Orbital ATK is also participating in the NextSTEP program — and their approach to space habitats would redesign their Cygnus cargo craft as a habitat module that can be added to NASA's Orion spacecraft or a larger space habitat.

"The final piece [for the craft's development] is a deeper look into how cislunar could be extended in some commercial direction," said Bob Richards, the vice president of advanced programs at Orbital ATK.

John Elbon, vice president and general manager at Boeing, said now that we've learned to live and work on the space station, it's time to move farther out; spacecraft like Boeing's upcoming Starliner will help create a sustainable economy in low-Earth orbit, and later extend outward toward the moon. NASA's Deep Space Gateway programcould provide an anchor similar to the space station for the industry to expand outward. [Boeing's Starliner Space Capsule in Pictures]

But what are the logical steppingstones to extending that marketplace from low-Earth orbit, to the moon, and someday out toward Mars?

"I love when people … put the word 'logical' and 'new markets' together," Manber said. "It's not logical. There's no logic to this." Manber compared the industry to predicting how the internet would develop in 1985. "There has to be some degree of faith that our commercial marketplace, the way we do business in America, will come up with solutions, because it always has."

"It's a combination of reform, government as customer, getting the LEO economy going, and Earth observation, bettering life on Earth, increasing in-space services, looking to see if asteroid mining and projects like that are real, and having that leap of faith," he added.

Elbon had a different take: "Jeff and I have this discussion; I usually have the more pragmatic view of the situation, I suppose."

He cautioned that there's a lot of opportunities for companies to test things in low-Earth orbit, and that it's dangerous to overextend or dismiss the space station too early.

"I think it's important we don't gamble our future in low-Earth orbit with too much of a build-it-and-they-will-come kind of approach," he said. "ISS is the place right now where we have an incubator for those kind of commercial demands, and we need to keep that going as a place where companies who have potential ideas can test them out … if we pull the rug out from under [the space station's commercial capabilities] too quick, it will falter before it gets going. That transition, it's really important for us to think through and do properly."

Barton Bolfrass, the CEO of Fathom Academy, has an eye on providing workers for all these space enterprises — his company is set to build underwater training facilities so people can learn how to build habitats, repair satellites and do construction outside of spacecraft.

"We [at Fathom Academy] do not train Ph.D.s, we do not train pilots — we simply create a workforce for space," he said. "We are currently asking surgeons to build our hospitals in space. Just as it would be surprising to drive by a construction site and [see] surgeons or chefs building the hospitals or restaurants, we need scientists, but scientists need assistants. Officers need enlisted men, chefs need sous chefs.

"The biggest hurdle that our industry has been suffering from since we set foot on the moon is accessibility," he added. "People have to care about it to want to go and continue to do it, … [and] the excitement dies the moment you leave the ground without them. To be able to say that I have a chance to go, that I can go, that there's something for me to go to, that's where I think the commercial aspect of our industry will go from a trickle to a flow to an explosion of interest."

Richards pointed out that the U.S. opening the space station to commercial experiments as a national lab "jump-started gigantic amounts of small companies and new ideas … [and that] working closely with the government to come up with solutions is the right way to go there."

"I think the NextSTEP program is architected about right for the beginnings of that," he added.

The panel's moderator Jason Crusan, the director of NASA's advanced exploration systems division, which administrates NextSTEP, added that creating enough demand to build an economy in space while encouraging exploration, is a major focus and concern.

"Demand generation is probably one of the biggest things that keeps me up at night: What is that demand model going to be," he said. "There is no logical step. One of the things we're trying to do is build an ecosystem for economic experimentation. How do we set up, as a government entity, drop down barriers to entry, reduce cost to doing that experimentation, all the different things that we can do to allow an ecosystem for experimentation to occur outside the government.

"We're shifting the entire way we interact with industry," he added. "We're actually moving in concert together quite a bit — we can't go too fast, they can't go too fast; we have to kind of learn and experiment together."

Email Sarah Lewin at slewin@space.com or follow her @SarahExplains. Follow us @SpacedotcomFacebook and Google+. Original article on Space.com