A transformative advance in Earth science is the development of low-temperature thermochronometry to date Earth surface processes or quantify the thermal evolution of rocks through time. Grand challenges and new directions in low-temperature thermochronometry involve pushing the boundaries of these techniques to decipher thermal histories operative over seconds to hundreds of millions of years, in recent or deep geologic time and from the perspective of atoms to mountain belts. Here we highlight innovation in bedrock and detrital fission track, (U-Th)/He, and trapped charge thermochronometry, as well as thermal history modeling that enable fresh perspectives on Earth science problems. These developments connect low-temperature thermochronometry tools with new users across Earth science disciplines to enable transdisciplinary research. Method advances include radiation damage and crystal chemistry influences on fission track and (U-Th)/He systematics, atomistic calculations of He diffusion, measurement protocols and numerical modeling routines in trapped charge systematics, development of He-4/He-3 and new (U-Th)/He thermochronometers, and multimethod approaches. New applications leverage method developments and include quantifying landscape evolution at variable temporal scales, changes to Earth's surface in deep geologic time and connections to mantle processes, the spectrum of fault processes from paleoearthquakes to slow slip and fluid flow, and paleoclimate and past critical zone evolution. These research avenues have societal implications for modern climate change, groundwater flow paths, mineral resource and petroleum systems science, and earthquake hazards.
