The Heliophysics and Planetary Science Branch studies the coupled Sun-Earth system and the terrestrial planets and icy satellites of our solar system. Our heliophysics portfolio includes instrumentation development, sounding rocket flight, and research focusing on energy transfer across physical scales throughout the solar atmosphere.  Our planetary science portfolio includes research on the origin, composition, and evolution of terrestrial planetary bodies, focusing on geological, geophysical, and related models, experiments, and observations conducted in the field, laboratory, and via analysis of remotely sensed data from space-based missions.