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Nuclear Powered LEDs For Space Farming

Unknown Lamer posted about a year and a half ago | from the 1950s-science-strikes-back dept.

Space 287

DevotedSkeptic writes with an interesting article on possible lighting sources for growing food on the moon and other off-world locations. From the article: "... Agriculture remains the key to living and working off-world. All the mineral ore in the solar system can't replace the fact that for extended periods on the Moon or Mars, future off-worlders will need bio-regenerative systems in order to prosper. Here on earth, researchers still debate how best to make those possible, but nuclear-powered state of the art LED technology is arguably what will drive photosynthesis so necessary to provide both food and oxygen for future lunar colonists. ... Although during the two weeks that make up the long lunar day astronauts might be able to funnel refracted sunlight into covered greenhouses or subsurface lava tunnels, they will be left without a light source during the long lunar night. Current solar-powered battery storage technology isn't adequate to sustain artificial light sources for two weeks at the time. Thus, the most practical solution is simply to use some sort of Radioisotope Thermoelectric Generator, not unlike the one powering the current Mars Science lab, to power the LEDs that will spur photosynthesis in lunar greenhouses. ... On earth, Mitchell says it takes roughly 50 square meters of agriculture to provide both food and oxygen life to support one human. But, as he points out, who can say how productive plants are ultimately going to be on the moon, in gravity that is only one sixth that of earth?"

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287 comments

We should know this already... (5, Insightful)

Anonymous Coward | about a year and a half ago | (#41220689)

We should freakin know how well plants grow in gravity based on the nearly 3decades of shuttle experiments... Did this Mitchell not bother to look that up?

Re:We should know this already... (3, Interesting)

scdeimos (632778) | about a year and a half ago | (#41221043)

Gravity isn't a problem, that's not what the article is about. The article is talking about how NASA is finally researching LED-powered greenhouses to provide light for plants in a lunar environment, even though greenhouses on earth have already been doing it for at least a decade. There are also high-hundreds/low-thousands of marine aquarists out there that have been doing it for some time, using red-blue LED panels to grow turf algae in their sump tanks for nitrate export.

Re:We should know this already... (1)

kelemvor4 (1980226) | about a year and a half ago | (#41221437)

Gravity isn't a problem, that's not what the article is about. The article is talking about how NASA is finally researching LED-powered greenhouses to provide light for plants in a lunar environment, even though greenhouses on earth have already been doing it for at least a decade. There are also high-hundreds/low-thousands of marine aquarists out there that have been doing it for some time, using red-blue LED panels to grow turf algae in their sump tanks for nitrate export.

That may not be the point of the article, but it does flat out question how plants will grow in low gravity. It's even in TFS:

But, as he points out, who can say how productive plants are ultimately going to be on the moon, in gravity that is only one sixth that of earth?

Re:We should know this already... (5, Funny)

Joce640k (829181) | about a year and a half ago | (#41221079)

Never mind the lettuce, what about the cows? How will cows stand up to low gravity? How will they grow enough grass to feed them? The ISS hasn't provided any experimental data on this.

Re:We should know this already... (4, Funny)

Anonymous Coward | about a year and a half ago | (#41221205)

Never mind the lettuce, what about the cows? How will cows stand up to low gravity? How will they grow enough grass to feed them? The ISS hasn't provided any experimental data on this.

Cows should be fine, because they can jump over the moon.

Apparently.

It's the little dog I'm worried about.

Re:We should know this already... (1)

somersault (912633) | about a year and a half ago | (#41221215)

McDonalds are probably at work on it right now :)

But really we want pigs. Can't make a BLT without pigs.

Re:We should know this already... (2)

jd2112 (1535857) | about a year and a half ago | (#41221397)

The pigs are already in space. Just look for the Angry Birds and you will find the pigs nearby. Plenty of bacon for everyone!

Re:We should know this already... (1)

Joce640k (829181) | about a year and a half ago | (#41221519)

But really we want pigs. Can't make a BLT without pigs.

You could even exercise them on big hamster wheels to:
a) Improve the flavor
b) Provide some electricity for growing the L+T

Re:We should know this already... (0)

Anonymous Coward | about a year and a half ago | (#41221591)

No shit. There is no reason whatsoever to go to Mars if you can't enjoy bacon there. Even Columbus took pigs with him.

What are we savages*?

* To answer my own question: if I were on Mars and there were no pigs, I have heard that humans taste like pork. If NASA doesn't want cannibalism on Mars then they better plan ahead.

Re:We should know this already... (3, Interesting)

TheLink (130905) | about a year and a half ago | (#41221355)

To me the real early steps to progress would not involve the Moon or Mars, but space stations with artificial gravity and radiation shielding.

Then you can actually have people, animals, plants etc living AND reproducing in space as opposed to trying not to degenerate so fast.

Trying to settle on the Moon and Mars without such stuff is like trying to jump before even being able to stand.

