It worked!

Just before 6:30 pm ET, SpaceX -- run by Tesla (TSLA) CEO Elon Musk -- launched a used rocket. It marked the first time in the history of spaceflight that the same rocket has been used on two separate missions to orbit.

After successfully launching a satellite toward geosynchronous orbit -- 22,000 miles into space -- the rocket then returned to Earth and landed on a remotely piloted platform, known as a droneship, in the Atlantic Ocean. It was the company's sixth successful landing on a seaborne platform.

The SpaceX video showed the empty droneship, named Of Course I Still Love You, awaiting the return of the rocket, set against a deep blue ocean background. The video feed cut out momentarily and then came back on to show the rocket standing upright on the platform. The landing took place about eight minutes after launch.

Falcon 9 first stage has landed on Of Course I Still Love You — world's first reflight of an orbital class rocket. — SpaceX (@SpaceX) March 30, 2017

"It shows you can fly and refly an orbit-class booster, which is the most expensive part of the rocket," Musk said on a SpaceX webcast. "This is ultimately a huge revolution in spaceflight."

And shortly after the landmark success, Musk took to Twitter to announce his next goal for SpaceX: To launch a rocket twice in 24 hours.

Incredibly proud of the SpaceX team for achieving this milestone in space! Next goal is reflight within 24 hours. — Elon Musk (@elonmusk) March 30, 2017

The launch was a huge step for SpaceX. Reusing rockets is essential for companies like SpaceX that want to drive down the cost of space travel.

Related: SpaceX to fly two space tourists around the moon in 2018

SpaceX's Falcon 9 rocket costs about $62 million. Using it more than once can drastically bring down the price of a single launch.

The company confirmed to CNNMoney in August that its client for this trip received a discount on the Falcon 9 sticker price, but it declined to say by how much.

COO Gwynne Shotwell said in an interview that aired on SpaceX's webcast of the flight that reusable rockets are also a huge leap forward for SpaceX's plans to travel to Mars.

"Given the goals of SpaceX are to provide space transportation to other planets, we want to make sure whoever we take can come back," she said.

Obviously, she said, that requires developing rockets that can launch more than once.

SpaceX has been working toward its goal of using recycled rockets for more than a year. It's made 14 attempts to recover the first stage of its Falcon 9 rockets, and so far nine have been successful.

The rocket that SpaceX used during Thursday's mission was previously used in an April 2016 mission to the International Space Station. After launch, it was guided to a landing on the same droneship.

Related: SpaceX successfully tests Raptor engine it plans to send to Mars

That same droneship, named Of Course I Still Love You, also recaptured the first-stage rocket on Thursday.

But recapturing the rocket was a secondary concern for SpaceX. The primary goal was to deliver a communications satellite into geosynchronous orbit for the company that commissioned this launch, SES.

Successful deployment of SES-10 to geostationary transfer orbit confirmed. pic.twitter.com/FkVoUYSsmq — SpaceX (@SpaceX) March 30, 2017

The satellite -- called SES-10 -- is intended to provide improved TV, radio, telephone and internet coverage for South America. SES says SES-10 will also have "the ability to support off-shore oil and gas exploration."

SpaceX announced about 32 minutes after takeoff that the satellite had been successfully deployed.