Flight six of Starship was seen as a test of whether SpaceX's first booster catch was pure precision or relied on a stroke of luck after Musk - perhaps inadvertently - disclosed how close the last flight came to disaster.

In a clip posted to X showcasing his gaming chops in "Diablo IV," sharp-eared fans caught an employee briefing him that the Super Heavy booster was "one second away" from a system failure that could have spelled catastrophe.

The flight also carried Starship's first ever payload - a stuffed banana - and served as a swan song for the current generation of Starship prototypes.

Starship's upper stage meanwhile made a partial orbit of Earth, re-entered the atmosphere and splashed down in the Indian Ocean around an hour and five minutes after launch.

SpaceX employees erupted in cheers during a live feed watched by nearly nine million viewers, as the upper stage executed a near-vertical daylight splashdown off Australia's northwest coast, sending up a towering plume of water vapour before tipping over.

Key milestones included reigniting Starship's Raptor engines for the first time in space and trialing new heat shield materials.

With twice the thrust of the Saturn V rockets that powered Apollo missions, Starship is the most powerful rocket ever built.

Musk has already teased that its successor, Starship V3, will be "3X more powerful" and could take flight in about a year.

The flight comes as Musk is riding high on Trump's November 5 White House win, having campaigned extensively for the returning Republican leader, as well as donating staggering sums from his own fortune to the cause.

His loyalty has paid off. Musk has been tapped to co-lead a new "Department of Government Efficiency" - or DOGE, a cheeky nod to the meme-based cryptocurrency Musk loves to promote.

That in turn has led to concerns Musk could engage in "self-dealing" as the CEO is poised to straddle the line between government insider and corporate titan.