An Introduction to Mars Terraforming, 2025 Workshop Summary

Terraforming Mars is an age old science fiction concept now worth revisiting through the lens of modern science and technology. This document serves as a summary of contemporary ideas about Mars terraforming, prepared for attendees of the 2025 Green Mars Workshop. It presents one illustrative story of how Mars might be transformed into a habitable world. The story is told in reverse, beginning with possible planetary endpoints and tracing backward to the steps required to reach them. Along the way, it highlights alternative approaches, critical unknowns and research priorities, and the near term applications and benefits of terraforming research for planetary science, climate engineering, and sustainable technologies on Earth.