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Fly To Mars In A Plastic Ship
saskboy writes "NASA reports that an old polymer may be the spaceship material of the future. Polyethylene is in household garbage bags, and it is also an effective solar radiation shield. I learned three years ago in astronomy class that polyethylene is used in the sleeping quarters on current orbiting space vehicles, but now NASA has developed a way to toughen the polymer into a product they call RXF1 which is 'even stronger and lighter than aluminum'. As you may know, radiation in space is currently a major obstacle to manned missions outside of the Earth's magnetic field, so better radiation shielding is essential to planned manned missions to Mars and beyond.
Get the mp3 podcast of the article here."
but now NASA has developed a way to toughen the polymer into a product they call RXF1 which is 'even stronger and lighter than aluminum'.
Is it transparent?? Plastic usually is/can be. Perhaps this is what they really meant by transparent aluminum. We should really make sure none of this time's whales have been recently stolen!
Why, no I didn't read tfa.
Plastics.
But, MP3 is so 1990s! Podcast is the new-millenium term!
Please, for the good of Humanity, vote Obama.
You can toss your spaceship in the blue bin for curbside recycling!
NASA has developed a way to toughen the polymer into a product they call RXF1 which is 'even stronger and lighter than aluminum'.
Yeah, and polyester hats should be much more fashionable than the tin foil ones.
In theory there is no difference between theory and practice. In practice there is. - Yogi Berra
With carbon fiber being as strong a steel at a fraction of the weight, and plastics that are bulletproof, and it becoming more and more likely that polymers will be used to build next generation cars, bridges and buildings as well as spacecrafts.
And what happens when you get too close to the Sun? Hmmm.
On the other hand, it would be great to use all those Coke bottles to go to Mars!
Evil people don't think they're evil. - George Lucas, Making of Ep III
Sorry to bring you up there, but my system weighs around 40kg now with the fluid cooling and it's anything but portable; even If I could work off with it, It'd rip the IEC out of the UPS after 4 feet.
Ripping an new rectum in the fabric of spacetime.
No, seriously, what's the point of a manned space flight to Mars? What can they do that robots can't? Is it really worth the cost and the risk?
Circumcision is child abuse.
Why in Bush's name are we cutting fuding to nasa? After this alumna-plastic and http://www.jpl.nasa.gov/news/features.cfm?feature= 490
aerogel, seems to me they are doing cutting edge USEFULL research.
Like the saying goes, never underestimate the bandwidth of a station wagon full of tapes. -Pyrotic
There is no risk to you.
Nobody is asking you to go to Mars and it just so happens that some people still have the spirit of exploration and adventure and will volunteer to go knowing the dangers involved. (I know this to be true because I would raise my hand for the chance).
If America can't find someone to volunteer and do it for the spirit of exploration, China, a few years later will order someone to do it for prestige.
Ripping an new rectum in the fabric of spacetime.
Y'know...I'm not the world's most intelligent guy, but it occurs to me that a plastic ship would be...intersting to pilot through an atmospheric re-entry. I for one would not like to be part of the crew of the USS Icarus as it found out the hard way why we don't make ships from plastic!
"I drank WHAT?!"--Socrates
RSS URL is feed://science.nasa.gov/podcast.xml, smartass
I am subscribed with the iPodder app. Again, how is this not a podcast?
--- Eat my sig.
"even stronger and lighter than aluminum"
Yeah, but really geeks want to know, is it transparent?
Just taking a look at TFA, it's quite clear that this is a link to an audio file (actually an M3U PL) rather than any mention of a podcast.
This would suggest the file is intended for listening by anyone, anywhere with a Mpeg 3 player thethered or not.
It seems that the term podcast in this case was applied solely by the submitter to Slashdot.
Ripping an new rectum in the fabric of spacetime.
Then we'll be mining those landfills...which sounds like an easier job than mining metals.
All sorts of weird future scenarios come to mind...a world where disposable utensils are made of glass or metal or something...because we need the polymers for more important things.
Blar.
Time to change my tin-foil for a polyethylene-foil hat?!
signal_connect(0, "test_top.dut.my_sig", "clk");
Damn, what was that sci-fi "spaceships of the future" book that I got back in the early 80s about where all the spaceships are made of "plastisteel"?
pi=sigma{n:0-infinity}[(1/16)^n][(4/(8n+1))-(2/(8n +4))-(1/ (8n+5))-(1/(8n+6))]
Plastics make it possible?
Goo goo g'joob.
