Interplanetary energetic electrons observed in Earth's polar cusp/cap/lobes

The Earth's polar cusp, cap and lobes are the important boundaries to transport the plasma and energy from the interplanetary medium to terrestrial magnetosphere. Interplanetary energetic electrons, mainly consisting of continuous solar wind superhalo electrons and transient solar energetic electron events both with typical power-law energy spectra, can provide a source of energetic electrons to the Earth's magnetosphere. After briefly summarizing recent results of solar wind superhalo electrons and solar energetic electron events, this paper reviews the first evidences for the direct and continuous entry of energetic electrons from the interplanetary medium to the Earth's polar cusp, cap and/or lobes, observed by one Chinese BeiDou navigation satellite. Such entering electrons can make a possible contribution to the generation of magnetospheric energetic electrons.