So from my perspective NASA etc nowadays are mainly a waste of resources. They're not really working on the necessary steps for the long term survival of the species in space. They're just sending expensive toys to mars and other places.

p.s. fish would probably do ok in low gravity, and some live on algae which doesn't need very much. You're going to want to have tons of water around anyway, so might as well put fish in at least some of it and filter the water when you want to use it for other stuff.

Re:We should know this already... (2)

Joce640k (829181) | about a year and a half ago | (#41221423)

So from my perspective NASA etc nowadays are mainly a waste of resources. They're not really working on the necessary steps for the long term survival of the species in space. They're just sending expensive toys to mars and other places.

I dunno. I think a lot of the stuff they do is a waste of money (the ISS, anything to do with sending humans into space) but they're the only ones doing anything at the moment. That alone is worth $5/person/year.

Re:We should know this already... (5, Insightful)

fuzzyfuzzyfungus (1223518) | about a year and a half ago | (#41221649)

Trying to settle on the Moon and Mars without such stuff is like trying to jump before even being able to stand.

I'd argue entirely to the contrary: Open space, from anywhere in high-enough-so-the-atmosphere-doesn't-get-you earth orbit out to the darkest edges of nowhere where Azathoth lurks in the dark places between the stars, is about as hostile an environment as one can reasonably imagine operating. Other than a reasonably steady supply of photons there is nothing there that you didn't bring with you(at considerable cost).

By contrast, any planet that isn't actively trying to murder you(eg. Venus and Mercury probably aren't at the top of the list) has massive amounts of potentially useful elements in the same gravity well as you. Just lying there for the taking. An overwhelmingly less hostile situation; but with more scientific novelty than just building a mockup in some place cold and dusty.

Satellites are crazy useful to the inhabitants of the planets that they orbit; but actually putting humans on them is a waste of time and space(with the one quite specific exception of doing low and zero-g medical research, which you can't easily do under other circumstances.

If you want cool planetary research, spewing robots at interesting planets is very likely the cheapest way to get it. If you want human populations that aren't on earth, colonizing objects that come with large amounts of free matter, and maybe even an atmosphere, rather than building teeny little bubble-capsules is overwhelmingly more practical. If you want to do research on long-term closed-system design and engineering, it's probably a waste to leave earth at all. Just buy up a bunch of warehouse space somewhere cheap, and you can run a dozen simultaneous experiments on earth for less than you could a single experiment in earth orbit(plus, if something goes wrong, you can just scrub the experiment, open the door, and resupply from home depot, rather than having to resort to mass deaths or heroic measures....)

Really, the only reason to have humans in open space for any nontrivial period of time would be research on how to deliver them reasonably safe and intact to an eventual planetary colony elsewhere(which may or may not actually involve sending humans at all. If team biotech can get amniotic tubes working, there would be some major benefits in just shipping a big cryo-flask full of iced zygotes, rather than dealing with adult astronauts....)

Re:We should know this already... (1)

TubeSteak (669689) | about a year and a half ago | (#41221547)

Never mind the lettuce, what about the cows? How will cows stand up to low gravity?

The more important question is can they jump hard enough to achieve escape velocity.
There's no point in bringing any animal to the moon if it can head back to earth under its own power.

Exactly! (4, Interesting)

captainpanic (1173915) | about a year and a half ago | (#41221163)

Exactly! We should be setting up a farm on the moon. Just to test it out. Start small: 1 m2 of soil in a greenhouse.

The cost of such a mission is for a small part related to the cost of the boosters to get things in orbit and to the moon, and for a large part to the over-engineering that NASA is doing. That over-engineering is caused by a fear of failure. It's not like it's rocketscience to get anything to the moon. The fear of failure is the only thing that seems to hold us back.

If it costs 5000 $/kg to launch anything into a high orbit (which I will equate with getting it to the moon), a decent sized farm (1000 tons of material) would cost 5 billion $ in launch costs, which is nothing.

We could set up some practice greenhouses for a fraction of the cost. If failure is an option, that should be cheap enough in an age when more than that is spent on warfare every day...

Re:Exactly! (1)

Anonymous Coward | about a year and a half ago | (#41221331)

Excellent idea (no kidding). That is how you learn to do things. The current science experiments on the ISS serve no purpose in learning how to live in space long term.

Problem is that no space agency currently thinks in terms of doing practical things. Build it and try it - not allowed - that isn't 'scientific'. Science on the ISS has been and still is an endless series of little experiments that have no practical application. They all end up as science papers and PhDs. After 50 years in space we still have no idea how to practically live in space for long periods separate from Earth. The ISS doesn't count - it is, for all practical purposes, still an open system that has to be replenished from Earth. The ISS is within hours (or probably less in an emergency?) from Earth. The astronauts do not have to deal with what happens if someone gets ill or dies with no immediate recourse to help from Earth.

I don't envy them if they ever have to face grisly details and I'm pretty sure I'll handle it badly. But it will become part of life on long space journeys. Someone dies or gets injured horribly - what if an autopsy is required? I'd rather walk out an airlock without a suit than have to cut someone up.

