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Developing New Materials With Space Science

Scientists at the European Space Agency are using techniques inspired by their experience with outer space to make new and better products here on Earth. Certain compounds and alloys which are not normally viable can be made in different ways once forces such as gravity are removed from the equation. From BBC News: "The near absence of gravity (microgravity) has a profound influence on the way molten metals come together to form intermetallics and 'standard' alloys. With no 'up' and 'down' in the space environment, a melt doesn't rise and sink as it would at the planet's surface and that means solidification can turn out very differently. 'Gravity induces a lot of segregation of the elements,' explains IMPRESS scientist Dr Guillaume Reinhart. 'For instance, tantalum and niobium are heavy atoms and in doing the solidification process on the ground, they will segregate in different places and produce a very heterogeneous material. If you do this in microgravity, you obtain a very homogenous material because you prevent separation; and you have a much more efficient material, mechanically.'"

62 comments

  1. Why use space? by Anonymous Coward · · Score: 0

    I guess making those materials by free drop in a mine shaft isn't as expensive or as cool.

    1. Re:Why use space? by MindStalker · · Score: 3, Insightful

      The time to heat, mold, cool a new metal could take hours, no practical way to setup an hour long freefall.

    2. Re:Why use space? by Anonymous Coward · · Score: 4, Informative

      Ignoring the deceleration problem at the bottom, with a 5 km shaft (which is not cheap to make) you only get 30 seconds of free fall to work with. And that's in a vacuum! In any shaft on earth, you are going to have air, which means you will hit terminal velocity at some point, which will ruin the effect.

      This duration of free fall is comparable to the Vomit Comet, which can produce brief periods of free fall without the ugly smashing part at the bottom of a mine shaft. :)

    3. Re:Why use space? by TheLink · · Score: 1

      Sure. But what if you keep rotating the mold as it cools down? Or do something similar?

      But yeah, people often don't want a homogeneous material, they want stuff like the material being different at the edges from the core. So maybe "weightless" environments might help (lots more control), but without real numbers - significant difference in alloy strength or other characteristics, it's just not very exciting to me.

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    4. Re:Why use space? by F�an�ro · · Score: 3, Interesting

      Terminal velocity can be overcome by generating a partial vacuum in the tower, and by accelerating the falling cabin downwards past terminal velocity, on some sort of rail system.

      I think there is one free-fall tower for scientific experiments that does both of these already but I do not remember where I read that.

      The short duration of freefall for any realistic height for a tower remains thought

    5. Re:Why use space? by Hojima · · Score: 2, Informative

      Actually, orbiting is considered free falling, and that can obviously last much longer than a few hours. That's one of the main reasons that newbie astronauts vomit in space, because even though it looks like they experience no sensation, they actually feel like they are falling 24/7 (an extremely nauseating event).

    6. Re:Why use space? by RobRyland · · Score: 1

      you are off by a factor of 2.
      you are correct that a 5km drop gets you ~30 seconds of freefall (0.5at^2). but you could start at the bottom of the shaft and launch up (with a brief high-g acceleration) and then be in freefall all the way up and all the way down, for ~60 seconds of uninterupted freefall. The high-g at lauch would be the same as the breaking g at the end of the trip.
      you could get 30 seconds of freefall with only 1.125 km worth of shaft.
      just a nitpick, but...
      -Rob

    7. Re:Why use space? by dotancohen · · Score: 2, Insightful

      You speak like a physicist, not an engineer. In theory, you are correct. In reality, how will you launch the material, such that it travels at exactly 0 degrees from vertical, at the required velocity? Solving for v in m*h*g=0.5*m*v^2 I get 150 m/s launch velocity. At perfect vertical. On a payload that contains a manufacturing process, probably including a molten metal. More than a kilometer below ground level.

      --
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    8. Re:Why use space? by drinkypoo · · Score: 1

      Terminal velocity can be overcome by generating a partial vacuum in the tower, and by accelerating the falling cabin downwards past terminal velocity, on some sort of rail system.

      You don't need vacuum. Terminal velocity is based on the maximum speed of a falling object due to drag. If it's not falling, but instead being pushed, then it's not subject to terminal velocity, just loss of energy due to drag, like your car... until you drive off a cliff anyway.

