SpaceX successfully launched and then retrieved its first recycled rocket Thursday, the biggest leap yet in its bid to drive down costs and speed up flights.

The Falcon 9 blasted off from Florida's Kennedy Space Center, hoisting a broadcasting satellite into the clear early evening sky on the historic rocket reflight.

It was the first time SpaceX founder Elon Musk tried to fly a booster that soared before on an orbital mission. He was at a loss for words after the booster landed on the bull's-eye of the ocean platform following liftoff, just off the east Florida coast.

Musk called it an "incredible milestone in the history of space" after the booster touchdown.

He added: "This is going to be a huge revolution in spaceflight."

This particular first stage landed on an ocean platform almost exactly a year ago after a space station launch for NASA. SpaceX refurbished and tested the 15-foot booster, still sporting its nine original engines. It nailed another vertical landing at sea Thursday once it was finished boosting the satellite for the SES company of Luxembourg. SpaceX employees jammed outside Mission Control at the Hawthorne, California, company headquarters cheered loudly every step of the way — and again when the satellite reached its proper orbit.

Longtime customer SES got a discount for agreeing to use a salvaged rocket, but wouldn't say how much. It's not just about the savings, said chief technology officer Martin Halliwell.

Halliwell called it "a big step for everybody — something that's never, ever been done before."

SpaceX granted SES insight into the entire process of getting the booster ready to fly again, Halliwell said, providing confidence everything would go well. SES, in fact, is considering more launches later this year on reused Falcon boosters.

"Someone has to go first," Halliwell said at a news conference earlier in the week.

Boosters — the most expensive part of the rocket, according to Musk — typically are discarded following liftoff, sinking into the Atlantic. SpaceX began flying back the Falcon's first-stage, kerosene-fueled boosters in 2015; it's since landed eight boosters, three at Cape Canaveral and five on ocean platforms — actually, six times at sea counting Thursday's redo. The company is working on a plan to recycle even more Falcon parts, like the satellite enclosure. For now, the second stage used to get the satellite into the proper, high orbit is abandoned.

Blue Origin, an aerospace company started by another tech billionaire, Jeff Bezos, already has reflown a rocket. One of his New Shepard rockets, in fact, has soared five times from Texas. These flights, however, were suborbital; in other words, nothing went into orbit.

NASA also has shared the quest for rocket reusability. During the space shuttle program, the twin booster rockets dropped away two minutes into flight and parachuted into the Atlantic for recovery. The booster segments were mixed and matched for each flight.

As for this SpaceX reused booster, Halliwell said engineers went through it with a fine-toothed comb following its liftoff in April 2016. He wasn't so sure, though, about the cleaning job.

"It's a bit sooty," he said with a smile.

SES has a long history with SpaceX. A SES satellite was on board for SpaceX's first commercial launch in 2013.

SpaceX — which aims to launch up to six reused boosters this year — is familiar with uncharted territory.

Besides becoming the first commercial cargo hauler to the International Space Station, SpaceX is building a capsule to launch NASA astronauts as soon as next year. It's also working to fly two paying customers to the moon next year, and is developing the Red Dragon, a robotic spacecraft intended to launch to Mars in 2020 and land. Musk's ultimate goal is to establish a human settlement on Mars.

Key to all of this, according to Musk, is the rapid, repeating turnaround of rockets — and employees. SpaceX posted a help wanted ad on its webcast following the launch.