Etc, etc. We need to start doing things properly in space. The fact that there has been very little real construction problems in space is a monument to these people's ingenuity. But it makes me wonder - if we can figure out how to carry out the construction in every fine detail years before the time, how much have we really learned from actually working in space?

Re:Exactly! (1)

Henour (1513727) | about a year and a half ago | (#41221563)

Exactly! We should be setting up a farm on the moon. Just to test it out. Start small: 1 m2 of soil in a greenhouse.

The cost of such a mission is for a small part related to the cost of the boosters to get things in orbit and to the moon, and for a large part to the over-engineering that NASA is doing. That over-engineering is caused by a fear of failure. It's not like it's rocketscience to get anything to the moon....

Well it IS rocket science :D

Huh? (3, Insightful)

rs79 (71822) | about a year and a half ago | (#41220709)

"Current solar-powered battery storage technology isn't adequate to sustain artificial light sources for two weeks at the time"

Oh rly? Use enough Tesla power packs and they'll be fine. Lithium is light.

"But, as he points out, who can say how productive plants are ultimately going to be on the moon, in gravity that is only one sixth that of earth?"

Other than the fact we know already and that plants could be grown in earth gravity in a centrifuge yeah, good point.

Sheesh.

Re:Huh? (-1)

Anonymous Coward | about a year and a half ago | (#41220737)

Sorry, but your ass is too good to resist. I'm going to slurp it until it's covered in saliva. By the time I'm done feasting upon your ass, there'll be no ass left to feast upon!

Woooooooooooooooooow!

Re:Huh? (1)

Lisias (447563) | about a year and a half ago | (#41220829)

"But, as he points out, who can say how productive plants are ultimately going to be on the moon, in gravity that is only one sixth that of earth?"

Other than the fact we know already and that plants could be grown in earth gravity in a centrifuge yeah, good point.

And these centrifuges of yours will be powered by what? Hamsters?

Re:Huh? (0)

Anonymous Coward | about a year and a half ago | (#41220907)

Dude. It's space. Vacuum. No Air drag. The centrifuge will spin for a veeeery long time once it's started.

Take an ordinary space ship and make it spin. Voila - simulated gravity.

Re:Huh? (0)

Anonymous Coward | about a year and a half ago | (#41221175)

"ordinary spaceship" for the human race right now are Apollo space capsules. OK? Understand? Not the fucking USS Enterprise. So tell me, how fast do you need to spin it for 1G, and how much stuff can you grow in there?

Dude. It's reality. Vacuum. Nothing in it. No Star Trek.

Not as long as you might think. (0)

Anonymous Coward | about a year and a half ago | (#41221691)

Try spinning a raw egg. Now boil it and try again.

Solid centrifuges will spin for a very long time (nearly forever), but as soon as you put a gas in it the gas begins causing it to slow down. Gas at the rim is moving fast, Gas closer to the axis is moving slower.. When the two meet they average their speed --- and when the slower gas meets the rim it slows the rotation.

Same thing happens with the earth.. but so much of the earth is so nearly solid (and air such a thin layer) that the moon has more of an effect with the oceans.

Re:Huh? (0)

Anonymous Coward | about a year and a half ago | (#41221111)

Given the low resistance you can achieve in space, once you got it going, yes, a hamster could do it.

Re:Huh? (1)

Joce640k (829181) | about a year and a half ago | (#41221509)

And these centrifuges of yours will be powered by what? Hamsters?

Maybe the space pigs (are we really going to grow lettuce and tomatoes but have no pigs around?)

OTOH they might use a bit of the electricity the summary was talking about. With no air friction a centrifuge wouldn't need much to keep it going once it was started.

Re:Huh? (1)

K. S. Kyosuke (729550) | about a year and a half ago | (#41220921)

Oh rly? Use enough Tesla power packs and they'll be fine. Lithium is light.

I was thinking the other day about a thermal accumulator - dig a hole, build what basically amounts to an insulated vessel, heat it up during the solar day, and during the solar night, use the accumulated heat to power some heat engines. On a larger scale, it should be more efficient than batteries (the larger the vessel, the smaller the heat loss compared to the total capacity).

Re:Huh? (-1)

Anonymous Coward | about a year and a half ago | (#41221121)

...yes, and we will build that with no infrastructure, in an alien environment, while our cheap energy is running out. Pull your head out of your ass, space fantasies will not save us.

Re:Huh? (0)

Anonymous Coward | about a year and a half ago | (#41221269)

I agree. Let's not ever dream, or try to do anything that seems impossible. If man were meant to fly he'd have wings.

Re:Huh? (0)

Anonymous Coward | about a year and a half ago | (#41221401)

But that's the thing. It's not a dream, it's engineering. And it can be shown that it won't happen, because we don't have the energy or materials. And by your logic, we could dream about anything, and insist it should be real, right? And we don't have wings, we have arms and legs. We built machines that fly. We'll need to build machines for every single one of your space fantasies... So build away. You've only had half a century so far!