      --
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    9. Re:Why use space? by F�an�ro · · Score: 1

      Here are the guys that create a partial vacuum in their drop tower. I thought they also used some sort of rail system, but that might have been another tower.

    10. Re:Why use space? by BattleApple · · Score: 1
      These guys seem to have figured out how to do it..

      In the drop facility Fallturm Bremen University of Bremen in Bremen, a catapult can be used to throw the experiment upwards to prolong the weightlessness from 4.74 to nearly 10 seconds. Neglecting the physical space needed for the initial acceleration, this technique doubles the effective period of weightlessness.

      http://en.wikipedia.org/wiki/Drop_tower
    11. Re:Why use space? by dotancohen · · Score: 1

      h=y0+y*t+0.5*g*t^2=0+0+0.5*10*(10/2)^2=125m
      E=m*g*h=m*1250
      Thus, you've got 1250 J for every kilo in the Bremen facility.

      Your 1125m shaft from the previous post requires almost ten times the energy.

      --
      It is dangerous to be right when the government is wrong.
  2. IMPRESS? by Eudial · · Score: 0, Offtopic

    Maybe I'm getting old, but IMPRESS sounds a wee bit too close to IPCRESS for comfort.

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  3. Incentive for Commercial Space Exploration by cheesethegreat · · Score: 3, Insightful

    This is exactly what we need to jump-start serious commercial investment from companies like Dow Chemicals in space exploration. They'll never give more than token amounts to a project which is for the "betterment of mankind and improvement of human knowledge".

    But...if they think that they can make products superior to their competitors (or even better, products which are unique) then you can bet they'll be very interested in setting up orbital refineries and finding economical ways of doing it.

    This is the first really hopeful news about a continued human presence in space that I've heard in quite some time (Virgin's space gimmicks notwithstanding).

    1. Re:Incentive for Commercial Space Exploration by KGIII · · Score: 3, Insightful

      I think that, in the minds of your average person, the "conquest of space" was completed back in the late 1960's and now most view it as a drain on the budget and a waste of resources better used elsewhere. Unfortunately this mindset is also present in the c-levels that make such policy decisions.

      *sighs* Yet another case of chicken and the egg... If a company were to successfully profit from space, development in space, or research then most companies, such as your aforementioned Dow, would be all over the idea and attempting to exploit anything and everything. Alas, no one has done it and it seems that such is likely to stay true for a while as getting into space is damned expensive.

      Anyone care to justify that to the shareholders? Anyone think they'll have any luck making a case for it with the beancounters?

      --
      "So long and thanks for all the fish."
    2. Re:Incentive for Commercial Space Exploration by Tablizer · · Score: 1

      if they think that they can make products superior to their competitors ... they'll be very interested in setting up orbital refineries and finding economical ways of doing it.

      Hopefully they will finally make use of that money-sucking IIS...I mean ISS space station.

    3. Re:Incentive for Commercial Space Exploration by vandelais · · Score: 2, Interesting

      Exactly. Pure science will always have its backers, but if you can convince politicians by connecting the dots between pure science and applied science you can convince a few more to lead. Stuff like this is only an earmark or two away from tenability.

      Even if you can make a hypothesis that connects pure science to applied science ONLY IN THEORY, that can be the leash tug that results in real advancement.

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    4. Re:Incentive for Commercial Space Exploration by DiEx-15 · · Score: 1

      I concur. It is about time private companies start picking up the slack that NASA has. I am sure there are ways that companies can make their own methods and techniques to explore space. This is in addition to the money that can be made by advancing science and technology.

      What I feel is going on is that since there is no space race anymore, John and Susie Q Public have little interest in space anymore. Never mind the fact that one day we have to consider getting off of Earth. Space is a new frontier and I strongly feel nothing new is coming as long as NASA is the only pitcher on the mound and nobody else is wanting to try to compete.

    5. Re:Incentive for Commercial Space Exploration by GodfatherofSoul · · Score: 1

      What about the expense? It's still insanely expensive to push pounds into space and bring them back. Until national governments absorb more of the R&D to get us to the point of cheap space travel, Corporate America will not follow. Spare me the Ron Paul rhetoric. If Dow saw profit in it, they would have done so by now. This is not news. We've known this for decades.

