Jul.18.2017 / 10:50 AM ET

Everyone thinks about becoming an astronaut when theyre young. Along with firefighter and dinosaur hunter, astronaut seems to be on every childs list of dream jobs. But when youre like me and your father is an astronaut, that childhood fantasy tends to linger.

I grew up in Houston, just blocks from NASAs front gate. And my father, Owen Garriott, wasnt the only astronaut on the block. Shuttle astronaut Joe Engle lived to our right, and Hoot Gibson, another astronaut who flew on the Shuttle, lived to our left. And there were other astronauts in the neighborhood, along with engineers who worked to fly the astronauts into space. With all the spacemen around me, it seemed no one had to decide to go to space it seemed everyone was going.

I assumed I would too.

But in 1974, when I was 13, a NASA doctor told me that he hated to be the one to break it to me, but since I would now need glasses, I was no longer eligible to be a NASA astronaut. I was crushed. I had just been kicked out of the club that I felt everyone else was a member of. After passing through the seven stages of grief, I made a plan. If I couldnt go by NASAs rules, I would build my own space agency! Of course, at the age of 13, there wasnt much I could do to make that happen. But my family and friends knew that going into space remained a key goal in my life.

A few years later, I was fortunate to discover what has become my passion and my career: video games. In high school, I wrote 28 different games and then began publishing a series of popular games that are still played to this day. With the money I made on the games, I invested in and co-founded a series of companies, often involving people who had left NASA. My goal with all of these ventures was to help make space accessible to civilians or, more specifically, for myself.

Most of these attempts to change NASA rules from the outside were failures. One near-miss was Spacehab, a company founded with the idea of creating a large pressurized habitat that would be transported into space in the Shuttles payload bay. We envisioned something the size of a double-decker bus that could take up to 40 private citizens at a time into space. The module flew. But sadly, NASA quickly nixed my plan, noting it had no intention of ever taking civilians into space.

My goal with all of these ventures was to help make space accessible to civilians or, more specifically, for myself.

My goal with all of these ventures was to help make space accessible to civilians or, more specifically, for myself.

Years later, I partnered with the people who ultimately broke open commercial spaceflight, including Peter Diamandis, best known for the X Prize; Eric Anderson, president of Space Adventures; and Mike McDowell, an exploration travel entrepreneur. We created a series of space companies and initiatives whose goal was to get civilians into space (or near-space, as was the case with Zero Gravity, a company that flies paying passengers, and, now, NASA payloads) on weightlessness-inducing parabolic flights aboard a specially modified Boeing 727.

One day, Eric Anderson and I were sipping red wine on my back deck in Austin, Texas, lamenting the fact that we did not yet have a vehicle that could get us into space. Suddenly, we had an idea. Why wait for someone to create this suborbital vehicle? Maybe the Russians would sell us seats on their Soyuz spacecraft, which could put us into orbit?

When we reached out with our request to Russias space agency, Roskosmos, they told us no, because it would cost a lot of money to determine if and how they could do that.

We took that as a qualified yes.

I paid the $300,000 they said they needed to determine if and how they could do it, and I fully expected to buy the first seat. This was in 2000, a year in which Internet stocks crashed. Roskosmos ultimately agreed to our plan, but since all my wealth was in Internet gaming, I could no longer afford to go. Sadly (for me), the first seat was sold to Dennis Tito, who had been pursuing his own spaceflight dream.

By 2007, I had built and sold another company, so I had enough money to book my own trip to space aboard Soyuz. I was scheduled to go up in 2008, but as you may remember, that was another year of economic tumult. So as I was preparing for my flight, my ability to pay for it was once again vanishing. To make matters worse, the Roskosmos medical team called to say that they had discovered an anatomical defect in my liver that rendered me ineligible for spaceflight. You cannot imagine the sadness I felt to be kicked off a flight that I had pursued for 30 years, especially since I wouldnt be getting a refund on the millions of dollars I had spent for the chance to go into space.

A few hours later, I got another call from Roskosmos. If I would agree to have surgery to correct my livers defective lobe, I might be cleared for flight.

The next Monday, I went under the knife for some serious surgery. The recovery took months, but it worked. I flew to Russia and began my training.

On October 12, 2008, I was launched into space aboard a Russian Soyuz TMA 13 alongside NASA astronaut Mike Fincke and cosmonaut Yuri Lonchakov. We spent 12 days in space, primarily aboard the International Space Station. While on the station, I completed a heavy load of medical and commercial experiments on visual acuity, bone loss, immune suppression, and protein crystal growth along with work for Seiko and DHL. The protein crystal growth experiments continue to this day, and I believe they hold significant economic and medical value. I remain a key participant in the growth of commercial space activities.

Oh, and remember my eyesight? As it turned out, I was the first person ever to fly in space after undergoing vision-correcting surgery. Not surprisingly, NASA was very interested in studying how my eyes would react in microgravity. So I became NASAs guinea pig. I went through extensive testing before, during, and after my time in space. I had no problems with my eyes and now NASA accepts people who have had this surgery as astronauts. The thing that had prevented me becoming an astronaut in the first place had become a major contribution our knowledge about the health effects of weightlessness.

Please do not call me a space tourist. I was not a tourist.

Please do not call me a space tourist. I was not a tourist.

Please don't call me a space tourist. I was not a tourist. I got the same training NASA (and Russian) astronauts get. In orbit, I worked hard to complete those experiments both to offset the high cost of my flight and, more important, to build the businesses that will take me (and you) back to space and ultimately help humanity escape the cradle of our existence.

Seeing Earth from space was a life-changing event for me. Looking back at our planet, I realized what a precious, finite, and fragile home we have a feeling some call the overview effect. The challenges and opportunities around the world are innumerable and go from the scale of an individual life to the health of the whole planet. There is much here to explore and take joy in doing. But as soon as my friend Elon builds us a rocket that will reach Mars, Im packing up the family and heading to a new world!

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NASA Said No to My Astronaut Dream, So I Found Another Way - NBCNews.com