Re:Huh? (1)

cornjones (33009) | about a year and a half ago | (#41221161)

Hmm.... so many problems, where to begin...
1. 50 square meters of vegetation per person. HOw are you going to build a structure large enough to do all your planting?
2. I see the snark remarks about getting your centrifuge spinning in a vacuum but you are providing oxygen and food. how are you going to get oxygen and food in and out with out appreciable loss of energy? (and gardeners, fertilizer, seeds. wait, where is the fertilizer coming from? capturing the astro port a potties will help but you will need a good deal more than that.)
3. You are talking about building huge lithium batteries. How are you getting that much lithium off the planet? I do like the heat battery idea mentioned in a few posts down, throw in some mirrors to concentrate and you have a battery of sorts without requiring a lot of material.
4. Materials is a huge issue. Anything we can build out of rock we need to bring (at least until we have fabrication set up). That is hugely expensive.

Fiber Optics and realistic nuke power (1)

Anonymous Coward | about a year and a half ago | (#41220715)

Two technologies that would actually help would be massive bundle fiber optics, we have the tech now especially if mirrors are used to intensify the sunlight.
Nuclaer TEG's are all that work for lightweight probes, but for a real base station a much better heat exchange could be made on site to properly use the thermal output of the precious and heavy nuclear fuel.

strawberries (1)

mister.woody (2712229) | about a year and a half ago | (#41220721)

I usually do not buy strawberry from south America (just because I like to support local farms and I tend to believe that it is healthier as well). I have strong problems to buy strawberries that come from Mars.

Re:strawberries (-1, Flamebait)

Inda (580031) | about a year and a half ago | (#41220773)

I don't buy feather arse ticklers from South America!We have so much in common. Let's exchange Facebooks.

Overlooking a bigger problem? (1)

Apothem (1921856) | about a year and a half ago | (#41220733)

Last I checked, a lot of biological systems stop working when you dont have gravity. Especially things like immune systems. So if this is the case, I think light would be the least of your worries.

Re:Overlooking a bigger problem? (0)

Anonymous Coward | about a year and a half ago | (#41220815)

Why would the moon not have gravity? And: what about the idea of using a space elevator on the moon? Then you could put your farms at the end of the tether - with a long enough tether, you may be able to increase the radius enough to increase the centripedal acceleration to a sufficient level.

Re:Overlooking a bigger problem? (-1)

Anonymous Coward | about a year and a half ago | (#41220851)

Last I checked,

Maybe you should have checked in a library instead of your arse.

Re:Overlooking a bigger problem? (1)

wvmarle (1070040) | about a year and a half ago | (#41220993)

The moon and Mars have gravity - albeit less than Earth. No idea whether that's enough.

OTOH I wonder how well those plants do in absence of a complete ecosystem. Thinking of our own bodies, we have more foreign microbe cells in our gut than we have cells of our own. Without those bacteria we can't survive, we need them to digest our food. Healthy soil, the kind that provides nutrients to plants, is also teeming with microbial and insect life. I really wonder how well plants do without all those other life forms.

I don't know much about plants in that respect - are they really stand-alone organisms that don't need the help of any others?

Re:Overlooking a bigger problem? (1)

bickerdyke (670000) | about a year and a half ago | (#41221189)

The dutch have years of experience with hydroponic farmhouses and it works well enough for them to sell vegetables all over Europe. The downside is that some of them TASTE more like water than like the fruit they're supposed to be, but that most likely is due to selection on how they look in the grocery store. (You've usually already bought them when you get to the taste)

Put your habitat at the lunar poles (2)

MichaelSmith (789609) | about a year and a half ago | (#41220783)

If you build a habitat at one of the lunar poles it will be possible to build photovoltaic power plants which are both in sunlight and close enough to the habitat to directly feed power to it with electricity transmission lines. Additionally, this makes it easy for a habitat to be accessible for polar orbiting spacecraft. Habitats anywhere else on the moon move way from the orbit of your vehicle with the rotation of the moon. If your landing site is on the equator, then you can use an equatoral orbut, but for landing sites away from the poles or equator the orbitor continually moves away from the landing site, requiring that place correction manoeuvres be done before landing or docking with a returning vehicle.

Faith over facts (0)

Anonymous Coward | about a year and a half ago | (#41220795)

Space Lunacy ....

taste like? (0)

Anonymous Coward | about a year and a half ago | (#41220803)

We already have tomatos from Holland and Spain which all taste like crap. I don't even want to imagine what a moon tomato tastes like.

Re:taste like? (2)

Dr_Barnowl (709838) | about a year and a half ago | (#41220881)

The reason they taste like crap is not just because they were transported, but because they are varieties that have been selected for their longevity so that they can be transported.