      --
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    6. Re:Incentive for Commercial Space Exploration by Grishnakh · · Score: 1

      Sorry, I'm going to have to inject some Ron Paul rhetoric in here.

      National governments can't absorb the R&D for space missions when they're too busy spending all their money on foreign wars, and on keeping the oversized military stationed in well over 100 countries overseas. If we eliminated all that unnecessary expense, it'd probably be a lot easier to spend 1/10 of it on the space program, which would be a gigantic increase over its present budget.

      You may not like Ron Paul for some reason, but he's the ONLY candidate I've ever seen who talked sense about getting the US out of pointless foreign wars like Vietnam and Iraq, and getting our military out of the hundreds of other countries where it has bases established. The neocons certainly aren't interested in that, and the Democraps, while pandering to the anti-war crowds, don't ever actually do anything substantive on that front. If Hillary or Obama is elected this year, I predict that very little will change with our military and its overseas operations.

    7. Re:Incentive for Commercial Space Exploration by GodfatherofSoul · · Score: 1

      he's the ONLY candidate I've ever seen who talked sense about getting the US out of pointless foreign wars like Vietnam and Iraq

      Wow, I've suspected that conservatives live in a news bubble, but I didn't think it was that bad.

      --
      I swear to God...I swear to God! That is NOT how you treat your human!
  4. NASA used to talk about this by Animats · · Score: 4, Insightful

    Back when the Shuttle was called the "National Space Transportation System" and NASA was claiming that launch costs would come down, NASA used to talk about materials processing in space. That was a long time ago.

    The trouble with materials processing in space is that for small things, gravity is dominated by surface tension and other forces like Brownian motion. So biological processing in space never amounted to much. Some early Shuttle flights carried an electrophoresis apparatus designed for zero-G operation to make some kind of diabetes drug. But bioengineering went beyond that approach; today it's easier to engineer some bacterium to crank out whatever you need.

    For big objects, there would be some advantages (and many disadvantages) to working in zero G. Handling molten metal in zero G safely would be tough. One molten droplet could puncture anything we currently send into space. With gravity and in air, molten droplets don't travel very far and cool. In space, they can go a long way. Steel mills use floors of dirt or refractory brick in molten metal areas; concrete will blow up when its water content boils. Welding in space has been tried, but on a very small scale, and very nervously.

    Lift to orbit is far too expensive to justify flying heavy metal up there for casting and welding. This is one of those ideas that won't be feasible unless and until lift to orbit costs about what long distance air travel costs now.

    1. Re:NASA used to talk about this by tomtomtom777 · · Score: 1

      This is one of those ideas that won't be feasible unless and until lift to orbit costs about what long distance air travel costs now.

      It's feasible if the new material is worth more then its production and transportation costs. There might be very valuable use-cases, so your statement seems a bit to early in my opinion. It might be worth it to check it out.

    2. Re:NASA used to talk about this by Anonymous Coward · · Score: 0

      I could not agree more,

      However one very achievable way around this would be asteroid mining. While I don't know the make up of asteroids off the back of my hand, one would assume they are the material debris cast off during planetary construction right? So they should have some level of the same heavy elements we find on earth like the ones we are talking about here. For instance Tantalum.

      If orbital refineries were built that were capable of processing the valuable material out of an asteroid and then simply "dropping" the usable material to earth as a refined and unique micro-gravity-processed-product. If it's economical it would be a lot smarter then sending it up from the planet surface and then back down again.

    3. Re:NASA used to talk about this by Rinikusu · · Score: 1

      Asteroid mining/refining?

      --
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    4. Re:NASA used to talk about this by MattskEE · · Score: 1

      The problem with this is that asteroids are very spread apart in our solar system, moving quickly, and usually also far away. Just getting to asteroids with any sort of heavy equipment capable of processing and refining it into useful metal will require a ridiculous amount of fuel.

      Getting it back to earth also very tricky. The US has at great expense designed systems capable of bringing space shuttles and command modules safely from orbit to the ocean or ground. The problem is, these are all expensive and would require either parachutes, retrorockets, or the ability to glide like the shuttle. If it is just allowed to fall ballistically back to earth, a bunch of it will get vaporised, and a great deal of effort will need to be expended to reduce the probability of it landing in an ocean where it would immediately sink, or in a habited area.

