Take a ball of glass or polycarbonate, say 3 inches in diameter with a void about an inch across in the centre, and drill a fine, tapered hole into it so as to access the void.
Then take the ball into space and leave it there for a few months. Before bringing it back to Earth, put a tight- fitting tapered plug into the hole then return to Earth with it.
Atmospheric pressure should push the plug into the hole very tightly indeed, leaving a near-perfect vacuum inside the ball.
Sell balls that contain nothing to wealthy collectors of such curios.
Of course, if you were to take the plug out then the ball would be empty, rather than containing nothing.-- infidel, Oct 21 2011 I thought this looked a bit familiar. Space_20for_20sale [2 fries shy of a happy meal, Oct 21 2011] Yours is really out-of-this-world compared with Rare Earth Rare_20Earth [swimswim, Oct 21 2011] Vacuum Dirigible Service Tech Wanted_3a_20Vacuum_...le_20Service_20Tech [sqeaketh the wheel, Oct 25 2011] The same thing but not for sale http://www.foxnews....pture-space-bottle/You don't deserve extra points for tapered holes [mylodon, Oct 28 2011] Genuine space nothing! Don't accept inferior artificial vacuums manufactured at ground level!-- pocmloc, Oct 21 2011 You could probably sell small Balls of Nothing™ (made with an impermeable, soluble exterior shell) as a fad diet aid.-- hippo, Oct 21 2011 Filled with empty calories, [hippo]?-- infidel, Oct 21 2011 Gottfried Leibniz ping pong balls.-- skinflaps, Oct 21 2011 You'd better fit a nothing filter in there, or it might get filled with space dust.-- swimswim, Oct 21 2011 [ ]-- theleopard, Oct 21 2011 How much are you charging for that, [leopard]?-- swimswim, Oct 21 2011 The opposite of nothing.-- theleopard, Oct 21 2011 [+]
(in other words)-- theleopard, Oct 21 2011 I'd buy some. I could use some more space in the living room.-- RayfordSteele, Oct 21 2011 An idea about balls full of vacuum Made [bigsleep] mistakenly assume That writing in versewould not be perversewhen really it's a foretaste of doom-- hippo, Oct 21 2011 //when really it's a foretaste of doom//
It could be disastrous if these became extremely popular and they all "inhaled" a little bit of atmosphere at roughly the same time... everyone on Earth might asphyxiate.-- infidel, Oct 21 2011 [+] //and they all "inhaled" a little bit of atmosphere// Much sooner than that. Think of all the air that would have been removed from the Earth in the course of manufacturing the things.
[infidel]'s blown their cover: clearly an extraterrestrial engaged in atmosphere-smuggling.-- mouseposture, Oct 21 2011 False advertising: the ball of "nothing" contains lots of vacuum energy.-- DIYMatt, Oct 22 2011 Is this part of some strange scheme to bring space to us, a bit at a time?
Smaller nations could buy these one by one and eventually merge them into one big piece of space and insert their satellite into it, saving the launch costs.....erm...hang on...-- not_morrison_rm, Oct 22 2011 It won't be long before there's a Chinese copy: "Prove there's not a vacuum inside and we'll refund your money"-- Ling, Oct 22 2011 That's easily proven, if you can get the ball's density.-- RayfordSteele, Oct 22 2011 It's rather like the barometer/height-of-tower problem. How many different ways could you prove no vacuum inside, without removing the cork. Computerized tomography is obvious. (Does it count as penetration? Bearing in mind that natural electromagnetic radiation is passing through the glass constantly? Amend this one to "tomography + lawyers".) Mechanically oscillate it, while measuring reactive force, and demonstrate "sloshing" of internal gas, or rotate it, decelerate sharply, and demonstrate that gas inside continues rotating, transfering angular momentum to the outer shell, which then warms by friction? Suborn an employee of the manufacturer? Drill a hole through the cork? (Thereby evading the "penetrate the glass" criterion.) Demand ISO 9000 certification?-- mouseposture, Oct 22 2011 Hit it with a finely-tuned (i.e. narrow) ultrasound scanner; a vacuum will show up as a 'blank spot'. If there's air inside, there will be a return from the far interior wall.-- Alterother, Oct 22 2011 How about a container design with convex dimples that will only turn concave if the capsule contains a hard vacuum. Then you'd only need certification of authenticity from a reputable manufacturer to guarantee the contents... or the nontents as it were.-- 2 fries shy of a happy meal, Oct 22 2011 // reputable manufacturer //
A company is only as reputable as their bottom line allows. Independent testing is a necessity.
Even on novelty items.-- Alterother, Oct 22 2011 //How many different ways could you prove no vacuum inside, without removing the cork.// If the container was clear glass you could use spectrophotometry.-- DIYMatt, Oct 22 2011 I was just about to suggest that these glass balls be blown in space for a more permanant containment of nothing.... then I realized I'd sound like an idiot.-- MikeD, Oct 23 2011 Apart from the 'blown' part, which I took in the figurative sense anyway, you're actually on the mark; a vacuum environment is an excellent place to form glass structures. Theoretically, glass made in space could be as hard as steel, or more so.-- Alterother, Oct 23 2011 //you're actually on the mark//
Ah. I guess my brilliance has surpassed even me.