Given that the tomatoes will probably be left on the vine until they are consumed, there's no reason to use the crappy modern supermarket tomato varieties - they can use heirloom breeds [wikipedia.org] . There's always been a high emphasis on morale considerations in the American space programme, and food has always been one of the things that they pay attention to for morale purposes.

Lots of useful information in there... (4, Interesting)

Firethorn (177587) | about a year and a half ago | (#41220817)

First, I've never heard the 50 sq meters (538 sqft) to sustain 1 human before. It's about the same area as an ultra-efficiency apartment. I assume that's for high-efficiency hydroponics. Interesting. I wonder if it'd be possible to grow some sort of edible algae to suppliment the more traditional crops? IE have an intense 2 week growing season, harvest when the sun goes down, then reseed when it comes back up? That would reduce the need to use your nuclear generator to keep the plants alive/in the proper growing cycle.

The gravity might mean you needing a slightly different breed, but given what I've seen with hydroponics/areoponics, I doubt that 1/6th gravity will have that much of a negative effect - but that would be something for the ISS to figure out!

Re:Lots of useful information in there... (0)

Anonymous Coward | about a year and a half ago | (#41220891)

I would be willing to bet that somewhere among the thousands of species that we use for food crops is one that can already tolerate a life cycle like that. I bet there's something that would be happy living through two weeks of dim light or darkness, followed by two weeks of supercharged productivity. If one doesn't exist, we could certainly create one.

I don't think you'd have to rely on algae and reseed from scratch at the start of every growing day. The night time would be a period of lower power availability, not of complete darkness, so you might be able to spare a few watts here and there to keep some larger, complex and tasty plants alive through the long night.

Re:Lots of useful information in there... (2)

djsmiley (752149) | about a year and a half ago | (#41221153)

rhubarb. It grows in the dark and you can HEAR it.

Re:Lots of useful information in there... (0)

Anonymous Coward | about a year and a half ago | (#41221629)

In space, no-one can hear the rhubarb grow.

Re:Lots of useful information in there... (1)

Dr_Barnowl (709838) | about a year and a half ago | (#41220913)

That would reduce the need to use your nuclear generator

It's a nice idea, but an RTG can't be shut down, as it works from radioactive decay heat.

I see a larger problem being the lack of the plutonium-238 required to make them. Some of the last of it went up with the Curiosity rover, and they had to scrounge that from the Russians [stuff.co.nz] .

Re:Lots of useful information in there... (0)

Anonymous Coward | about a year and a half ago | (#41220937)

Plutonium-238 is just one isotope particularly suitable for deep space probes. There are plenty of other isotopes also suitable for RTGs if design parameters (weight, radiation impact/shielding) are different or can be relaxed - which is certainly the case on moon colonies.

Re:Lots of useful information in there... (1)

Firethorn (177587) | about a year and a half ago | (#41220957)

Wasn't proposing shutting down the RTG, more 'you need a smaller one for the number of people you have". If you can get 50% of your food and O2 needs from the algae, that's 50% fewer other crops you need. I mentioned algae because it's about the shortest lifecycle for photosynthetic Iife I know. I don't know of any other food crops that can handle 2 weeks of light followed by 2 of night.

Re:Lots of useful information in there... (1)

Ash Vince (602485) | about a year and a half ago | (#41221615)

That would reduce the need to use your nuclear generator

It's a nice idea, but an RTG can't be shut down, as it works from radioactive decay heat.

I see a larger problem being the lack of the plutonium-238 required to make them. Some of the last of it went up with the Curiosity rover, and they had to scrounge that from the Russians [stuff.co.nz] .

Not scrounge, buy. It also wasn't the last of it. NASA has enough to last until 2022.

http://en.wikipedia.org/wiki/Plutonium-238 [wikipedia.org]

Anyway the reason congress keeps denying funding to try making more P-238 is they just want NASA to find a way of using P-239 instead. That will also solve the problem of there being tons of the stuff in storage we have no need for.

The only reason they use P-238 at present is because of it's shorter half-life and the fact that it only gives off alpha particles which are relatively easy to stop. I reckon it must be fairly easy to get power out of P-239, the only problem is that if it goes wrong it will go wrong in the most spectacular manner possible :)

Or...not? (1)

paiute (550198) | about a year and a half ago | (#41220877)

...who can say how productive plants are ultimately going to be on the moon, in gravity that is only one sixth that of earth?

Or unproductive. Plants are complex biological systems which evolved over millions of years in one g. The moon is not magic.

Re:Or...not? (0)

Anonymous Coward | about a year and a half ago | (#41220991)

" The moon is not magic."

Yes it is, for a type of geek called a Space Nutter. No leap of faith is too large, no sci-fi is too fantastical, no Space Age daydream too whimsical. The entire human species has to get off this "rock", to go on the other rocks that are far better than the Earth.

I'm not even close to kidding either.

Mirrors? (3, Funny)

cheros (223479) | about a year and a half ago | (#41220883)

Only 1/6th gravity, no atmosphere - why not use mirrors? You can afford some inefficiency, such cheap materials would mean you don't need to worry too much about replacement costs due to meteorite hits.

