It might seem odd for an idea as fantastic as colonizing Mars to come up during something as routine as the launch of a telecom satellite, but with Elon Musk’s SpaceX, the red planet orbits over everything.

That was the case on Thursday, when SpaceX successfully launched and landed a previously flown Falcon 9 first-stage booster, a milestone in the company’s quest to make access to space more affordable and sustainable en route to developing a future colony of humans on Mars this century.

The landing on the company’s autonomous droneship, Of Course I Still Love You, essentially demonstrates that it is indeed possible to reuse first stage boosters for multiple flights. Reusing this architecture essentially saved SpaceX about 80 percent of the costs of the launch, a massive savings if applied to more launches downstream in the company’s future operations. All SpaceX rockers, beyond the relatively small Falcon 9, up to to the so-called “BFR” that will launch colonizer vessels to parking orbit, are designed for reuse.

“Full and rapid reusability is our mantra,” firmware engineer Tom Praderio said Thursday during SpaceX’s webcast of the mission.

Although the world’s first reflight for a flight-proven rocket is now behind it, SpaceX’s work is far from over. “The goal of SpaceX is to provide transportation to allow people to move to other planets,” said company president Gwynne Shotwell before the attempt. “We’re not one-way-trip to Mars people. We want people to be able to come back.”

“From that perspective,” she said, “you need to have a reusable system,” similar to modern-day commercial aircraft. The ultimate goal is to develop and demonstrate architecture which could be capable of 10 or more reflights — and be flown, landed, and flown again on the very same day (Musk tweeted something similar).

SpaceX headquarters mars
Flickr user Steve Jurvetson posted this photo in 2010 with the caption, "Seen at SpaceX headquarters this afternoon: a huge image of Mars adorns the wall to Elon and Gwynne’s offices. Keeping an eye on the prize."

Employees at SpaceX headquarters in Hawthorne, California are reminded of Mars daily, with wall-sized photos reminding them of the company’s mission: Get there.

Kate Tice, a certification engineer at SpaceX, explained during the webcast that reusability is fundamental to establishing not just outposts, but “sustaining cities on other planets” like Mars. One Falcon 9 rocket currently costs about $62 million, while fuel costs for each launch are just $200,000 to $300,000, about 0.4 percent the cost of the launch. Recovering and reusing the rocket multiple times significantly reduces the costs. SpaceX wants to get the cost of a single flight to Mars for dozens of people down to around $100,000 which is “key to establishing a city on Mars,” she said.

Reusing a rocket is just the first step towards that goal — but it’s a big one. “This will be written up,” said Shotwell. “This is a historic event.”

The one person who didn’t mention Mars was the person perhaps most obsessed with it at SpaceX. During his brief post-landing comments — which he delivered from the control room at Kennedy Space Center — seemed moved by the moment, at one point admitting he was at a loss for words.

“You can fly, and re-fly an orbit-class booster,” Musk said. “This is ultimately going to be a huge revolution in spaceflight.”

Photos via Steve Jurvetson, SpaceX