Posted on 03/08/2005 6:17:08 PM PST by KevinDavis
Space entrepreneur Robert Bigelow has been making quiet inroads into the development of Earth orbiting inflatable modules. The privately built and financed habitable structures would be available for research, manufacturing, and other uses, including lodging for future space tourists.
Bigelow Aerospace of North Las Vegas, Nevada is eying launch early next year of Genesis Pathfinder spacecraft – a shakeout of systems to be used on a full-scale inflatable space structure dubbed the Nautilus, and now referred to as the BA-330.
(Excerpt) Read more at space.com ...
I'm sure they are making these self-sealing against micro-meteor strikes, but what about cosmic ray protection? Give me some metal and structural integrity any time.
Somewhat similar is the "Airship to Orbit" (ATO) being developed by JP Aerospace http://www.jpaerospace.com/
Wonder if this will be as successful as Custer's experiment with the inflatable fort.
I'm sure they have that part taken care of
A couple of months ago I heard a talk by John Powell of JP Aerospace and he compared malfunction situations with the Shuttle to these balloon things. Basically, with the Shuttle if something goes wrong you have about 1/2 second to react with the correct action. With the balloons you have time to schedule a meeting to discuss the situation.
Cool....
Despite what this guy thinks, I believe these are referred to as "emergency life support bubbles" in SF and should be used only as such - for obvious reasons.
Actually this is technology that was being looked into by NASA but abandoned. Bigelow picked up NASA approval to continue with the program and hired the guy at NASA who was in charge of program development. He has an agreement with NASA that the original team will provide consult services. He's a billionaire with a dream. Hope he makes it work.
Tests show this design to be superior to metal in those respects.
"...superior to metal in those respects."
Interesting. I'm sure more details will become available as work progresses, but I'm still not sure how something inflatable could protect against cosmic rays as well as metal. A conductive mesh could act as a Faraday cage against EMP, but particles are another thing.
I read an article on this guy the other day in a magazine while flying. Sorry I can't remember the name of the mag but that's where I got the info on the characteristics of the material. Even NASA admits the possibilities of this material but they've become very conservative and unwilling to fly new technologies without an almost ironclad guaantee of success. They're more than happy to let entreprenuers tkae a shot at it though and if it proves out they'll be more than happy to throw big bucks at it. There's supposed to be a flight test of a solar wing in April, another technology NASA is interested in but unwilling to fund.
Thanks for this follow-up info. I've always been intriqued by technological advances and admire those of greater intellect than myself.
Thanks for this follow-up info. I've always been intriqued by technological advances and admire those of greater intellect than myself.
If you're worried about primary cosmic radiation, metal is no better than Kevlar, at least at the thicknesses we build spacecraft hulls from. In fact, metal is probably worse; since primary cosmic radiation is mostly heavy charged nuclear particles (helium and iron nuclei, among others) traveling at relativistic speeds, it generates a flux of secondary ionizing radiation when it hits metal through a kind of subatomic "spalling" process (the technical term for this is Bremsstrahlung radiation). Most of this secondary radiation is going to be nasty stuff like X-rays, so putting a thin metal hull around a crew in deep space is the same as putting them inside a giant Crookes tube (the dingus that generates the X-rays in a medical X-ray machine). Not good!
To beat Bremsstrahlung, you have three choices: 1) divert the primary cosmic radiation by generating a powerful electromagnetic field around your ship, 2) use a super-thick hull (e.g. rock) to soak up the Bremsstrahlung radiation, or 3) build your hull out of an organic material (i.e. plastic) that will not generate secondary ionizing radiation when exposed to cosmic rays. Since these inflatable hulls are constructed of reinforced plastics, they fit the bill for case 3.
As far as the cosmic rays themselves go, for short trips in low Earth orbit, no shielding against galactic particle radiation is needed. You're just not going to be up there long enough for it to hurt you that badly. For long trips, or for permanently-inhabited stations, the ship or station is going to need powerful electromagnetic shielding (for solar and cosmic particle radiation protection) or some sort of "storm shelter" where the crew can take refuge from solar flares, This could be as simple as an inflatable module filled with ordinary water (mined from the Moon of course). When a flare warning is sounded, the crew puts the ship on standby and rushes into a small compartment in the center of the water-filled module. The "storm shelter" compartment would contain food, water, hygiene facilities, and enough communications, monitoring, and control equipment to allow the crew to stay alive and in control of the ship until the radiation environment improves. The water surrounding them will soak up the incoming particle radiation and keep them perfectly safe until the storm "blows over", at which time they may emerge, power up the ship, and resume normal duties.
Thank you for spending so much time to educate me on these matters. The issue of secondary ionizing radiation never occurred to me. The water-filled storm shelter is also a new concept to me. Again, thanks.
My pleasure. I'm just glad it made some kind of sense!
New material may be shield for space trip
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