It doesn't always have to cost gazillions - I refer you to the Russian use of pencils.. :)

Re:Mirrors? (2)

Lumpy (12016) | about a year and a half ago | (#41220941)

"It doesn't always have to cost gazillions - I refer you to the Russian use of pencils.. :)"

Oh that thing they did not actually do and is just an internet fairy tale?

http://www.snopes.com/business/genius/spacepen.asp [snopes.com]

Re:Mirrors? (1)

wvmarle (1070040) | about a year and a half ago | (#41221017)

This urban legend well pre-dates the Internet (as in: the commonly available Internet for the masses, not the network as such). I know it since at least the early 90s. Possibly longer.

Re:Mirrors? (2)

Rogerborg (306625) | about a year and a half ago | (#41221073)

I love when wise guys link to that article without bothering to read it or to understand the significance.

Lead pencils were used on all Mercury and Gemini space flights and all Russian space flights prior to 1968

The lesson being that low tech worked just fine.

And if we're going to actually get out there and stay in space, then we need to be able to make do and get by. Apollo 13 was fixed with duct tape and a sock. The ISS is currently screwed because they can't get a single bolt to turn and are paralysed with indecision: we've taken everything up there except the right stuff.

Re:Mirrors? (0)

Anonymous Coward | about a year and a half ago | (#41221321)

The lesson is that people make shit us claiming that billions was spent on the pens. when in reality they were as cheap as a good pen on the ground.

AKA Just like all the republicans and their current round of making shit up.

Re:Mirrors? (2)

TubeSteak (669689) | about a year and a half ago | (#41221533)

The ISS is currently screwed because they can't get a single bolt to turn and are paralysed with indecision:

They stretched the space walk an extra hour and forty five minutes to try and fix the bolt.
Nothing they tried worked, so NASA told the astronauts to strap the box down and leave it for the next scheduled spacewalk.

I'm not sure how you took those facts and ended up at "paralysed with indecision."

No actually not (4, Insightful)

Sycraft-fu (314770) | about a year and a half ago | (#41221539)

Notice the reasons that NASA was interested in a pen: Pencils could break and cause a hazard, and additionally were susceptible to a fast burn in the oxygen rich environment.

Pencils worked. They didn't work "just fine" they were a hazard, but nobody has a better system, until the pressurized pen.

While high tech for its own sake can be a bad idea often there's good reasons for new technology. The old tech may work but the new tech works better, more efficient, more reliable, less dangerously, etc.

As a simple example you've probably used, take optical mice vs ball mice. Yes ball mice work, however they have numerous problems. Optical mice work better. They are less susceptible to dirt, easier to clean, track on more surfaces, work at all angles including upside down and so on. As an extension, newer ones are getting even better, they have greater precision, track on even more surfaces, and so on.

So if you want, you can heat your water in your low tech "works just fine" fire pit with wood and a metal bucket. I think I'll heat mine in my high tech sealed water heater that is very efficient, safe, and convenient, because it works better.

Re:Mirrors? (2)

Hentes (2461350) | about a year and a half ago | (#41221281)

The Russians did use pencils, but what the legend fails to mention that they could do that because they didn't use a pure oxygen athmosphere, unlike the Americans. Graphite in oxygen was a fire hazard for them.

I can easily Halve the space needed. (1)

Lumpy (12016) | about a year and a half ago | (#41220933)

In fact current hydroponic systems reduce that space needed by 1/4. If money was actually spent on research they could further reduce the space needed to process Co2 and generate O2 by using plant material.

And WHY use nuclear powered? we could easily put up solar farms. yes you have to deal with the face that the lunar days are 28 earth days but storage can deal with that. You dont have weather to contend with, so every day period will be a perfect charging period.

I personally think go big or go home, launch and install a 20MW nuclear power plant if they want to go nuclear.

Re:I can easily Halve the space needed. (1)

ravenlord_hun (2715033) | about a year and a half ago | (#41221023)

Solar farms would have serious issue with micro-meteorite impacts though. It's worse than on a space station or satellite even, because these will be unable to manuever, and impacts that hit the nearby surface will also have a good chance of damaging them. They'd only be a viable solution if they are constantly maintaned. That's not to say they'd be impractical; just not a perfect solution on their own - there'd need to be backup power in case some of the farms drop off-grid.

As for why use RTG and not a full-blown reactor, running a RTG is way more simple than a xMW nuclear power plant. It's easier to maintain - actually, it shouldn't need much maintenance at all - , it barely needs any active cooling system. (Actually, without an atmosphere to provide a nice medium to transfer heat to, how would a nuclear power plant work in space? Apart from using an obscenely big thermal radiator.) And I doubt there'd be need for 20MW power on a moonbase, unless they want to ship massive amounts of people there or operate some sort of complex machinery. That said, I'm no nuclear scientist, so I could be dead wrong there. :)

Re:I can easily Halve the space needed. (0)

Anonymous Coward | about a year and a half ago | (#41221071)

Radiated heat. Missed physics classes ?

