Space Glass
Posted on: October 3, 2010 - 5:52pm
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Space Glass
You make glass by mixing together some materials like sand, limestone and soda, heat them above 2000o F, then cool the incandescent liquid carefully so that crystals cannot form.
Craftsmen on Earth have followed this basic recipe for millennia. It works.
But it works even better in space.
In microgravity, though, you don't need a container. In Day's initial experiments, the melt--a molten droplet about 1/4 inch in diameter--was held in place inside a hot furnace simply by the pressure of sound waves emitted by an acoustic levitator.
Containerless processing produces a better glass.
To his surprise, though, the glass was of even higher quality than theory had predicted.
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Welcome back dude. I thought that possibly you had stopped posting for whatever reason.
Anyway, on the scientific level, you will need something that contains the glass. Simply put, liquids just are not viable in space without something that confines them in some way.
It could be the sound waves that you have in mind (although sound requires stuff that sound can travel through). It could be some form of magnetic confinement like the various Tokamak fusion reactors use. It could even be something that we have yet to imagine. Even so, there must be a way for the liquid to stay in one place.
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It's been already accomplished. It's proven.
--->
Glass made in space is better than glass made on earth.
It's better than moon-made glass
It's better than Mars-made glass.
This spells o-p-p-o-r-t-u-n-i-t-y for business and users of glass products (ie. Astronomers).
Dude, I am an astronomer.
I own a 120mm refractor that comes out to play at every chance. I routinely book time on 22 inch maksutov.
Let me give you a clue. The changing blue/white color bar in my sig is the current astronomical weather for my location. You can ask the owner of this forum but it has been there for many months.
I am a member of the Fairfelid County Astronomical Society.
I am a member of the American Association of Variable Star Observers.
I am a member of the Sidewalk Astronomer's Club.
Now, you will provide the exact location of the glass factory on Mars. If you can't do that much, then you will link to the web site for the experiment that made glass on Mars.
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Holy crap, accoustic levitation! Never heard of it before.
The melt--a molten droplet about 1/4 inch in diameter--was held in place inside a hot furnace simply by the pressure of sound waves emitted by an acoustic levitator.
Containerless processing produces a better glass.
To his surprise, though, the glass was of even higher quality than theory had predicted.
The window glass that we're so familiar with is made mostly of silica--a compound of silicon and oxygen. It's essentially melted sand.
But in theory, a melt of any chemical composition can produce a glass as long as the melt can be cooled quickly enough that the atoms don't have time to hook themselves up into patterns, or crystals.
In Earth-orbit, it turns out, these molten liquids don't crystallize as easily as they do on Earth. It's easier for glass to form. So not only can you make glass that's less contaminated, you can also form it from a wider variety of melts.
Glass made from other chemical compositions offers a panoply of unexpected properties. "Bioactive glasses" can be used to repair human bones. These glasses eventually dissolve when their work is done.
Right: Steel balls bounce on flat plates of titanium alloy, metallic glass, and stainless steel. The ball bouncing on metallic glass keep going for a remarkably long time. [more]
Also intriguing to space researchers is fluoride glass. A blend of zirconium, barium, lanthanum, sodium and aluminum, this type of glass (also known as "ZBLAN"
is a hundred times more transparent than silica-based glass. It would be exceptional for fiber optics.
A fluoride fiber would be so transparent, says Day, that light shone into one end, say, in New York City, could be seen at the other end as far away as Paris. With silicon glass fibers, the light signal degrades along the way.
Unfortunately, fluoride glass fibers are very difficult to produce on Earth. The melts tend to crystallize before glass can form.
Below: The surfaces of ZBLAN fibers formed in near-weightlessness (upper panel) and in normal Earth-gravity (lower panel). [more]
In melts that are more fluid, like those stirred by gravity, the atoms move rapidly, so they can get into geometric arrangements more quickly. In thicker, more viscous melts, the atoms move more slowly. It's harder for regular patterns to form. It's more likely that the melt will produce a glass.
In microgravity, Day believes, melts may be more viscous than they are on Earth.
While this theory has not yet been confirmed, some experimental results suggest that it is correct. NASA researcher Dennis Tucker worked with fluoride melts on the KC-135, a plane that provides short bursts of near zero-gravity interspersed with periods of high gravity.
"He did some glass-melting experiments, trying to pull thin fibers out of melts," recounts Day. "During the low-gravity portion of the plane's flight, when g was almost zero, the fibers came out with no trouble. But during the double-gravity portion of the plane's flight, the fiber that he was pulling totally crystallized."
That result, says Day, could be explained by shear thinning. "A melt in low gravity doesn't experience much shear. But as you increase g, there'll be more and more movement in the melt." Shear stresses increase. The effective viscosity of the melt decreases. Crystallization becomes more likely.
Day is currently planning his next experiment in space--onboard the International Space Station--which he hopes will confirm his ideas. He'll be melting and cooling identical glass samples in the same way on Earth and in microgravity. Then he'll count the number of crystals that appear in each sample. If shear-thinning exists, he says, there will be fewer crystals in the space-melted samples than in the ones produced on Earth.
Eventually, Day hopes to take these lessons learned from space and apply them to glass production on the ground. Metallic glasses. Bioactive glasses. Super-clear fiber optics. The possible applications go on and on.... which makes the value of this research crystal clear.
http://science.nasa.gov/science-news/science-at-nasa/2003/14apr_zeroglass/
more informationNASA's Office of Biological and Physical Research (OBPR) supports studies like Day's for the benefit of humans in space and on Earth
The "Glass Flows" Myth (Glassnotes.com) --learn more about the basics of glass.
