SpaceX launches first recycled rocket in historic leap
SpaceX has launched its first recycled rocket, 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 Centre, hoisting a broadcasting satellite into a clear early evening sky.
It was the first time SpaceX founder Elon Musk had tried to fly a booster that had flown 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 after lift-off, just off the east Florida coast.
Mr Musk called it an "incredible milestone in the history of space", adding: "This is going to be a huge revolution in spaceflight."
The first stage landed on an ocean platform almost exactly a year ago after a space station launch for Nasa.
SpaceX refurbished and tested the 15ft booster, still sporting its nine original engines. It nailed another vertical landing at sea on Thursday once it had finished boosting the satellite for the SES company, from Luxembourg.
Long-time customer SES got a discount for agreeing to use a salvaged rocket, but would not say how much. It was not just about the savings, said chief technology officer Martin Halliwell.
He 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, Mr Halliwell said, providing confidence that everything would go well.
SES is considering more launches later this year on reused Falcon boosters.
"Someone has to go first," Mr Halliwell said at a news conference earlier in the week.
Boosters are typically discarded after lift-off, sinking into the Atlantic.
SpaceX began flying back the Falcon's first-stage, kerosene-fuelled boosters in 2015, and has landed eight - three at Cape Canaveral and five on ocean platforms.
The company is working on a plan to recycle more Falcon parts, like the satellite enclosure. For now, the second stage used to get the satellite into the high orbit is abandoned.
The first stage is the most expensive part of the rocket, according to Mr Musk.
Blue Origin, an aerospace company started by another tech billionaire, Jeff Bezos, has already reflown a rocket. One of his New Shepard rockets has soared five times from Texas, but the flights were suborbital.
Nasa has also shared the quest for rocket reusability. During the space shuttle programme, 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, Mr Halliwell said engineers went through it with a fine-tooth comb after its lift-off in April last year.
He was not so sure 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 is 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. Mr Musk's ultimate goal is to establish a human settlement on Mars.