Re:I can easily Halve the space needed. (1)

Lumpy (12016) | about a year and a half ago | (#41221307)

No, that radiated heat from the reactor is used to heat the facilities. DUH.

Re:I can easily Halve the space needed. (1)

ravenlord_hun (2715033) | about a year and a half ago | (#41221311)

Quote from above: Apart from using an obscenely big thermal radiator

It's amusing how can one make so snarky comments with such dismal reading comprehension skills. Of course made by an Anonymous Coward too.

Re:I can easily Halve the space needed. (1)

HungryHobo (1314109) | about a year and a half ago | (#41221217)

yes you have to deal with the face that the lunar days are 28 earth days but storage can deal with that.

You say that like it's nothing.

1: you piss away half your energy converting to battery and back again.

2: no it can't. try running an indoor grow house off batteries for a week solid. it's not a trivial task. you don't just need light but also heat.

you wave away massive problems. 2 weeks of darkness kills solar dead unless you want to ship many many many times the weight of a reactor up in the form of batteries.

What about livestock? (1)

Lumpy (12016) | about a year and a half ago | (#41220959)

WE all want Moon Goats... What about the moon goats?

Re:What about livestock? (0)

Anonymous Coward | about a year and a half ago | (#41221167)

The use of goats in space actually has been studied. There's one very important thing that you must know about them though - do not bring any male goats into space. If you need more than one generation of goats, use artificial fertilisation. A female goat signals that she is ready to mate by generating a smell that is absolutely horrible. You do not want that in an airtight system. You really really do not want that if you don't have filters that can deal with it.

These stories (0)

Anonymous Coward | about a year and a half ago | (#41220975)

Are why I read Slashdot daily.

lunar night? (1)

vipw (228) | about a year and a half ago | (#41220995)

There is no lunar night. There's a dark side and a light side, and occasionally an eclipse.

Re:lunar night? (0)

Anonymous Coward | about a year and a half ago | (#41221065)

I guess you forgot that the moon is tidally locked - whilst we always see the same side (with about +/- 5 degrees of libration) the sun lights up every part of the moon every 28 days.

Re:lunar night? (2)

vipw (228) | about a year and a half ago | (#41221101)

So now I must either admit that I'm stupid, or burn you at the stake for your blatant heliocentric viewpoints.

I'm stupid.

Re:lunar night? (0)

Anonymous Coward | about a year and a half ago | (#41221187)

Well, to be fair this was my first thought as well. I had understood that the moon did not rotate but it appears that it does have synchronous rotation. You can spend your whole life correcting things like this that you were only partially taught...

Re:lunar night? (0)

Anonymous Coward | about a year and a half ago | (#41221343)

Totally off-topic - sorry - you reminded me when you said "things like this that you were only partially taught",

This is an interesting read, I'm ashamed of how many things are on this list that I thought were gospel.

http://en.wikipedia.org/wiki/List_of_common_misconceptions [wikipedia.org]

Re:lunar night? (0)

Anonymous Coward | about a year and a half ago | (#41221103)

Who'd have thought a slashdotter with such a low id would be such an ignoramus LOL

Location, location, location! (0)

Anonymous Coward | about a year and a half ago | (#41221035)

On the Moon have the bases at the poles with a rotating solar collector to focus and direct the sunlight 24 hours a day except when the moon is eclipsed by the Earth.

Can't you just change the plant's (1)

kaspar_silas (1891448) | about a year and a half ago | (#41221083)

I would imagine it would be far far easier to breed (or use GM techniques) to make a crop plant that can deal with what is effectively a super short season than to attempt to light up the night. You could even store some of the daytime heat and smooth the "seasonal" temp transitions using a high heat capacity plastic mixed into the soil.

Given tundra based trees survive months with no usable light due to thick snow cover and natural summer annuals often only get light for growth for a few weeks a year this doesn't seem the biggest issue with moon farming.

Can't a machine make the food (0)

Anonymous Coward | about a year and a half ago | (#41221093)

Why do we need plants? Can't we just make machines that make food. Can't we make a machine more efficient than a plant?

Moon Nazis (1)

edxwelch (600979) | about a year and a half ago | (#41221213)

So, what about the moon nazis? They aren't going to be happy about colonists setting up nuclear farms on their turf.

Yes, the moon nazis. The ones that set up that secret base on the dark side just before end of WWII.

Re:Moon Nazis (1)

Coisiche (2000870) | about a year and a half ago | (#41221309)

The "it's on the dark side of the moon so it can never be seen" idea doesn't really hold up to much scrutiny. A few humans (some still alive) saw the dark side in the late 1960s/early 1970s and more recently the LRO is imaging the surface in a detail that even Apollo astronaut tracks can be seen as well as some of the discarded hardware (and I don't just mean what landed, some bits ended up there after being discarded from lunar orbit).

