Fibre-optic sensing has rapidly evolved from a niche technology into a versatile observational tool capable of operating in environments that are challenging or inaccessible for conventional instruments. Its high sensitivity to measurements (eg: strain, temperature, pressure) and logistical advantages led to its increasing usage beyond standard terrestrial settings, opening new scientific frontiers.

This session focuses on the opportunities and challenges of applying fibre-optic sensing in extreme and unconventional environments, including the ocean and volcanic settings, deep boreholes, controlled temperature and pressure laboratory experiments, chemically reactive conditions and extraterrestrial or planetary exploration contexts. We invite contributions that explore novel deployments, experimental designs, and methodological advances enabling fibre-optic measurements where traditional sensors are impractical, as well as innovations that push fibre sensing technology into previously unattainable extreme settings.

By bringing together numerical simulations, laboratory and analogue experiments and field deployments, this session aims to highlight recent breakthroughs, discuss remaining challenges, and identify future directions for fibre-optic sensing, from controlled laboratory experiments to the deepest oceans and beyond Earth.