Elon Musk's private spaceflight company SpaceX made history last night, successfully launching its Falcon 9 rocket into space and then landing the booster rocket that powered the flight so that it can be reused.
Musk called the landing "absolutely perfect," according to CBS, saying, "We could not have asked for a better mission."
Falcon 9 was carrying 11 satellites into orbit. But the most important part of the mission was landing the first stage — the part of the rocket that powers the first part of its flight, enough to travel about 50 miles into the atmosphere — at Cape Canaveral so that it could be used again.
Why a reusable rocket matters
Creating a reusable rocket has been a major goal for SpaceX, and one it's struggled with. Earlier attempts this year failed, and in June an uncrewed SpaceX rocket exploded in midair. This was the first flight since June's failure.
Jeff Bezos's private spaceflight company, Blue Origins, successfully landed a rocket in June, although it only went into suborbital space, not all the way into orbit. ("Welcome to the club," Bezos tweeted at Musk.)
SpaceX made a few changes to the rocket, including trying to land it on the ground rather than on a platform on the ocean, one of the things that made the earlier attempts so challenging.
Landing the rocket is revolutionary not just because it was a feat of impressive engineering, but because it could eventually make space travel cheaper. Most of the equipment used to put cargo or people in orbit is destroyed after each use. SpaceX Musk famously likened this to throwing away a brand new 747 after a single flight to London.
From the beginning, his company has sought to make spaceflight possible with reusable components. Building a new Falcon 9 rocket costs $54 million, but using it to put a payload into orbit costs only about $200,000 worth of fuel. Figuring out a way to reuse the rocket could make all sorts of missions — commercial satellite launches, collaborations with NASA, and space tourism — cheaper by orders of magnitude.