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Cymatic Solar Beam
This one just popped into my head a few seconds ago so your guess may well be better than mine as to whether this would work. | |
A very large parabolic dish will focus sunlight into a point too hot to be collimated into a beam using current means as any lens will be vaporized, but...
...what if the reflector itself could create a series of focal lines or rings to keep heat below temperatures that will melt a glass lens?
I
am picturing a spinning pool of mercury. Given a constant rate of rotation the mercury will naturally assume a parabola more reflective than conventional mirrors.
By introducing sound waves to the liquid mirror it should be possible to induce standing wave nodes which create circular troughs radiating outwards from the centre.
These troughs would then cause sunlight to be focused into a series of focal rings above the surface of the pool.
A heliostat would ensure that line-of-sight would not be a factor when lowering a Fresnel lens onto that series of rings letting us collimate the rings into a beam the width of the mirror which could potentially reach temperatures of several thousands of degrees.
The questions then become; how can I get my hands on that much mercury? Crowd source thermometers maybe? and...
Do you think anyone will care if I carve a happy face on the moons surface?
Liquid Mirror
https://en.wikipedi...id-mirror_telescope
Using mercury is quite an old idea. Just noticed: the first to work was in my old home town! [neutrinos_shadow, Dec 12 2021]
Why are snowflakes so symmetrical and hexagonal?
https://www.youtube...watch?v=ao2Jfm35XeE
Sortof relavant, I promise. [RayfordSteele, Dec 13 2021]
[link]
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So, I can sign you up to send me the first crowd sourced mercury thermometer then? |
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Okay. One down. Only thirty billion more to go. |
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Using spinning mercury as a mirror is a Thing (linky), so that
part at least will definitely work. Adding the standing waves
sounds interesting, but I'm not sure you can get them the right
shape (sine waves are close to parabolic at the bends, but
obviously not in the "straight" bits between peak & trough). |
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A few technical difficulties like gravity and such, but this is
interesting enough to be bunworthy. |
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I was wondering the other night after watching a thing on
snowflake formation whether you could create better mirror
surfaces by depositing some sort of molecular structure that
by the electrochemistry of its surface like an ice crystal would
form a smoother surface than what could be achieved by
polishing. |
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If you're going to dream... |
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I like the novelty of the standing wave approach. It'd be
worth a thought experiment as to how well the focus would be
in outer space. |
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It would not be optimal for focusing the maximum amount of light for this application, but a morphing/focusing mirror bears experimentation for sure. |
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Can I sign you up for the second mercury thermometer shipment then? |
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p.s. it was your anno on my lightbender posting that made this pop into my head.
Thought you should know. |
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That was my first new brain-fart in almost two years. |
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Seriously. Thank you. I was wondering if it would come back again... it's been a while. |
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What matters is that they care. |
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//mirror bears//
I suspect this idea would work better with sun bears. Maybe a
couple of mirror bears. |
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Don't feed the bears. This doesn't bear saying. |
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On a side note; the folks that punched the passes through our Canadian mountains used to let their children dip their arms in jars of honey and let the bears lick it from their fingers, that's how friendly bears are...
...and where our bear problems stem from.
The pictures of this have since been removed from the internet, but the fact remains. |
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...we weren't really talking about bears were we?
<heavy sigh> |
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Further aside, it was said that one might overcome a fear of
bears by throwing a bear a steak and a bag of donuts. |
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Then, watch the bear snub that steak and gobble down the
bag of donuts. When you realize you taste like a steak the
bear will seem more harmless. |
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Forgive me, but is the purpose to create a multi-focal mirror,
so your sunlight is concentrated into rings, or is this supposed
to be the collimation after the concentration mirror. |
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Because the former can be done with a standard mirror, and
the latter defeats the purpose of a maximally focused initial
mirror. |
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(Also, only if you keep a bag of donuts with you at all times). |
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//Forgive me, but is the purpose to create a multi-focal mirror, so your sunlight is concentrated into rings, or is this supposed to be the collimation after the concentration mirror.// |
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Nothing to forgive, I mean both of those things.
Focusing light into concentric rings so that it can be collimated at intensities which would normally vaporize even a diamond lens.
I know the same first effect can be achieved with standard reflective surfaces, it's just that playing with cymatics and morphing surfaces in my head is fun for me so this popped out. |
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Two guys out hiking see a bear in the distance and it charges them.
One guy starts changing his hiking boots for running shoes.
His buddy says; "What are you doing? Your not going to outrun the bear!"
The first guy finishes lacing up and says; |
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"I just gotta outrun you..." |
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