It occurs to me that one of the cool elements of research like this is the potential for consumer-level spin-off products. I'm not a fan of the idea that we'll use more oil based products in place of metals for all kinds of things, so not sure how far I'd like this to go as far as spin-offs are concerned.
Good luck sometimes arrives disguised as bad
But most architecture just isn't that sensitive to weight. For example, steel frame houses have significant earthquake resistance and are just more durable overall. Most bridges cover modest spans and can continue to be steel and concrete. Further one has to consider the problem of wind force. If your structure is very light for its surface area, then it'll experience increased jostling due to wind. Then you need to engineer some sort of means for stabalizing the structure, maybe guy ropes or some sort of internal computer-controlled weight that counters these motions.
I'd want to see how the material handles long-term exposure to vacuum and large temperature swings before using it in any space-borne structural applications. Most plastics contain plasticizers that help improve flexibility and handling properties, but which slowly evaporate leaving the material brittle (anyone ever see what happens to a plastic milk jug left in the sun for a year?). Moreover, plastics tend to have structural properties that are very temperature sensitive -- at modestly high temperatures, plastics slowly stretch to failure, at modestly low temperatures, they fracture. The "temperature" in space is strongly dependent on whether the surface is facing the sun or not. It's baking hot on the sunny side and freezing cold on the shady side -- not a good environment for plastics.
The history of material science is the history of failures such as the catastrophic failure discovered in Liberty ship hulls in cold North Atlantic waters (learning that some steel alloys are brittle in low temperatures) to the Comet airplane crashes (learning that aluminum fatigues from repeat cycles of stress). I can only hope that NASA does something like LDEF with this material before depending on it to hold its properties for several years of space-exposure.
Two wrongs don't make a right, but three lefts do.
this may be a podcast
a sticspaceships/audio/story.mp3
:)
feed://science.nasa.gov/podcast.xml
but this is not:
http://science.nasa.gov/headlines/y2005/images/pl
smartass..
Looks like all that time making rockets out of washing-up-liquid bottles as a kid wasn't such a waste of time!
I'm off to send my CV to NASA... now where are my crayons?
Paul Leader
what's the melting point of the modified polyethelene? that would certainly bear into my deciding whetheer to make a space hull from the material.
"Forgive us our trespasses, as we forgive those who trespass against us." -Jesus Christ The Lord's Prayer
It would have to be freakin enormous. A field doesn't work like a mirror, bouncing the incoming radiation off - it slowly deflects or bends the path of the incoming radiation. That works fine on a planetary scale and the earth's magnetic field extends several planet diameters into space. Generating an earth sized magnetic field around a space ship would be no mean feat.
Oh well, what the hell...
Radiaion proof? I've heard of this stuff, it's dalekinium! http://www.google.com/search?hl=en&q=dalekinium&bt nG=Google+Search
This can only mean that there's life on Mars and Bush believes it mus be EXTERMINATED!
The U.S. really needs an English to Wisdom dictionary.
According to MatWeb, Ultra High Molecular Weight Polyethylene (UHMW-PE) has an ultimate tensile strength of about 40 MPa, while 7075 alloy aluminum has an ultimate tensile strength of 524 MPa . The article claims that this new PE-derived material has a tensile strength 3x that of aluminum. I find a 40x improvement in tensile strength a bit tough to believe.
Your design to a real part online: Big Blue Saw
For god's sake, he said it was an mp3 of the podcast, can you not read?
A computer once beat me at chess, but it was no match for me at kick boxing.
wouldn't heat be the main issue over radiation? it wouldn't be good if the plastic melts and take its original shape!
on the bright side if the spaceship gets damaged they can repair it with a bicycle repair kit.
You mean they have a fifth sense, like ESPN or something?
You can hold down the "B" button for continuous firing.
robots should go to mars first, unfortunately bots can be quite dumb, so it might be a good idea to have someone there who has less than 16 hours reaction time to react quickly.
I'm still trying to figure out what people mean by 'social skills' here.
Ah laddy, you don't have transparent aluminum in this time yet (star trek IV)! :)
Wow, stronger than alumninum and thinner. Sounds amazin!
...because what we really need is something that doesn't need gross bulk repairs but repairs itself at the microscopic level and only life does that. Our real goal should be techno-organics where the ship has more in common with plants and insects and heals itself. The bulk of such a thing would be shielding, structure, and so on all at once. Especially if the ship's water supply is also coursing through it as part of its "bloodstream" as it were.
