SpaceX CEO Elon Musk is known for his dream of colonizing Mars, but he isn't the only tech tycoon with big plans for humanity.

Jeff Bezos — Amazon's founder and CEO of the rocket company Blue Origin — has ambitions for the human race that are nearly as lofty as Musk's.

"Our ultimate vision is millions of people living and working in space," Bezos said during an press conference in September, right after he announced that Blue Origin would build a new rocket factory in Cape Canaveral, Florida.

Blue Origin's coming space tourism business is the starting point of Bezos' grander vision.

The company wants launch a space capsule full of paying customers about 62 miles over Earth, where they'd experience a few minutes of weightlessness. The capsule would then parachute back to Earth while the rocket lands itself vertically on the ground — preserving it for the next flight instead of crashing it into the ocean.

Reusable rockets would considerably reduce the cost of a launch, making space travel more affordable for people interested in booking a ride.

In November, Blue Origin successfully tested its concept: by launching and landing a rocket after releasing a capsule at the edge of space.

Blue Origin

SpaceX took reusable rockets a step further on December 21, when it landed a rocket back on Earth after it deployed several satellites into orbit — a much more difficult feat than Blue Origin's recent landing. (SpaceX's rocket was bigger, traveled higher, and moved much faster.)

Still, Blue Origin is also working on a much more powerful engine for its next generation of rockets. It could produce 550,000 pounds of thrust — five times more power than the company's current engines. For comparison, each engine on NASA's old Space Shuttles produced about 418,000 pounds of thrust.

Blue Origin's new engines could be flying as soon as 2017. The United Launch Alliance (ULA) — a company that puts satellites into orbit and carries supplies to the International Space Station — has already contracted Blue Origin to use the more powerful engines to propel its new Vulcan rocket.

ULA isn't launching humans into space yet, but that might change when it starts testing Vulcan in 2019.

Right now only six people live and work in space aboard the space station. So we've got a long way to go before Bezos sees his dream fulfilled: The rockets not only have to get safer, cheaper, and more powerful, but we also have to build the infrastructure to house everyone up there.