      It's a nice idea, and it makes sense to do a more in depth study, but I think we are still a very long from that becoming viable.

    5. Re:NASA used to talk about this by soldeed · · Score: 3, Insightful

      I beg to disagree! The potential usefulness of novel vacuum cast alloys is incalculable. I just can't stand the attitude that we should not do a thing because of expense or difficulty. A REAL engineer rolls up his sleeves and figures it out! Who knows? Some material(s) yet to be invented, only possible to make in a vacuum may be the key to making a spacecraft efficient enough to bring down launch costs! Developing new technologies is always difficult and expensive, but you never learn how to do anything until you overcome the obstacles and DO it!!

    6. Re:NASA used to talk about this by soldeed · · Score: 1

      AHEM! When I say 'VACUUM" above of course I meant "ZERO GEE" Yeah, I know!

    7. Re:NASA used to talk about this by khallow · · Score: 1

      I just can't stand the attitude that we should not do a thing because of expense or difficulty.

      I can't stand the attitude that we should do something at ridiculous expense merely because we're too dumb to figure out if there's any payout to it or how we can do it for less. "Incalculable" doesn't mean that it'll have any value. As I see it, the only sane way to approach space development and exploration is to use those scarce resources in an effective manner. That means paying a lot of attention to expense and getting a good idea of possible payout. If we don't know enough then explore the space in a more cost effective manner, For example, the current environment is even with the ISS very expensive to run materials engineering experiments in space. It's better to probe first using modeling software or physical processes that give near approximations. For example, a two meter piece of vacuum alloy may be impossible to create on Earth, but a two micron piece isn't so. You can find out a lot without having to dump it all in a high cost environment first.

      Some material(s) yet to be invented, only possible to make in a vacuum may be the key to making a spacecraft efficient enough to bring down launch costs!

      And space fairies might use their magic wands to lower launch costs. Any sufficiently large improvement in materials science is going to effect everything, but we can't depend on them ahead of time. I'm sorry if that wasn't what you meant, but it seems to me a natural implication of your words.

    8. Re:NASA used to talk about this by pimpimpim · · Score: 1
      I would like to add to this: Sometimes you can already "learn" by making a careful analysis and perform a few preliminary test, find alternative ways and save a lot of money and time. As a scientist I sometimes talk to engineers who want to solve everything by "rolling up their sleeves" and DO: a gazillion of experiments just to avoid having to read the literature and look for causes of their problem. Because they end up thinking the cause is not their problem, their problem is their problem.

      Now I understand that sometimes this is the best way to go, e.g. when you want to optimize process parameters of a 100-parameter system and don't have too much time to halt the process. There are luckily theories on how to have a smart way to randomly change these parameters and find the optimum. But if you want to create smart materials, you really need to put your smarts in it before doing anything.

      --
      molmod.com - computing tips from a molecular modeling
  5. Hey yeah! by Corpuscavernosa · · Score: 3, Funny

    That's where that "NASA approved" memory foam came from!

    --
    We figured out a long time ago that it's easier to elect seven judges than to elect 132 legislators.
  6. At what $$$ by Anonymous Coward · · Score: 0

    How much to launch a kilo of generic mass into orbit ? At that base cost + manufacture it will cost a fortune for these space materials

    1. Re:At what $$$ by MindStalker · · Score: 1

      Mining of asteroids and the moon will have to be developed obviously.

    2. Re:At what $$$ by GerardAtJob · · Score: 1

      Time to prepare for Apophis and dig it when it'll come close enough!

      --
      I can't call that English ;-)
  7. One step closer... by Ihmhi · · Score: 0, Offtopic

    ...to Gundanium, one step closer to Gundams.

    1. Re:One step closer... by NoobixCube · · Score: 1

      Everyone loves the overpowered monstrous Gundams, but there's something in me that likes the simpler Zakus. I also like the RK-92 Savage from Full Metal Panic. There's just something about clunky, mass-produced military technology.

      --
      Admit it. You post strawman arguments as AC so you get modded Insightful for refuting them, rather than Troll
    2. Re:One step closer... by Guppy · · Score: 1

      ...to Gundanium, one step closer to Gundams. I hear the Japanese Department of Agriculture is in charge of that project.

