Microgravity tends to produce rounder, cooler flames
This shows the difference between combustion in normal gravity (left) and microgravity (right). Unlike on Earth, hot, less dense air does not rise in microgravity.
As a result, other processes, like the diffusion of particles from a high temperature to a low temperature area, dominate.
Studying combustion in space reveals more about the fundamental physics of the phenomenon and could help develop fire-suppression technology for future space missions.