Watch Elon Musk react incredulously to SpaceX’s recycled rocket landing: “I’m at a loss for words”

SpaceX made aerospace history this evening when it successfully launched one of its used Falcon 9 rockets back into space and landed it again. While rocket boosters are typically discarded at sea, the launch marked the first time an orbital rocket safely returned from space for a second time, a watershed moment for CEO Elon Musk’s vision of more affordable spaceflight. 

Here’s an excerpt from the full live stream—see the breathtaking ending at 9:42, and Musk’s comments soon after that:

Shortly after the rocket delivered a communications satellite to orbit and then piloted itself back to a drone ship in the Atlantic for a second at-sea landing, Musk said the “incredible milestone” followed 15 years of work “and a lot of difficult steps along the way.” Among the challenges that remain: satisfying serious safety concerns for the astronauts who are expected to ride these and Boeing’s new rockets within the coming years. A recent GAO report indicates astronauts won’t ride them to space until 2019

For the moment, SpaceX and the space industry have cause to celebrate. “You can fly and re-fly an orbit class booster, which is the most expensive part of the rocket,” said Musk, his voice quivering, his comments peppered with a few “incredibles.” “This is going to be a huge revolution in spaceflight. Its’s like if you had airplanes you threw away after every flight versus, you could reuse them multiple times. […] And um, yeah. I’m sort of at a loss for words.”