  8. The problem with corporations by Bragador · · Score: 3, Interesting

    Scientists at the European Space Agency are using techniques inspired by their experience with outer space.

    And this is why companies should understand that science projects that are for the betterment of mankind and for the improvement of human knowledge are long term investments.

    The problem is that the goal of corporations is to make a lot of profit in the short term. Rare are the corporations that are planning their growth in the long term. They plan for the coming years, not the coming 25 years.

    After all, where could useless theoritical research from imbeciles that live in their heads like James Clerk Maxwell possibly lead us? Surely if you don't see an application at the time, the research is a waste of time...

  9. Single Crystal Superalloys? by mebollocks · · Score: 2, Interesting

    Haven't single crystal superalloy tech already solved the problems caused by gravity and metallurgy? http://en.wikipedia.org/wiki/Superalloy I don't know, just asking...

    1. Re:Single Crystal Superalloys? by pohl · · Score: 1

      Doesn't the answer to that question depend on exactly what properties one would like the resulting material to have?

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    2. Re:Single Crystal Superalloys? by mebollocks · · Score: 1
      Well... yes. But the context (even the article summary) gives us that answer. The desired properties are heterogenity. By its nature a single crystal's elements are homogenously spread.

      'For instance, tantalum and niobium are heavy atoms and in doing the solidification process on the ground, they will segregate in different places and produce a very heterogeneous material. If you do this in microgravity, you obtain a very homogenous material because you prevent separation; and you have a much more efficient material, mechanically.'
    3. Re:Single Crystal Superalloys? by mebollocks · · Score: 2, Interesting

      Oops, I mean "The desired properties are homogeneity."

    4. Re:Single Crystal Superalloys? by pohl · · Score: 1

      Yes, the summary did give that one property (homogeneity). Aren't there dozens of other properties that might be relevant in deciding whether or not the problem is 'solved', though? Certainly I couldn't take any old homogeneous substance and make an awesome turbofan blade out of it.

      --

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    5. Re:Single Crystal Superalloys? by pohl · · Score: 1

      I guess what I'm saying is that the point of materials science research like this is often to discover new materials with new sets of properties. I don't think they're aiming right at exactly what single crystal superalloy tech can do already. I think they're asking "what cool materials can we make this way?"

      --

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  10. I really hate it when people mess up basic physics by weedenbc · · Score: 0, Offtopic
    Quote: "The near absence of gravity (microgravity)"

    Hate to break it to people but there is gravity in space. Otherwise, what keeps the satellites and Moon in orbit? In fact, at the altitude the space station orbits, the Earth's gravity is about 88.9% as strong as it on the Earth's surface.

    One of the biggest mistakes in the history of science was the term "zero-gee" which people assumed meant "zero-gravity" when in fact it means "zero force due to the acceleration from gravity". A "gee" is the amount of force gravity exerts at sea level.

    Microgravity doesn't mean that gravity is 10^-6 what it is on Earth - it means that the force resulting on an object due to gravity is 1 million times less than what it is on Earth, and thus you get all the nice effects mentioned in the article.

    --

    "Trying is only the first step towards failure." - Homer
  11. Interesting, very interesting...Answer me this! by Anonymous Coward · · Score: 0

    Certain compounds and alloys which are not normally viable can be made in different ways once forces such as gravity are removed from the equation
    What other forces are being implied here?
    1. Re:Interesting, very interesting...Answer me this! by MindStalker · · Score: 1

      Earths magnetic field? Centerfugal (spelling?)

  12. Space Science!!! by Anonymous Coward · · Score: 0, Funny

    "What you see before you is the OmegaBlender, created entirely through the ingenious use of SCIENCE!!!"
    "What you see before you is the OmegaBlender, created entirely through the ingenious use of SPACE SCIENCE!!!"


    I'd just like to say that developing something using Space Science sounds completely and utterly awesome.

  13. Do it on earth with freefall? by Dwedit · · Score: 1

    Can you get a similar gravity situation on Earth by having the chemical reactions happen in free fall?

    1. Re:Do it on earth with freefall? by aXis100 · · Score: 1

      If you RTA, it says that's how they currently do it - sounding rockets, parabolic flights and drop towers.