I get the feeling we'll be also figuring out how to warp local spacetime as well right about the same time. Probably less than another forty years.
If my grammar and spelling are off, I am [distracted/tired/careless] (take your pick)
... welcome our new plastic-encased overlords.
i - This sig provided by
Actually this is going to make spacecraft a lot cheaper. NASA will be producing future vessels in kit form with components attached to a large plastic framework. Construction will be a simple matter of twisting off the right parts and gluing them in place.
the NASA research was actually for something useful, rather than something that subsidises corn or timber or some other lobby group.
It would be more useful to be building cars out of this.
"It's the height of ridiculousness to say for those 9 lines you get hundreds of millions."
Comment removed based on user account deletion
Quote from the article: "Flammability and temperature tolerance are also important: It doesn't matter how strong a spaceship's walls are if they melt in direct sunlight or catch fire easily."
I can imagine fleets of attacking Martian vessels with giant magnifying glasses all focussed on the NASA fleet of plastic spaceships - turning them into wobbling globs of soft plastic with tasty humans inside!
"Houston, we have a problem"
A lot of plastics I see tend to get brittle and disentigrate when exposed UV from the sun.
How well does polyethylene hold up when bombarded by radiation in space.
You may not die by radiation, but you may die because your spaceship popped.
doesn't have to be earth sized, the volume is much smaller so you just need small magnets lined up around the hull with the proper alignment of their magnetic fields. Essentially creating small runoff trenches for radiation to flow around the ship. Could be like an umbrella that is pointed towards the sun by a servo-robotic assembly, it has to deflect them less if it can do it from farther away.
The first rule of USENET is you do not talk about USENET.
Snap-Tite my arse, they always needed just as much glue as the others...
It's sad when choosing an installation directory on your own qualifies you as an "advanced user."
Polyethylene is almost never transparent because it crystallizes very easily with its nice simple ...-CH2-CH2-CH2-... backbone. The resulting microcrystals scatter light and make the stuff milky. If you want transparent polymers, you use a backbone structure that doesn't easily form crystals, for example polystyrene, where the big benzene rings tend to jut randomly left or right out of the backbone.
I would guess that their new form of PE is a variant on long linear PE, with reduced branching of the CH2 backbone. This is going to have an even greater tendency to form crystals (Indeed, the crystals may be an essential part of the high strength feature, because they tie different PE chains together.) So I very much doubt it would be transparent.
No metal can ever be transparent, Star Trek IV notwithstanding, because to be a metal is to have free electrons, and free electrons absorb a broad spectrum of light. Put it another way: if you're a metal, you're a conductor, or equivalently an antenna, and that means you absorb electromagnetic radiation, i.e. light. So you can't be transparent.
Has anyone actually listened to it? Oh my! I never knew high density polyethelene shielding of high energy cosmic radiation could be so faaaabulous sssweeetiessss! Who knew Carson Kressley has such a keen interest in astrophysics...
- "Hear that?! The percolations are imminent! Cease your ingress!"
I understand one of the disadvantages composite materials have, besides the fact that they cost more and are generally harder to work with, is that their aging and failure modes are hard to predict. If you build airplane or spaceship parts out of metal, you can do small-scale short-time testing of the material and accurately predict the lifetime of the part, its probable failure mode, how its properties will decline as it ages, and the warning signs of imminent failure.
This is not true for composites. Accurate theory to scale up small and short tests to the full design lifetime does not yet exist. Furthermore, composites tend to fail all at once, without warning, and sometimes in response to stresses that previously they easily withstood.
Recall the RSS panels on the Space Shuttle, which failed in Columbia and in the CAIB test under surprisingly small impacts. This is not, I think, because the original engineers had their heads up their asses and didn't design for an impact with a bird or some such. I suspect it's because these composite parts are now 25 years old, and subtle changes due to aging have ruined their original design impact resistance, and have opened up unsuspected new failure modes.
In other words, one of the big virtues of metals is that they are much simpler materials, and the ability to predict the performance of your material accurately is a nontrivial criterion in selecting it.
I wear both. The plastic hat to block solar radiation (alien beams) and the tin foil to block out radio waves (human beams).
You can never be too safe.
Get your Unix fortune now!
While plastics are incredibly useful and durable .. from a chemical point of view... I'm much less likely to trust them in terms of long term stability.
I've seen these things dissolve in the slightest bit of an organic solvent (e.g. Dichloromethane or acetone)... and seen them melt with a souped up hairdryer (heatgun) at less than 200 degrees C. I wouldnt feel particularly safe with these materials shielding me from one of the harsher environs known to man (space).