[2fries], your idea albiet the exact same product, doesn't have a see through container. If I spend a lot of money on nothing, I want to *see for my self* that something is not in there.-- MikeD, Oct 23 2011 That's why I said 'space' the second time. As per usual, I could have been more clear.-- Alterother, Oct 24 2011 Sorry, but I won't be volunteering to blow your balls, glass or otherwise, in space or anywhere else.-- infidel, Oct 24 2011 Pff, like I'd ask you to. T.G.F.J. has exclusive access as far as ball-blowing is concerned.-- Alterother, Oct 24 2011 Trans-Gender [FarmerJohn]??!-- hippo, Oct 24 2011 //I won't be volunteering to blow your balls, glass or otherwise, in space or anywhere else//
<HalfBaker Seuss?>
I will not blow your balls in zero-G I will not blow them, don't you see? I will not blow them on a shuttle. Not one single crystal bubble! I will not blow your balls in space. I will not blow them any place!
<HBS?>-- MikeD, Oct 24 2011 // Trans-Gender [FarmerJohn]??! //
No, sorry. The Good Fairy Jenny, who is [The Alterother]'s wife, at least until the hallucinogens wear off and she realizes what she's married to.-- Alterother, Oct 24 2011 Sweet! It worked!
Thanks [21]. I'm about to amend all of my limericks.-- MikeD, Oct 24 2011 Such a vacuum packaging procedure may be useful for the professional Vacuum Dirigible Service Tech. {link}-- sqeaketh the wheel, Oct 25 2011 Down in my office, on top of my desk, Is a small crystal ball that is empty, or less, See, the ball's been to space, and filled with the same, So the contents inside are a stuff with no name, For anything inside was surely leaked out, When the ball was opened in space and the air got sucked out. Before the ball was resealed and stowed in a box, Then delivered to Earth with some little green men and some rocks. Now it sits on my desk and mocks me at night, For the only thing in it is the ghost of starlight.-- infidel, Oct 26 2011 I wouldn't be so sure of that [21 Quest]. I was aiming for Theodore Geisel, I must admit.-- infidel, Oct 26 2011 Um, a glass vessel full of vacuum is a very dangerous thing to break. Old TV picture tubes used to be disposal hazards. The air pressure sends all the glass thudding inward, and it bounces back out.
Which brings up a test for vacuum: Buy two, break one.-- baconbrain, Oct 26 2011 //"Prove there's not a vacuum inside and we'll refund your money"//
Wouldn't a glass-ball containing a vaccum simply weigh less than a glass-ball containing some air?
Looking at it from another angle, shouldn't a full compressed-air cannister weigh more than the same compressed-air cannister once it's empty?-- zen_tom, Oct 26 2011 Yes [ZT] but you would have to empty the vacuum out of the ball , and then re-weigh it when it was empty.-- pocmloc, Oct 26 2011 You could buy two balls, break one, and then measure the weight of them both. If they weigh the same, then the remaining one is faulty.-- zen_tom, Oct 26 2011 That just proves that there are manufacturing tolerances.-- Ling, Oct 26 2011 Yes, my point exactly. You have to test the same ball twice, once before and once after breaking it.-- pocmloc, Oct 26 2011 But that's not going to prove it to the imaginary Chinese company. You are going to show them a broken ball and say it doesn't have a vacuum in it...or if you do it (your destructive test) in front of them, they can deny the results to any third party.
The test needs to be repeatable (non destructive) and portable.-- Ling, Oct 26 2011 Test it by using the fresh-egg test. Give the thing a spin, stop it for a moment, and see if it tries to start back up again.
You'd need to make the test more sensitive, of course, as there would only be air inside a fake. A simple motorized testing rig should be portable, if expensive.
[Later: Whoopsy. [mouseposture] suggested that up there a ways.]-- baconbrain, Oct 26 2011 Surely some sort of chromotography or spectromographic test would suffice?-- RayfordSteele, Oct 26 2011 If it's portable.-- baconbrain, Oct 26 2011 If I may reiterate: ultrasound! My dad has a very nice scanner that should do the trick, and a slightly less fancy one that is indeed portable. It's in my workshop right now; he brought it over to use as a stud-finder the other day. That's what made me think of it in the first place.-- Alterother, Oct 26 2011 That was inevitable. At least it was over with quickly.-- Alterother, Oct 26 2011 //ultrasound!// That will work, but not in the way you describe (if I understand you correctly). If the sphere's filled with gas, you'll see an image of the central, gas-filled void. If it's vacuum-filled you'll see no image at all, since the sound waves won't be transmitted through the center (hence not reflected off the far wall).
Actually, sound waves'll presumably be transmitted through the glass around the circumference, and set up complicated interference patterns -- hard to say what it would look like, but presumably nothing like an image of the central void.
On the third hand, maybe that effect will dominate even if the sphere's gas-filled (if the glass transmits ultrasound much better than the air. In which case, ultrasound wouldn't work as a way of disproving vacuum.-- mouseposture, Oct 26 2011 // If it's vacuum-filled you'll see no image at all, since the sound waves won't be transmitted through the center (hence not reflected off the far wall). //
That's exactly how I was trying to describe it when I wrote:
// Hit it with a finely-tuned (i.e. narrow) ultrasound scanner; a vacuum will show up as a 'blank spot'. If there's air inside, there will be a return from the far interior wall. //
I was thinking about throwing on some PPE and experimenting with some old vacuum-tubes I have, but I didn't know if they'd blow up or otherwise pose a risk of damaging my dad's equipment.-- Alterother, Oct 26 2011 It is easier to ask forgiveness than permission. But don't tell him I said that.
(Maybe you could get a goat, or something, to swallow a vacuum tube?)-- mouseposture, Oct 26 2011 But then we're risking damage to the goat as well. I have no idea what would happen if you passed an ultrasound scanner over a vacuum tube, but I can envision plenty of bad things that _might_ happen.-- Alterother, Oct 27 2011 balls of yet known-- wjt, Oct 31 2011 random, halfbakery