So how on Earth could Relativity Space compete with SpaceX?
Well, Relativity has something SpaceX doesn’t, a 3D printer that can make rockets! This might sound like a gimmick to some, but it is a truly revolutionary piece of technology in reality.

The printer is known as Stargate. It can print around 95% of a rocket, including fuel tanks, rocket engines and payload capsules in various metal alloys to an incredibly high level of accuracy.
This gives Relativity some crucial advantages over SpaceX. 3D printing is one of the fastest methods of production, Relativity claim they can build a functional rocket capable of commercial launches in just two months. This means they can do rapid prototyping and out develop their competitors. This is why their rocket engine, Aeon 1 has already had over 500 test fires, and is already a proven and refined engine, despite only being a few years old.

3D printing also means they can have some very unique architecture. This is most notable in the Aeon 1 engine, which only has a hundred parts, whereas other engines typically have well over a thousand parts. Things like cryogenic fuel lines are embedded into the combustion funnel walls rather than being welded onto them, as they are in other rocket engines. Not only does this mean assembly is quicker and easier, but it means the design can be optimised, far more than traditional engines, as there are fewer manufacturing limitations.
But, Relativity has also taken a note from SpaceX’s book. Their first launch vehicle, the Terran 1, has a reusable first stage that lands just like the Falcon 9. The first test launch is scheduled for early 2022, but we already know some details of what the commercial Terran 1 will be capable of, a cost per launch of $12 million for 1,250 kg to LEO.