Maby it's just my experience of seeing these substances take damage a lot, but i'd be real uneasy to trust my life to them over a bar of aluminum, which you can easily dip in water/organic solvents and heat to rediculous heats without so much as loosing it's bright metallic glint, let alone the all important structural integretiy.
If they're going to use plastics as a main part of the airframe, they're definately going to have to do some shielding from heat/radiation (U.V. light by itself can be quite destructive to certain plastics).
As frequently happens with NASA tech, I expect this will make its way into the private sector.
How long will it be until they're packaging our scissors, walkmans, and USB hubs in this stuff? You thought those packages are hard to open NOW!
-- I prefer the term "karma escort."
He means it would have to be freakin' enormously strong, not necessarily large in extent.
Typical cosmic rays have energies from a few GeV up to a TeV, although some go astonishingly higher. To deflect TeV protons 90 degrees over a distance of 3 kilometers, the Fermilab Tevatron needs to feed thousand ampere currents into the world's largest superconducting magnets, each of which weighs hundreds of tons and must be cooled with liquid helium.
So it is utterly impractical to build a lab magnet to deflect cosmic rays.
Yeah but then you'd have to constantly divert power to the deflector shields. It'd be better if you could do it in a localized fashion, such as for only forward or rear deflector shields. However in a bind you might still have to cut power from life support, leading to undue tension between the captain and engineering.
Polyethylene is in household garbage bags, and it is also an effective solar radiation shield.
Oh sure...they all laughed at me for wearing garbage bags instead of clothes but now...NOW who's the one laughing! Mwhahahahahaha!
"Leo Fender was in a 'state of grace' when he designed the Stratocaster." -- Paul Reed Smith
If you'd been reading Slashdot years ago, you'd have noticed in my signature perhaps a pet foil hat, with a polyethylene lining - shopping bag - to increase effectiveness.
And you all laughed at me then.
Look who's laughing now?!
MUHAHAHAHAHAAHH!!
http://mirrors.meepzorp.com/ebay/pet-foil-hat/
Saskboy's blog is good. 9 out of 10 dentists agree.
Neutrons are the bad boys. They don't have a charge like protons (alphas) and electrons (beta) so they aren't easy to stop. What makes them nasty is that they are massive and can do some real damage.
Poly (and water) make the best neutron radiation sheilding because it has alot of hydrogen atoms (one proton nuclei) which when hit with a loose neutron, will cause the neutron to loose 1/2 it's energy (two equal mass objects remember). So after a few collisions with a few Hydrogen nuclei (protons), the Neutrons become slow enough to be absorbed into any handy atom's nucleus (hopefully NOT in your DNA)
THAT's why they use Poly sheilding in space craft.
Your thin skin doesn't make me a troll
...g.
9 &threshold=0&commentsort=0&tid=160&tid=14&mode=thr ead&pid=13418734#13419073
See my reponse for the details:
http://science.slashdot.org/comments.pl?sid=16028
Your thin skin doesn't make me a troll
So this stuff is a fabric, so the implausible tensile strength numbers are probably for the individual fibers, not for a solid piece of the material. (The photo has him holding a "brick" of the material though.) Spider silk is as strong as high strength steel, and is very tough, but no one is suggesting building spaceships out of it. 2.6 times less dense than aluminum gives it about a density of 1, which is what polyethylenes typically are.
So they've managed to build a tough fibrous material. That's good, and it might make for a good micrometorite shield, and possibly a radiation shield. But it's not going to be a replacement for steel, titanium, or aluminum.
The radiation safety field has been using plexiglass (polymethylmethacrylate) as shielding against high energy beta particles for decades so its not very surprising that another polymer of a similar type can be used to shield against intrastellar particles of a similar type. The thing to understand is that although they liken the structure to that of a garbage bag, the higher the energy of the particle, the thicker the material needs to be and since those particles have very high energy in space, it is likely you are going to have a ten foot thick garbage bag as your shielding in future space ships...
...and it should be known by now
Polyethelene might protect astronauts from solar and cosmic radiation, but it won't stop a Destructo-Ray or the infamous Zhti Ti Kofft!
The Uncoveror: It's the real news.
And a particularly swishy guy at that.
