SpaceX fires up Starship SN4 prototype yet again (video) - Space.com

But don't expect the craft to take flight until SpaceX's Demo-2 mission to the space station has launched.

Elon Musk's company is gearing up to launch its first-ever crewed mission on Saturday (May 30), a crucial test flight called Demo-2 that will send two NASA astronauts to the International Space Station.

Demo-2 employs SpaceX's Crew Dragon capsule and Falcon 9 rocket, and the flight will lift off from NASA's Kennedy Space Center in Florida.

Related: SpaceX's Starship and Super Heavy rocket in pictures.

SpaceX briefly fired up the single Raptor engine of Starship SN4, the latest prototype of the company's Mars-colonizing spaceship.

It will launch off Earth atop a huge rocket called Super Heavy, which will sport 31 Raptors of its own.

(Starship won't need Super Heavy to lift off from the moon or Mars, which have much weaker gravitational pulls than our planet does.)!

Both Starship and Super Heavy will be fully and rapidly reusable, making the system affordable enough to enable all sorts of ambitious exploration projects, Musk has said.

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