (DF) with respect to this tilt angle and uncertainties of the effective antenna parameters.

We report a study of penetration of the VLF electromagnetic waves induced by lightning to the ionosphere. We compare the fractional hop whistlers recorded by the ICE experiment onboard the DEMETER satellite with lightning detected by the EUCLID detection network. To identify the fractional hop whistlers, we have developed software for automatic detection of the fractional-hop whistlers in the VLF spectrograms. This software provides the detection times of the fractional hop whistlers and the average amplitudes of these whistlers. Matching the lightning and whistler data, we find the pairs of causative lightning and corresponding whistler. Processing data from ~200 DEMETER passes over the European region we obtain a map of mean amplitudes of whistler electric field as a function of latitudinal and longitudinal difference between the location of the causative lightning and satellite magnetic footprint. We find that mean whistler amplitude monotonically decreases with horizontal distance up to ~1000 km from the lightning source. At larger distances, the mean whistler amplitude usually merges into the background noise and the whistlers become undetectable. The maximum of whistler intensities is shifted from the satellite magnetic footprint ~1° owing to the oblique propagation. The average amplitude of whistlers increases with the lightning current. At nighttime (late evening), the average amplitude of whistlers is about three times higher than during the daytime (late morning) for the same lightning current.