A SpaceX Falcon 9 rocket recovered at sea from its maiden flight last year blasted off again from Florida on Thursday in the first successful launch of a recycled orbital-class booster, then capped the feat with another return landing on an ocean platform.

The unprecedented twin achievements of re-launching a used rocket and salvaging the vehicle yet again were hailed by billionaire SpaceX founder Elon Musk as a revolutionary step in his quest to slash launch costs and shorten intervals between space shots.

“This is a huge day,” Musk told reporters after the launch. “My mind's blown.” It took Space Exploration Technologies Corp, as the California-based company is formally known, 15 years to demonstrate that a rocket typically discarded in the ocean after a single flight could be recovered and reused.

The SpaceX chief executive said his next goal is to turn the booster around for relaunch in 24 hours, a milestone he said could be accomplished before the end of the year.

The potential is there for an over 100-fold reduction in the cost of access to space. If we can achieve that, it means humanity can become a space-faring civilization and be out there among the stars. This is what we want for the future, he said.

The Falcon 9 booster, which previously flew in April 2016, lifted off from the Kennedy Space Center at 2227 GMT to put a communications satellite into orbit for Luxembourg-based SES SA.

The boosters main section then separated from the rest of the rocket and flew itself back to a landing pad in the Atlantic, where it successfully touched down for its second at-sea return.

“We made a little bit of history today ... opened the door into a whole new era of spaceflight, said Martin Halliwell the chief technology officer for SES, who joined Musk at the news conference.

SpaceX landed an orbital rocket after launch for the first time in December 2015, a feat it has now repeated eight times. The Falcon 9 booster launched for the company's 33rd mission on Thursday was also the first to make a successful return landing in the ocean.

By reusing rockets, SpaceX aims to eventually cut its costs by about 30 percent, the company has said. It lists the cost of a Falcon 9 ride at $62 million but has not yet announced a price for flying on a recycled rocket. Not all the savings will be passed on to SpaceX customers, some of whom were awaiting the outcome of Thursdays flight before agreeing to fly on a used booster, Musk said.

The company spent at least $1 billion developing the technology to land and re-fly its rockets and aims to recoup its investment in the next year or so, Musk said.

The boosters are expected to be able to fly 10 times with no refurbishment and about 100 times with moderate reconditioning, though the one launched Thursday will be donated to the Cape Canaveral Spaceport for display, Musk said.

Proving the concept works is crucial to SpaceX, which is moving on from an accident in September that damaged another Florida site.

SpaceX also is working on a passenger spaceship, with two unidentified tourists signed up for a future trip around the moon. The company's long-term goal under Musk is to establish a colony on Mars and ferry people and cargo back and forth between the planets.

On Thursday, the rocket's second-stage, which is not recovered, continued firing to carry SES-10 into an initial egg-shaped orbit high above Earth, which it will provide television and other communications services to Latin America.