ZBLAN continues to show promise (Science@NASA) Thin fibers of an exotic glass called ZBLAN are clearer when made in near weightlessness than on Earth under gravity's effects. [more]
Delbert E. Day -- (University of Missouri) home page
Fighting Cancer with Radioactive Glass Microspheres (National Engineers Week) Tiny glass spheres are proving an effective way of safely delivering large doses of radiation to cancerous tumors -- researchers see multiple medical possibilities
The Bare Bones of Bioactive Glass (Microgravity News) researchers are learning how to use glass beads to improve bone growth.
Microgravity Fiber-Pulling Apparatus (NASA) Thber-processing method provides a way to produce optical fiber composed of glass systems in low gravity.
Materials Science Overview - Metals and Alloys (Science@NASA)
Sounds hot...big, long, wide telescopes with all that silky smooth glass...
Everything makes more sense now that I've stopped believing.
I bet the astronauts did it with their minds.
Everything makes more sense now that I've stopped believing.
Well, I was also looking at a 200 mm Dobsonian. Those are way fucking cool too. However, when the time came to whip out the plastic, there was an $800 refractor on ebay for $300. About the same as the dob would have cost.
Anyway, most of us have several telescopes and I can still get the dob later on. That and my two older scopes are still around for parts. I have it in mind at some point to get a decent Maksutov to go on an old mount for a 114 Newtonian. Probably about a 90 to 120 mm optical tube. That will be pretty cheap and rather more portable than the others.
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Glass made in space is better than glass made on planets and moons because you don't need a container in zero-G.
This means better optical instruments.
Better lenses for telescopes. You get better night vision goggles, better rifle scopes, better robotics, better remote sensors, spectroscopy, infra-red, etc, etc.
The most accurate measuring devices are essential to get the very best science possible.
Cygo,
I am a physicist, and with all my due respect to your sci-posts, I should tell you that it is NOT glass quality that limits the optical resolution of telescopes on Earth. I think that Answers in Gen. may add sothing to this.
When you go shopping for a car to get you from home to work and back, would you buy a Ferrari? It is a BETTER car, so why not?
Also, molten metals can be levitated in vacuum on Earth.
Also, when you say that crystals in glass are bad-bad-bad, you are probably talking about some specific applications of glass (like cheap window class), because in many other optics applications quartz and sapphire are the materials of choice.
My quess is that the market for space-made glass will be VERY limited.
The only application in optics that I can foresee is a huge telescope lens made in space for a telescope that will be in space.
Also, this is wrong. 2000 Fahrenheits is not enough to melt sand/glass/etc. Perhaps, you need 2000 Celcius.
Many nice materials like SiC and BN are stable and inert at such high temperature.
All this idea with space glass, looks to me as someone makes up a problem for the only purpose to have a problem to solve.
OK dude, I still want to know the secret location of the glass factory on Mars. You have claimed to have that information. Spill it dude.
That being said, yes, it is true that there are things that can be made in free fall (you might call it zero G but the engineering term is free fall) that can't be made otherwise. The opposite is also true.
Speaking of glass do you happen to know why glass is the standard flat surface? Gravity is the answer.
Glass goes from fully liquid to the term “below the glass transition temperature” over the range where tin is a liquid. Glass factories make their product by floating in on molten tin. Tin at any temperature is fairly heavy and thus make a good base for stuff being flat.
Because of this, the flattest possible surface that can be used for polishing is a sheet of glass.
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Glass as art. Imagine the pine scent and cool crisp air - breathe.
Imagination is certainly required.
My source on this glass thingie:
http://science.nasa.gov/science-news/science-at-nasa/2003/14apr_zeroglass/
And related:
NASA's Office of Biological and Physical Research (OBPR) supports studies like Day's for the benefit of humans in space and on Earth
The "Glass Flows" Myth (Glassnotes.com) --learn more about the basics of glass.
ZBLAN continues to show promise (Science@NASA) Thin fibers of an exotic glass called ZBLAN are clearer when made in near weightlessness than on Earth under gravity's effects. [more]
Delbert E. Day -- (University of Missouri) home page
Fighting Cancer with Radioactive Glass Microspheres (National Engineers Week) Tiny glass spheres are proving an effective way of safely delivering large doses of radiation to cancerous tumors -- researchers see multiple medical possibilities
The Bare Bones of Bioactive Glass (Microgravity News) researchers are learning how to use glass beads to improve bone growth.
Microgravity Fiber-Pulling Apparatus (NASA) Thber-processing method provides a way to produce optical fiber composed of glass systems in low gravity.
Materials Science Overview - Metals and Alloys (Science@NASA)
The market for good glass is HUGE.
Cygo,
According to your numerous references, the market for good space glass is limited to the lab of Prof. Day. I am sure he was interested in this to continue getting funding from NASA.
Agreed.
Dude, I was in engineering school and computer science before I switched to physics.
I am not going to bother with that crap fest of links.
Give me one single link that clearly states that humans have built a glass factory on Mars.
You said that it exists. Prove it.
Exactly one single link, not a forest of crap links. Pick the one that makes your case and provide that single link.
Either that or admit that you are full of shit.
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I think that unbound imagination is common for both religion and pseudo-science.
In this case, science is probably valid, but its interpretaion is ready to fly to Mars.
because Saturn rocks.
Craftsmen on Earth have followed this basic recipe for millennia. It works. "Now we know it works even better in space," says glass and ceramics expert Delbert Day, who has been experimenting with glass melts on space shuttles over the past twenty years. Day is the Curators' Professor Emeritus of Ceramic Engineering at the University of Missouri-Rolla.Going into those first experiments, he says, he expected to end up with a purer glass. That's because on Earth, the melts--the molten liquid from which glass is formed--must be held in some kind of container. That's a problem. "At high temperatures," says Day, "these glass melts are very corrosive toward any known container." As the melt attacks and dissolves the crucible, the melt--and thus the glass--becomes contaminated.