The catch that is essential to the company's decade-long effort to develop a fully reusable rocket.
The 52 metre Starship fell out of thick clouds over SpaceX's Starbase launch site, reignited engines to flip itself vertical and slowly descended into the tower's "Mechazilla" arms, engines still roaring.
Charred from the blazing heat of its return from space, the ship shut down its engines and hung still after the rocket system's longest mission yet.
"That was the missing link, the holy grail of spaceflight," SpaceX mission commentator Dan Huot said of the ship catch.
The towering two-stage rocket's Super Heavy booster - the rocket's bottom half - carried Starship to space on Friday, lifting off from SpaceX's Starbase, Texas, facilities.
That booster had failed to make a similar return to the launch pad some 10 minutes after liftoff, nixing SpaceX's plan to recover both parts of the rocket for the first time.
But the Starship upper stage's successful return after orbiting Earth 14 times for 22.5 hours marked a key engineering milestone in the whirlwind, multibillion-dollar development of Starship, which Elon Musk sees as the future workhorse for SpaceX's lucrative Starlink satellite business, as well as ambitions to put data centres in orbit, return humans to the moon and, eventually, settle on Mars.
After deploying 26 Starlink satellites in orbit Friday night while cruising some 260km in altitude, Starship on Saturday fired one of its engines to begin an atmospheric plunge while flying eastward over the Pacific Ocean.
It faced blistering heat as its orbital speed of some 17,000 miles per hour slowed to a supersonic free-fall in the skies above SpaceX's Starbase facilities on the Gulf Coast of south Texas.
With its aerodynamic fins folded back, two small fittings near the top of Starship hooked onto the launch tower's mechanical arms that had closed in to grasp it, allowing the vessel to hang a few hundred feet off the ground.
Musk and SpaceX engineers began inspecting the ship within hours of its catch.
"Ship 42 looks great!" Musk wrote on X, posting photos and videos from the launch tower.
SpaceX's dominance in the global launch industry is centred on its workhorse Falcon 9 rocket, which has launched over 700 times since 2010. That rocket's first stage is reusable, but its second stage - the part that delivers payloads into orbit - is discarded into the ocean after each flight.
With Starship, Musk wants a rocket system that can fly to space and back in a manner and tempo akin to commercial airplanes, with minimal refurbishment between flights.
Though Saturday's Starship recovery is a key milestone in that effort, SpaceX has yet to recover both Starship stages in a single mission, which would mark the first-ever return of an orbital launch system.
And Starship's heat shield, composed of hundreds of black hexagonal tiles that protect it from the blazing heat of atmospheric re-entry, is itself not yet fully reusable.
NASA's Space Shuttle system that ferried astronauts to the International Space Station before its 2011 retirement was partially reusable; its external fuel tanks that got it off Earth were discarded after each flight. The reusable spacecraft itself had to go through extensive refurbishment before re-flying.
SpaceX has spent more than $US15 billion ($A22 billion) on Starship's development.
NASA has provided $US3.2 billion ($A4.7 billion) as part of a contract valued at more than $US4 billion ($A5.9 billion) that SpaceX won in 2021 to return humans to the moon using Starship under the space agency's Artemis program.
NASA expects Starship, along with another moon lander under development by Jeff Bezos' Blue Origin, to start crewed flights to the moon in 2028, though several challenging development milestones remain with both mooncraft.
