Methane, while less dense (thus requiring bigger tanks) has a higher specific energy than kerosene, and thus has a higher ISP (rocket efficiency). Methane is al

Methane, while less dense (thus requiring bigger tanks) has a higher specific energy than kerosene, and thus has a higher ISP (rocket efficiency). Methane is also less sooty and should have better cooling as its a "mild cryogenic" like liquid oxygen. Basically, it's between LH2 (hydrogen: high ISP, very low density, very very cold) and RP-1 (kerosene: lower ISP, high density, room temp) and may be a good compromise. And its derivable on Mars. Downside is there's very little flight heritage for a methane engine, so most of this is theoretical. EDIT: Paper: http://thehuwaldtfamily.org/jtrl/research/Propulsion/Rocket%20Propulsion/Propellants/DLR,%20Comparative%20Study%20of%20Kerosene%20and%20Methane%20Engines.pdf http://thehuwaldtfamily.org/jtrl/research/Propulsion/Rocket%...