Mueller was willing to try a new path.
"[W]hen I met Elon, the rocket engine was key front-line technology for SpaceX," Mueller told LMU Magazine. "In addition, Elon's business plan and the way he wanted to set up the company really appealed to me. And he had the capital to do it. So when Elon said (to me and another prospective employee), if you guys join, we'll start the company, I signed on as one of the three co-founders." They started the company with the third co-founder, Chris Thompson, in May 2002.
Moving to start-up SpaceX was a big change for Mueller. "TRW is a huge company with a tiny propulsion department," Mueller told Popular Mechanics in 2009. "Here, I'm kind of king."
At SpaceX, Mueller got the chance to focus on the rocketry of his childhood dreams. For a dozen years Mueller was a vice president of propulsion engineering, and in May 2014 he took on the role of CTO, where he builds and manages the group of engineers at SpaceX responsible for propulsion.
To be sure, working at SpaceX came with perhaps as much stress as excitement. Musk recalled in 2017 the near-failure of SpaceX at the International Astronautical Congress in Adelaide, Australia.
"A lot of people really only heard of SpaceX relatively recently, they may think Falcon 9 and Dragon just instantly appeared and that's how it always was. But it wasn't," said Musk, referring to the current SpaceX rockets. "We started off with just a few people who really didn't know how to make rockets."
SpaceX almost ran out of money, Musk said. "I messed up the first three launches. The first three launches failed. And fortunately the fourth launch, which was, that was the last money that we had for Falcon 1. That fourth launch worked. Or it would have been — that would have been it for SpaceX. But fate liked us that day. So, the fourth launch worked."
SpaceX is now working to make it possible for humans to live on Mars, according to its website. Musk has said he hopes to get an unmanned cargo rocket with gearto the red planet by 2024. In November, Musk said it would be seven to 10 years before the first group of humans go to colonize Mars.
Building propulsion technology to go to Mars is a far cry from chopping down trees in Idaho. Reflecting on his career, Mueller says his success is due to a combination of his ability and luck.
"Find out what you are good at and find out what you love. Hopefully they are the same thing. Then make a career out of it," Mueller said in his commencement speech. "Ability plus luck equals success. If you have the ability, then luck is your opportunity. I was very lucky that I met the right visionary and because of my passion for rocket engineering I was invited to this opportunity that became SpaceX."
Added Mueller, "Steer your dreams and energies toward new, exciting frontiers."
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