LAS VEGAS ? With two prototype modules for a commercial space station already circling the Earth, Bigelow Aerospace is gearing up for a full-scale assault on space.

For the upstart firm, it?s about volume ? and not entirely in the sense of quantity or number of items sold. The company?sexpandable module designs are designed to offer low-cost commercial volume in space ? for rent or lease ? not only to private sector interests, but also to national space agencies.

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Entrepreneurial zeal

As ?Mr. B? explains, space is no longer viewed as largely the exclusive domain of large governments and satellite telecommunications companies. Emerging as a key ingredient of the future is the rise of the private sector, hungry to spur a new business case for space. An element of that entrepreneurial zeal is the establishment of commercial space habitats and complexes.

A visitor to Bigelow Aerospace in North Las Vegas will find it guarded by a no-nonsense security team, a welcoming force that?s part of the gated and sprawling complex.

As I strolled across the floor of the main Bigelow Aerospace construction building, I noticed the place is packed with test structures and fabrication tooling. But the true eye-catcher: full-scale, walk-in mockups of the firm?s three-person Sundancer module and the larger BA-330, a unit that offers 330 cubic meters of internal volume for a crew of six.

?I think you can only go so far on a computer design and on paper,? Bigelow told SPACE.com.

As we walked through the modules, Bigelow added, ?When you have three-dimensional structures you start to recognize things?from a user-friendly standpoint. It?s more satisfying to actually see things take shape.?

Astronaut visitors to the module mockups ?are flabbergasted by the volume...they are really taken back by how large these are,? Bigelow said. ?We are actually looking for a couple of astronauts now to join our marketing program.?

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One key item on tap for Bigelow Aerospace this year is constructing the A-3 building, Bigelow noted, a structure that will offer 265,000 square feet and is destined to be an assembly-line facility for the company?s spacecraft.

Beyond puffery

To seal the deal that, indeed, the dawn of expandable space structures has arrived and was beyond puffery, Bigelow Aerospace lofted in July 2006 and in June 2007, respectively, its Genesis 1 and Genesis 2 trial space modules, forerunners to the larger, human-ratedSundancer and BA-330 modules. The Genesis spacecraft were lobbed into orbit individually atop Russian Dnepr boosters ? a converted SS-18 ICBM ? from the Yasny Launch Base in Siberia.

That was then.

Bigelow is now eying 2015 as the year when the larger human-rated habitats will be in Earth orbit, ready for boarding. All that is predicated, however, on launch availability ? be it on an Atlas 5 or the yet-to-fly Falcon 9 rocket under development by private booster builder Space Exploration Technologies (SpaceX). It will take seven rocket flights, he said, to hurl the elements for the first Bigelow Aerospace complex into space.

Back up even more, Bigelow said, and 2015 is predicated on what is going to happen this year with NASA?sCommercial Crew Development (CCDev) initiative. In September of last year, Boeing and Bigelow Aerospace teamed up to submit a proposal to NASA, as did other groups, for the space agency?s Commercial Crew Transport System.

NASA has yet to make a decision in regard to CCDev selections.

?We remain very optimistic in regard to our partnership with Boeing and have been particularly pleased with the way the relationship has developed,? said Mike Gold, Director of Washington, D.C. operations and business growth for Bigelow Aerospace in Chevy Chase, Md. ?The positive interaction demonstrates that commercial crew is not exclusively limited to small or new entities, and that larger, more experienced companies such as Boeing have a vital role to play,? he told SPACE.com via email.?

Build the buildings

Meanwhile, Bigelow Aerospace is ramping up its outreach to prospective clients.

?For the last year our focus and concentration has been on contacting countries,? Bigelow said, and he looks forward to developing agreements to serve their needs.? ?We haven?t contacted the corporate world at all yet?there hasn?t been time.?

Bigelow said that there are iterations of different kinds of space modules that can be made available for rent or lease depending on client needs. ?We can supply them with as much volume as they want to have.?

The first complex is designed to be leased, with one module housing Bigelow Aerospace-supplied astronauts that will maintain the Earth orbiting facility for clientele.

?Our astronauts will take care of housekeeping chores,? Bigelow said. ?They?ll make sure everything is totally sanitary and very accommodating. That?s a big job in itself.?

The mission of Bigelow Aerospace ?is to build the buildings?to be occupied by geniuses that can do really interesting things in those buildings?and these buildings just happen to be in space,? Bigelow explained. ?We want to facilitate what the dreams of people are, whether they are national dreams or corporate ambitions.?

Bigelow Aerospace-built modules could well serve the Hiltons or the Marriotts of the world if they wish to establish space hotels. ?It?s not our business, but we?ll lease our spacecraft to them?same goes with, say, a movie studio,? Bigelow said.

Instant moon base

Given NASA?s plans to build a heavy-lift, Ares V-class booster, Bigelow said he?s got ?Big Bertha? spacecraft in mind that could fit such a beefy rocket. One expandable module on the drawing board provides 2,100 cubic meters of volume ? that?s twice the volume of the International Space Station.

Beyond low-Earth orbit, Bigelow Aerospace also has its sights on expandable space habitats for Lagrangian Point L1, partway between the moon and the Earth.

Lagrangian points are where all the gravitational forces acting between two objects cancel each other out and therefore can be used by spacecraft to ?hover? in one spot.

?If we can deploy and gang together modules in low-Earth orbit, you can do it in L1?and you are 85 percent of the way to the moon,? Bigelow said. In fact, one scenario Bigelow Aerospace has already blueprinted is the soft landing of a trio of attached BA-330 modules ? including astronauts ? on the moon.

The result: instant moon base, something the size of the International Space Station, Bigelow advised. The self-propelled base could even blast itself into lunar orbit, or move from spot to spot on the moon, he said.

?We would lease those lunar facilities to our clients. That keeps the price down. If we sell something instead of lease something, the price really jumps,? Bigelow said.

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Leonard David has been reporting on the space industry for more than five decades. He is past editor-in-chief of the National Space Society's Ad Astra and Space World magazines and has written for SPACE.com since 1999.