Starship Raptor Engines: How SpaceX's Methalox Powerplant Is Changing Spaceflight

When you think about what makes SpaceX’s Starship different from every other rocket ever built, the answer starts with the Raptor engine, a full-flow staged combustion engine that burns liquid methane and liquid oxygen to produce extreme thrust with high reusability. Also known as a methalox engine, it’s the first of its kind to power a fully reusable orbital vehicle—and it’s the reason Starship can land, refuel, and fly again without needing a complete rebuild. Unlike older rockets that used kerosene or hydrogen, Raptor engines are designed to be refueled on Mars using locally made fuel, making them essential for long-term space exploration.

What makes Raptor engines so special isn’t just their power—it’s how they’re built to last. Each engine runs at pressures higher than any previous rocket engine, with combustion chambers that cycle through thousands of firing cycles. That’s why they’re paired with methalox engines, a propulsion system using liquid methane and liquid oxygen as propellants. Methane burns cleaner than kerosene, leaves less soot, and is easier to produce on Mars from CO2 and water ice. Oxygen, of course, is critical for combustion, and both fuels are stored cryogenically, which ties directly into the need for cryogenic propellant depots, orbital fuel stations that store liquid methane and oxygen for in-space refueling. These depots are the next step: Starship won’t just fly to Mars—it’ll refuel in orbit first, carrying more payload than any rocket in history.

It’s not just about going farther. Raptor engines are the backbone of SpaceX’s entire business model: rapid reuse, low cost, and high flight rate. Every time a Starship lands and is inspected for the next launch, it’s the Raptor engines that take the most stress—and the most attention. Engineers monitor combustion stability, nozzle erosion, and fuel line integrity after every flight. That’s why posts on this page dive into everything from how these engines are tested on the ground to how they compare to other methalox systems like Blue Origin’s BE-4. You’ll also find breakdowns of why methane beats kerosene for Mars, how the engine’s turbopumps work under extreme conditions, and what happens when you try to restart a Raptor engine in space after a long coast.

There’s no other engine like it in active service. No other company has built, flown, and reused a full-flow staged combustion engine at this scale. The Raptor isn’t just an upgrade—it’s a reset. And as SpaceX ramps up Starship flights, these engines are becoming the standard for the next era of spaceflight. Below, you’ll find real-world analysis of how they’re tested, how they’re maintained, and why they’re the only viable path to making life multiplanetary.