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Sunday, March 29, 2015

Space Exploration: Inflatable Habitat Ready for Space Station Trip

Credit: Bigelow Aerospace
Inflatable Habitat Ready for Space Station Trip:
According to Bigelow Aerospace, the demonstration of expandable space habitat technology supports NASA's plans in the realm of human spaceflight, which ultimately lead to putting boots on Mars. Developing a deep-space habitat is an important step along the path to the Red Planet, agency officials say.

Founded in 1999 by entrepreneur Robert Bigelow, Bigelow Aerospace has as a goal the creation of a new paradigm in space commerce and exploration via the development and use of expandable habitat technology. Expandable habitats are viewed as offering dramatically larger volumes than rigid, metallic structures as well as enhanced protection against both radiation and physical debris.
Hmmm. Inflatable space craft.

Seems I read something about this concept in The Planet Strappers by Raymond Z. Gallun:
Nelsen didn't listen anymore. His and Paul's attention had wandered to the largest color photo thumbtacked to the wall, above the TV set, and the shelf of dog-eared technical books. It showed a fragile, pearly ring, almost diaphanous, hanging tilted against spatial blackness and pinpoint stars. Its hub was a cylindrical spindle, with radial guys of fine, stainless steel wire. It was like the earliest ideas about a space station, yet it was also different. To many—Frank Nelsen and Paul Hendricks certainly included—such devices had as much beauty as a yacht under full sail had ever had for anybody.

Old Paul smirked with pleasure. "It's a shame, ain't it, Frank—calling a pretty thing like that a 'bubb'—it's an ugly word. Or even a 'space bubble.' Technical talk gets kind of cheap."

"I don't mind," Frank Nelsen answered. "Our first one, here, could look just as nice—inflated, and riding free against the stars."

He touched the crinkly material, draped across its wooden support.

"It will," the old man promised. "Funny—not so long ago people thought that space ships would have to be really rigid—all metal. So how did they turn out? Made of stellene, mostly—an improved form of polyethylene—almost the same stuff as a weather balloon."

"A few millimeters thick, light, perfectly flexible when deflated," Nelsen added. "Cut out and cement your bubb together in any shape you choose. Fold it up firmly, like a parachute—it makes a small package that can be carried up into orbit in a blastoff rocket with the best efficiency. There, attached flasks of breathable atmosphere fill it out in a minute. Eight pounds pressure makes it fairly solid in a vacuum. So, behold—you've got breathing and living room, inside. There's nylon cording for increased strength—as in an automobile tire—though not nearly as much. There's a silicone gum between the thin double layers, to seal possible meteor punctures. A darkening lead-salt impregnation in the otherwise transparent stellene cuts radiation entry below the danger level, and filters the glare and the hard ultra-violet out of the sunshine. So there you are, all set up."

"Rig your hub and guy wires," old Paul carried on, cheerfully. "Attach your sun-powered ionic drive, set up your air-restorer, spin your vehicle for centrifuge-gravity, and you're ready to move—out of orbit."

They laughed, because getting into space wasn't as easy as they made it sound. The bubbs, one of the basic inventions that made interplanetary travel possible, were, for all their almost vagabondish simplicity, still a concession in lightness and compactness for atmospheric transit, to that first and greatest problem—breaking the terrific initial grip of Earth's gravity from the ground upward, and gaining stable orbital speed. Only a tremendously costly rocket, with a thrust greater than its own weight when fully loaded, could do that. Buying a blastoff passage had to be expensive.
Of course, Gallun wrote in 1961, so we all know that his idea of a space craft made of cheap materials and dependent on recycled air (or air produced by plants grown on board) was . . . ahead of its time?

Credit: Bigelow Aerospace
Bigelow Aerospace seems to believe in the concept. Here's info about its B330:
B330 will have 330 cubic meters (12,000 cu ft) of internal space, hence its numeric designation. The craft will support zero-gravity research including scientific missions and manufacturing processes. Beyond its industrial and scientific purposes, however, it has potential as a destination for space tourism and a craft for missions destined for the Moon and Mars.
Flexible, expandable? Check. Self-sealing? Check. Solar power? Check. Ion Thruster power? Possible. Affordable? Umm. Still face that cost of getting the package to space. Perhaps a space elevator could help.

But, you might ask, why? Asteroid mining? It seems, in addition to mining rare earth elements from the ocean floor (see here), there is a movement afoot to explore asteroid mining for rare earth elements(and gold and other valuable metals). There are start ups looking into making this work, e.g. Planetary Resources. Most of these efforts seem to be directed at robot mining, but why not allow individuals driven by profit motive to get out there and try their hand at space mining?

Asteroid Mining:
Early evidence suggests that there are trillions of dollars' worth of minerals and metals buried in asteroids that come close to the Earth. Asteroids are so close that many scientists think an asteroid mining mission is easily feasible.
Plus, you know, freedom.


1 comment:

  1. Anonymous12:57 AM

    If they start to mine these asteroids close to earth could this disturbance of the asteroid cause it to re-shift it's orbit around earth and maybe make it crash into the earth?
    Heltau

    ReplyDelete