BOCA CHICA, Texas (KVEO) — Starship SN15, the latest version of Elon Musk’s planned Mars rocket, could take flight this week.

Musk tweeted on Monday that SN15 completed its static fire test, and is being prepared to take flight “later this week”. Records show the flight is tentatively scheduled for Wednesday, with Thursday as an alternate day.

SN15 will be the fifth high-altitude flight test of a Starship at Boca Chica in South Texas.

The purpose of the Starship high-altitude tests is to eventually use the Super Heavy Rocket as a “fully reusable transportation system designed to carry both crew and cargo to Earth orbit, the Moon, Mars and beyond,” according to SpaceX’s website.

Over the past five months, Space X has done four Starship high-altitude tests with prototypes SN11, SN10, SN9, and SN8.

The first was SN8 in December of last year, and the most recent SN11 in March.

Space X has been grooming SN15. According to Musk, the outcome of SN15 will have a different outcome.

SN15 is a much-improved Starship prototype, featuring “hundreds of design improvements across structures, avionics/software & engine,” Musk said via Twitter.

Two weeks ago, Musk tweeted that SpaceX was aiming to launch SN15 last week, but he has changed the time frame since.

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