What is Cold gas?

Cold gas refers to gases that are at low temperatures, typically close to absolute zero, where molecular activity is minimal. In astrophysics, it often describes gas found in space that has not yet been heated by stars or other cosmic phenomena. Cold gas is significant in the study of star formation, as it can collapse under gravity to form new stars. Additionally, in the context of propulsion, "cold gas" can refer to the use of inert gases at low temperatures for thrust in certain types of spacecraft.