So if NASA is touting this new material as a boon to travel outside the Earth's magnetic fields, that implies that we didn't have much to do that in the past. But we went to the moon. Have i seen one too many Conspiracy Specials or does this sound like NASA genuinely didn't have enough radiation sheilding for manned missions to leave orbit before? -Squirrel
Give a man a fire and he'll be warm for a day. Light a man on fire and he'll be warm for the rest of his life.
The story said it was an "mp3 of the podcast" not a "podcast of the mp3". I fail to see your point.
--
WHO ATE MY BREAKFAST PANTS?
Mix together garbage bag material space habitats and Bruce Sterling's idea that you would _want_ cockroaches in order to eat the sluffed off skin and stuff and it looks like interplanetary settlements will be about as glamorous as I envisioned life in a vacuum-sealed can would be.
We've already sent robots - and they've done about what they can.
Every new robot sent is going to get increasingly fewer returns. What a human can do is - anything. They can climb down in a gully we want to go to now, without spending a few billion more on a craft that MIGHT make it to the surface. Just because NASA has had a lot of success does not mean each new robot is assured of a landing, and once there will not break - especially if you are going in a canyon (when you can easily slip or loose signal) that would be easy to get out of for a suited human with a partner and a rope.
Think of how much harder it would be to build a house if instead of sending humans over you ad a carpenter work remotley. Hell, even for gigantic structures like skyscrapers you have people all over them. Why can't that job just be done remotely by a robot? Because humans are just so much more flexible and smarter than a robot will ever be (for at least a hundred years or so).
That is why the time has come to send realy people instead of another robot. I'd be first in line, even if I knew the trip would be one way only. And I'm not the only one who thinks along those lines I'm sure.
"There is more worth loving than we have strength to love." - Brian Jay Stanley
It's an allusion to http://www.imdb.com/title/tt0061722/ (The Graduate).
If you haven't seen the movie, shame on you.
I've got mod points now, and I can't help but wish for an "Ouch! Burned him good, that dumb bastard!" mod.
:(
I'm so terribly disappointed.
What if the entire Universe were a chrooted environment with everything symlinked from the host?
it's only that traveling to the moon takes *much* less time than traveling to mars. that means the astronauts are exposed to less radiation...
See pictures of tits
...buying all those Lego toys from kid! now I can be the first to Mars by building a Lego spaceship!
But I also love the fact that you can get your PIN number is space and use it at an ATM machines in space!
;-)
Confused?
Get the mp3 podcast of the article here.
Or:
Get audio of article here
Or
Get MP3 of article here
The word podcast was complete redundant in that sentence. I mean, really.
If any word should be found #ditch shot execution style, it should be 'podcast'. Please, make it go away!
Back on topic: Compared to aluminum, polyethylene is 50% better at shielding solar flares and 15% better for cosmic rays.
You all know I have just ripped off my alufoil hat and placed a bin bag on my head right? wow... dizzy, feeling feint...
#hostfile 0.0.0.0 primidi.com 0.0.0.0 www.primidi.com 0.0.0.0 radio.weblogs.com
But out in space you have to contend with COSMIC RAYS, which are a whole other kettle of fish. They're much more energetic. So much so that if your typical plastic stops a cosmic "ray" (they're usually particles), the plastic emits a spray of even less desireable radiation.
Castpost podpost castpod mp3. Pod? Castpod postpod!
Wow, looks like the Chapulin Colorado is going to space, finally!
Hatredman
So when can I get my plastic bicycle?
ôó
From page 79 of Volume I of the CAIB Report:
"Several considerations influenced the overall RCC test design:
On page 83 we find some CAIB findings:
Further technical detail is provided earlier, on page 56:
One part of what you say is true: the original design specs did not call for any significant impact resistance. However, what the engineers produced did in fact have significant impact resistance. Not all of the impact tests produced holes, and it is unknown whether the foam impact would have busted a new RCC panel.
But it's clear aging is important to the material properties of the RCC, and also that NASA found it impossible to measure the effects of aging and predict a lifetime, and that they relied instead on an (apparently inadequate) analytical model to guess the aging and lifetime.
I can find no evidence that the CAIB concluded, as you say, that ageing played "no" role, and plenty of at least indirect evidence to the contrary, that they believed ageing did play a role, and, more worrisomely, that the effects of ageing complicated greatly any attempt to predict the response of the RCC to impact.
As I said, composite have wonderful properties, but one of the challenges in using them is predicting how those properties change with age. I think Columbia is a good illustration of that problem.
Here on Earth, we have a magnetic shield and an ocean of air. Is there much research on a magnetic shield for spacecraft?
-- Stephen.