One could say "Well duh, the base is underground!" but then every single surface disturbance would have to have been obscured to return the surface to a pristine state because it's not like weather was going to do it. And knowing humans, even uber-efficient German ones, that just wouldn't happen.

Easy Solution (0)

Anonymous Coward | about a year and a half ago | (#41221261)

Easy solution- Legalize Pot if it's grown on the moon.

Crazy Alternative (0)

Anonymous Coward | about a year and a half ago | (#41221291)

What if we were to accept the fact that Earth is the only planet we're ever going to have and manage our resources accordingly?

Tap Slashdot expertise (0)

Anonymous Coward | about a year and a half ago | (#41221293)

There just *might* be some Slashdot readers who have experience growing plants - whatever kinds of plants those might be - in places where they are hidden from natural sunlight, using artificial lighting for photosynthesis.

Don't forget to post as AC via Tor.

Thanks!

The problem is power.... (3, Interesting)

Catmeat (20653) | about a year and a half ago | (#41221349)

This is all about the moon's 14-day, Lunar–night power famine. The solution is simply to use solar power satellites [wikipedia.org] sitting at one of the Earth-Moon Lagrangian points, where the solar collectors will be in perpetual sunlight. Perpetual power means always-on growing lights so the problem is solved without the need for RTGs, and their pretty horrible thermal inefficiency (not to mention the problem of where do you get all that Pu239 from).

The main problem with using solar power satellites for supplying power to the Earth (the huge cost of launching them into space) is neatly inverted in the Lunar context as, by placing a solar colony's power hardware in space, you have a large mass of hardware that doesn't have to be soft-landed on the moon, representing a substantial saving.

Farmers in the sky (1)

Bucc5062 (856482) | about a year and a half ago | (#41221389)

The 50 Sq meter comment bugs me. Its not like we are plowing the back 40 with mules. By now can't we think more 3d? if 50 sq meters would feed one human, how many humans would 1000 cubic meters feed (10x10x10 room)? A greenhouse dedicated to growing could have walls, even the ceiling used for growing. My imagination can think of many other problems, but in a low gravity environment space should not be one. If fact, why not have a module orbiting the Moon that is specific to growing food and just use gravity for the delivery...ah, just hit me, fuel for deorbit and landing would make it prohibative (rats).

I like the idea of Nuc power. We drive submarines and aircraft carriers with this power and if they can keep it safe and working 600 feet over the ocean, I think sitting on the moon would not be much bigger a problem (other then delivery). Fuel disposal would be much simplier (huge incenerator only 93M miles away), and I recall there is the building blocks for making fuel right there.

If NASA is looking for the right stuff to farm on the moon, I'm all in.

RTG is VERY costly (1)

Zdzicho00 (912806) | about a year and a half ago | (#41221391)

I think somewhere around $60M per piece, maybe even more given very limited availablity of plutonium-238. USA already ceased production of it::
http://www.spacepolitics.com/2011/09/11/senate-energy-bill-includes-no-pu-238-funding/ [spacepolitics.com]
PU-238 can only be bought from Russians (as it was done in case of Curiosity power source):
http://www.slate.com/articles/health_and_science/science/2012/08/mars_rover_curiosity_its_plutonium_power_comes_courtesy_of_soviet_nukes_.single.html [slate.com]
Hovewer RTG will be producing heat and 100-200 W of electricity for 100 years.

I would say something like this is needed:
http://pesn.com/2012/08/22/9602166_Existence_of_1200_C_E-Cat_Test_Report_Confirmed/ [pesn.com]

Nuclear powered lasers on sharks for space fishing (1)

turkeyfeathers (843622) | about a year and a half ago | (#41221673)

... way better idea!

Re:Nuclear powered lasers on sharks for space fish (0)

Anonymous Coward | about a year and a half ago | (#41221719)

Sharks aren't fish... they're a type of whale.

Problem with the opinion (1)

khallow (566160) | about a year and a half ago | (#41221685)

Current solar-powered battery storage technology isn't adequate to sustain artificial light sources for two weeks at the time.

This is simply wrong. Rechargeable batteries can easily hold a charge longer than two weeks. And once you have that, you have the ability to sustain light sources on battery power for two weeks.

Thus, the most practical solution is simply to use some sort of Radioisotope Thermoelectric Generator, not unlike the one powering the current Mars Science lab, to power the LEDs that will spur photosynthesis in lunar greenhouses.

No, it isn't. RTGs are limited by heat dissipation. Put enough isotope in one place and it heats up enough to melt. More and it'll eventually vaporize or perhaps even achieve criticality (such as the case with plutonium 238). A traditional nuclear plant scales better at high power levels.

So to get the scheme to work on a large scale, one needs a whole bunch of RTGs through the complex. That introduces all sorts of complexity issues.

Frankly, a better approach to me seems to be solar thermal with underground storage of heat. Heat up the fluid during the lunar day and draw down the heat during the lunar night.

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