WASHINGTON -- Now that millionaire space tourist Dennis Tito and his wallet are back here on terra firma, his gravity-breaking "fee for flea" flight has put into high gear more thinking about escape velocity vacationing for the rest of us.

How soon before we hear the pre-reentry request for back-of-the-seat tray tables to be stowed in their up and locked position?

Experts see a number of necessary steps before public liftoffs become a roaring business.

If space tourism is to become affordable and routine, it must start from the ground and work its way up.

The cost of a passenger-carrying rocket isn't the key issue. And it's not the fuel either, said Angie Bukley, an engineer for The Aerospace Corporation at Kirtland Air Force Base in New Mexico. The major expense of hurling payloads and people into space is ground support, she said.

Bukley's views were honed as co-leader of a space tourism study recently completed at the International Space University in France.

Like commercial aircraft of today, Bukley said, public spaceships of tomorrow require quick turnaround, with streamlined and simple ground operations. That keeps vehicle operating costs down -- as well as seat price, she said during the National Space Society 's 20th annual International Space Development Conference, held May 24-28 in Albuquerque, New Mexico.

And Dennis Tito aside, just how much is a future ticket-holder willing to plunk down for spinning around Earth?

"You can't get an idea of what people are going to pay until they know they can get it," Bukley said. Surveys indicate that the range people might pay is anywhere from a day's salary to a month's salary, to five to ten years of salary. "It depends on how you ask the question," she said.

"Asking a person if they want to go up to a place with a very harsh radiation environment, where they are likely going to throw up most of the time, and you might be sick or not be able to stand up when you get back downthen they answer the question a little differently," Bukley said.

Bukley said more medical data is needed about citizenry rocketed into space. "The only data we have right now is about people who are extremely healthy. Until Mr. Tito flew, we didn't have data on any person off-the-street," she said.

The reality of the situation today is that pushing passengers into orbit is limited, Bukley said. "There are only two ways to get people into space. That's on the space shuttle or using the Russian Soyuz rocket. That's it. So we've got a little bit of work to do there," she told SPACE.com.

One step to cultivate space tourism, Bukley suggested, is to offer long-duration, sky-high balloon flights of people-packed modules. Cruising at the edge of space, tourists could see the curvature of Earth and the blackness of space from altitude at affordable prices. Furthermore, by letting loose the gondola, the aeronauts would experience free-fall conditions for several minutes prior to parachute opening and soft touchdown, she said.

How quickly public space trekking will evolve is hard to say, Bukley said. There are too many variables that can shape the speed at which pay-per-view space tourism becomes reality, from economy and politics to cleaning up the planet and population growth. No doubt, a partnership between industry and government is needed, she said.

Bukley, like many space tourist aficionados, expects incremental growth in the business of propelling the public into orbit.

"We need a market that demands high volume and frequent launches," said Peter Diamandis, chairman, president and founder of the X PRIZE, based in St. Louis, Missouri.

"Unless you are talking about people, you are missing the boat. We have got to start thinking about self-loading, replicating payloads that come with money, and those are called people," Diamandis said.

Diamandis said there is an "inherent fear" in the industry to think about launching people. "We need an environment that allows and rewards risk in innovation. The X PRIZE is about allowing people to think out of the box, pursue crazy ideas and have a little bit of risk taking," he said.

The X PRIZE is a $10 million purse to jump-start the space tourism industry through competition between teams of entrepreneurs and rocket experts around the world. The cash goes to the team that designs the first private spaceship which successfully lofts three humans to a suborbital altitude of 62 miles (100 kilometers) and back on two consecutive flights sandwiched in within two weeks. All teams must be privately financed.

Opening its doors several years ago, however, the X PRIZE reward has been more a promissory note than actual cash-on-hand. Diamandis said efforts are now being redoubled to raise the full purse.

The X PRIZE idea has been embraced by teams all over the globe. In January, the 20th entry accepted by X PRIZE officials was announced. The Canadian Arrow concept incorporates technology from rocketry built in the 1940s, said Geoff Sheerin, team leader of the project.

Nearly six stories tall, the Canadian Arrow joins other vehicles of all shapes and sizes now being readied around the planet in the hopes snagging the $10 million prize.

Courtesy of Dennis Tito's ascent and return from orbit, the era of extraterrestrial space tourism will take off in earnest once we gather a bit more market research.

That's the view of Geoffrey Crouch, professor of tourism marketing at the School of Tourism and Hospitality at La Trobe University in Australia. Tito satisfied a hunger likely shared by wannabe space travelers everywhere. Space, the universe and humankind's minute presence in it is an acute human fascination, he said.

"The idea of being able to look down on the surface of the Earth from space, with its thin atmosphere sustaining life, and floating in a black void with trillions upon trillions of stars and galaxies far beyond, is an imagined experience that generates passion and excitement in everyone," Crouch said.

Nevertheless, putting spectacular scenery aside, Crouch asked: "If space travel and tourism were available to the public, how many could and would participate?"

In the last decade, studies by researchers in Japan, the United Kingdom, Canada, Germany and the United States have estimated the likely scale of demand for space tourism. The good news is that the results are consistent and positive. However, several questions and doubts remain, Crouch said.

"Although these studies are a start and may help to alert financial markets to the potential of investing in space tourism, they are unlikely alone to be anywhere near sufficient to convince Wall Street at this time," he said.

What's needed, said Crouch, is extensive and rigorous research of the space tourism market. "Its shape, size and growth will be determined by the products, prices, competition and strategies developed and adopted by commercial space interests, guided by solid market research and resulting marketing strategies," he said.