Geothermal heat is an important source of energy on planets and moons. Geophysically, geothermal heat drives interior evolution, including processes like mantle convection and volcanism. Geothermal energy is a source of locally acyclic energy on Earth with perpetual sustainability, but planetary geotherms are a poorly studied source of planet-scale potential in settlements on the Moon and Mars. Finally, geothermal heat may offer a subsurface source of energy for planetary microbial communities that spans geologic eons, decoupled from dependence on seasonal insolation and stress from surface radiation. Planetary crustal geothermal environments (possibly tidal, in ocean worlds like Europa; radiogenic in bulk silicate bodies like Mars) thus become crucial for geophysical, exploration, and habitability questions of the Solar System and exoplanets. Accordingly, with the broad connectivity in science across ISRU energy needs, habitability, and planetary interior evolution, we encourage submissions on the significance and models of geothermal environments.

• EP - Earth and Planetary Surface Processes
• NS - Near Surface Geophysics