Exogenic versus endogenic features of the planetary satellites

Abstract

Overview. A primary tool for studying icy bodies in the solar system is optical remote sensing. One focus of that research is inferring surface composition, since that may yield important clues about the formation and evolution of planetary satellites. In general, researchers can typically probe the very top layer of the surface (down to a mm or so) by these means. However, the uppermost part of a surface is typically exposed to solar UV, cosmic rays, and a local environment of plasma, energetic charged particles, and dust (cometary and other forms). Two processes that are important for this discussion are, additions to the surface (e.g., material from sources like Io's volcanoes that reach other bodies and solar wind ions) and weathering of the surface (e.g., physical and chemical changes as described in Johnson et al. 2004). Here, the latter includes all external driving such as sublimation and sputtering, and dust and cosmic ray impacts.

Pitch Angle Distribution of MeV Electrons in the Magnetosphere of Jupiter

“…Understanding how Jupiter accelerates and transports electrons in such an efficient manner despite many sink processes is important to develop a universal understanding of planetary radiation belts. Furthermore, the characterization and understanding of the Jovian energetic electrons are critical for the assessment of radiation risk for artificial satellites (e.g., Carlton et al., 2018; de Soria‐Santacruz et al., 2016; Garrett & Jun 2021; Sicard‐Piet et al., 2011), and for the study of moon surface weathering (Nordheim et al., 2018; Paranicas et al., 2021).…”