  14. Re:I really hate it when people mess up basic phys by Twisted64 · · Score: 1

    A "gee" is the amount of force gravity exerts at sea level.
    Low tide, high tide, or in between?
    --
    Consciousness is a myth. Trust me.
  15. Its been done by PPH · · Score: 1

    Why do you think they keep cement trucks' mixers rotaing slowly during transportation?

    --
    Have gnu, will travel.
  16. Near absence of gravity... by the_other_chewey · · Score: 2, Informative

    TFA: The near absence of gravity (microgravity) ...

    JFTR: At 400km above ground (the ISS's orbit), the gravitational acceleration
    the Earth exerts is still about 88% of the acceleration on the ground.

    It is a very common misconception that gravity somehow instantly vanishes as you
    arrive in space. It isn't so - in fact, gravity is crucial for that weightlessness in orbit.

  17. I believe the term is "boondoggle" by doom · · Score: 1

    I've always liked the idea of microgravity materials processes, but with launch costs the way they are, there isn't any way you're going to manufacture some novel material in space for use on the ground. There remains a lot of "interest" in microgravity processing in space, but largely it's because there's nothing else you can work on to justify having a space station.

    One caveat that there might be some scientific value to cranking out samples in orbit (e.g. creating samples large enough to do x-ray crystallography on, and thus learn something about the structure of the exotic materials). On the simplest level, I would expect that if you crystallized a material in space that looked like it had some industrial use, that would provide the motivation to figure out how to manufacture it using ground-based techniques.

    This is another application of the rule-of-thumb that while launch costs are high, the only thing that's practical to ship is something that doesn't weigh anything: information (think communication satellites).

    I would still bet that the next big step in space industrialization would be the solar power satellite. After that we can start working on mining the moon, the asteroids, and maybe finally reduce earth-to-LEO launch costs, one way or another.

    But that would take an actual commitment to a real project... so for the forseeable future, we'll continue to see lots of make-work-in-space like this.

  18. How does gravtiy actually matter? by Steve+Hamlin · · Score: 1

    I think I see your point - it might be just a semantic one, but an interesting point anyway.

    True, the gravitation attraction of the earth still exists in orbit. In fact, it is what keeps the fast-moving ISS from flying off into space, because gravity keeps pulling the sideways-moving ISS down towards the Earth's center. This constant falling-but-never-landing state is called orbit.

    But can anyone please explain how this gravitation system affects experiments onboard the ISS? Common sense seems to indicate that from the ISS's frame of reference, there is no effective gravity. Not that it doesn't exist, but just that it doesn't matter.

    But is that really true? Would an experiment on the ISS in orbit around Earth, result in the same findings as the same experiment carried out in deep, non-galactic space, far way from large masses and stationary to distance reference objects? Although the only real difference is that the second frame of reference is just much larger than the first, as both still exist within the large structures of the universe which are whizzing around an inflationary space-time bubble.

    Even in orbit/'weightlessness', there is still the large mass of the nearby Earth. Does the presence of this large mass, around which the experiment is orbiting, have actual effects on the experiment? Is it just that it is such a small effect to be insignificant vs. sea-based-experiments? (But parent's calculation of relative strength of the gravitation attraction at 400km high vs. sea level = 88% might be relevant).

    Or it is entirely about the POV from inside the frame of reference of the experiment?

    1. Re:How does gravtiy actually matter? by mollymoo · · Score: 1

      Orbit isn't the same as no gravity, but the difference is usually small enough to ignore. Any mass warps the spacetime around it, so there is a difference between orbit (freefall) and zero gravity (which is what you'd get a long, long way from anything). As one example, according to General Relativity, your proximity to a large mass affects the rate of the passage time. The clocks on GPS satellites are set to tick faster than ground-based clocks, so that when in orbit the clocks on the satellites appear to tick at the same rate as those on the ground. GPS is a fairly extreme example (calculating the distance, accurate to a few metres, of several objects 15 000 miles away in different directions, traveling on curved paths at 10 000 mph) and relativistic effects can be ignored for most applications. I very much doubt they'd be relevant for making alloys in orbit.

      --
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  19. Old tech by fiannaFailMan · · Score: 1

    IIRC, lead shots were made by dropping molten lead down a tall chimney-like structure, they'd be cool enough to stay solid by the time they got to the bottom. Know how a raindrop is a sphere? Same principle.

    --
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