James Cameron is already putting into action a life-long dream to dive to the deepest part of our oceans — and now it appears that he may soon also fulfill a desire to explore the heavens as well. 

The 56-year-old "Avatar" director is rumored to be in possession of a $150 million ticket to fly around the moon and back. The entire journey would take 17 days and include a stopover on the International Space Station (ISS). The Virginia-based Space Adventures, which has arranged every privately funded trip to the ISS, is selling two seats on a Russian Soyuz spacecraft being designed for lunar orbit. The firm recently revealed that one "high-profile client" had reserved the first spot — with The Sunday Times of London leaking that Cameron is the mystery buyer.  

That the director would be interested in the journey is not surprising considering his past efforts to snag a ride into space. As MSNBC reports, Cameron underwent medical exams in 2000 in preparation for a trip to either to Russia's MIR or the International Space Station. Neither plan panned out, but this latest opportunity is a much juicier expedition. Only 24 people have ever seen the dark side of the moon. 

In a call last month, Space Adventures Chairman Eric Anderson said the top-secret passenger was someone who wants to make the trip a meaningful experience not just personally, but for all of humanity. "It [the passenger's mission] is something that is going to address an issue and a concept that is of great importance to the world,” he said.

Connecting the dots, Cameron was quoted in a recent interview with Cosmic Log, saying that if he was given the chance to hit space, he would go only for the "right reason."

"For me, the right reason is not just to sorta go up and do a few orbits and come back down and tell all my friends about it," he said. "It would be to make some kind of a film, especially in 3-D, that has an important message for some people."

"Ten years ago, I wanted to do that, but the message was that we needed to do long-duration space flight with the space station as a steppingstone to going to Mars. Now, of course, all the funding's gone from the Mars program, so it's kind of pointless to get people keyed up for something that's not going to happen. I'd have to find a reason, more than just being a tourist."

Sounds like he's the guy. We'll find out sometime in 2015 when Cameron is finally finished with the remaining "Avatar" films and Space Adventures has a spacecraft ready to send around the moon. Until then, remember: there's still one seat left for $150 million. Interested?