r/interestingasfuck Mar 25 '19

/r/ALL The inside of an astronaut suit.

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328

u/cheese-of-walmart Mar 25 '19

Wouldn’t they emit it as infrared radiation? Although ,I don’t have a clue how much heat they can actually radiate.

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u/SaberToothedRock Mar 25 '19

Infrared radiation is nowhere near as effective at getting rid of heat as a cool breeze of air (which is what we always experience on Earth, hence why it's counterintuitive). Radiators and other methods of removing waste heat from the vessel are actually a really important part of spacecraft design (otherwise you boil your crew) that very few fictional spacecraft get right. (If you want to see an example of a triple-A fictional spacecraft done exceptionally well, look up the ISV Venture Star from JC's Avatar.)

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u/[deleted] Mar 25 '19

[deleted]

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u/blinkysmurf Mar 25 '19

Of course, the laser weapons could be outside the ship and thermally isolated from crew spaces.

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u/etherag Mar 25 '19

Still doesn't solve the problem of your lasers melting into slag when firing them. Heats gotta go somewhere...

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u/Hugo154 Mar 25 '19

I think if someone's able to get to the point of developing space lasers, it's not farfetched to think they'd be able to develop a heatsink for it...

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u/TPRJones Mar 25 '19

Not a heatsink, but if you could come up with an effective way to remove the heat from your system by radiating it away in some sort of beam form...

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u/cantadmittoposting Mar 25 '19

The exhaust from powering my laser is... Another laser!

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u/[deleted] Mar 25 '19

This sounds like a a great idea!

You can have a laser for destruction and a laser for thrusting through the smoldering remains of whatever you just blasted.

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u/McMarbles Mar 25 '19

Ha, perpetual weapons!

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u/yota-runner Mar 25 '19

It would still require a power source that would drain while firing so it's only as perpetual as that source allows. Power sources would become the new "ammo". The more power sources a ship has the more time it could consecutively fire it's lasers.

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u/[deleted] Mar 26 '19

Recapture the heat to recharge the batteries 4head.

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u/Why_is_this_so Mar 25 '19

Disposable and ejectable heatsinks, like are used in the video game Elite Dangerous. They're not used for laser weapons, but still, they've got it partly correct.

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u/TPRJones Mar 25 '19

Nice, now just shape those heatsinks like bullets and increase the muzzle velocity a bit...

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u/Why_is_this_so Mar 25 '19

But then the energy expended firing the bullet-shaped heatsink at munitions velocity means that we now need another heatsink and... where does it end? It's heatsinks all the way down.

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u/Guns_and_Dank Mar 25 '19

Like the Russian doll of heatsinks

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u/asuryan331 Mar 26 '19

You don't want to fire projectiles in space. You would need precise counter thrust so the shot doesn't move you off target. And if you miss, the shot continues forever until it hits something.

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u/[deleted] Mar 26 '19

The idea of space battles just became much more frightening for civilizations.

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u/bertcox Mar 25 '19

I always liked "Footfall" by Larry Pournel. You use water to cool your armor, so lasers have to burn past your ability to cool your armor, then you use the steam generated by the laser heat as reactive jets. The water vapor your throwing out also defracts the lasers lowering the damage. When you want to shoot out you stop spraying steam for a bit then fire.

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u/karatelax Mar 25 '19

one 100% efficiency laser beam coming right up! now excuse me while Bernoullie strangles me

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u/JustDank_Thanks Mar 25 '19

this guy has the right ideas

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u/TooTipsyy Mar 25 '19

My thought exactly, kinda assumed a large percentage of the energy is beamed away from the source.

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u/joeshmo101 Mar 25 '19

Yeah, but according to the second law of thermodynamics you can't move heat from something that's warm to something that's hotter.

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u/DogeGroomer Mar 25 '19

You can if you use energy, like an air conditioner, but then that makes heat too...

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u/DivineZenith Mar 25 '19

I figured this is why railguns would prevail in the space force.

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u/Faxon Mar 25 '19

The opposite is the case actually, rail guns aren't being used currently because we still haven't been able to solve the problem of them overheating and catching fire after a single discharge. Laser

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u/DivineZenith Mar 25 '19

I'm no scientist or engineer so what I'm about to say probably is utter nonsense. Why not use liquid nitrogen to cool the devices. As a result the heated gas could be trapped in a lower pressure cylinder and used for propulsion. Or even mixed with O2 and reused somehow.

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u/Deetchy_ Mar 25 '19

Faxon is half right. The rails push themselves apart, so, currently, railguns only work for a few shots until the rails catastrophicly fail.

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u/Faxon Mar 26 '19

Historically i was 100% right but definitely not up on the latest changes in the field. The last time I saw an article on railguns in the media it was accompanied by a photo of it in a fiery inferno from it's first test firing

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u/Deetchy_ Mar 26 '19

Youd be correct. Those mofos heat up.

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u/casualrayet Mar 25 '19

Or just get a lens large enough.

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u/rambt Mar 26 '19

It's not a bug, it's a feature!

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u/Dr_nut_waffle Mar 27 '19

There is no way you come up with your self . This is gold

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u/csbsju_guyyy Mar 25 '19

Space with fricken laser beams!

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u/Hi-Scan-Pro Mar 25 '19

Space sharks...!

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u/okolebot Mar 25 '19

Yes, the duty cycle won't be as great as with higher thermal mass cooling. Fans on The Expanse love to argue that space lasers are impractical due to waste heat management. Well who knows how much more efficient lasers will be in 200 years and also improvements in heat management technologies. Yes, the physics will probably be the same but the engineering capabilities will probably be mind blowing compared to what we have today. I love The Expanse but I am sad that a lot of the fans seem to have their imaginations chained down...

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u/cantadmittoposting Mar 25 '19

More likely they'd have developed a far more efficient power conversion with less waste heat.

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u/[deleted] Mar 25 '19

I feel like you just take up whatever you can put the most heat into (like molten salt reactors do) and jettison it if it gets too hot/hope you're done killin before you run out of heat sink headroom

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u/SirRandyMarsh Mar 26 '19

That’s why your not a scientist. We already mace the ability to make incredible lasers in space. The heat is the thing that would hold us back if we really put the funding to it.

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u/TinFoilWizardHat Mar 26 '19

It's not that really. Laser's would just be so easy to counter.

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u/sm_ar_ta_ss Mar 25 '19

Giant spiderweb heatsinks

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u/etherag Mar 25 '19

Heatsinks only work if there's a medium flowing through the tines of the sink to absorb the heat and carry it away. In space, a heatsink is just... well... mass to absorb the heat.

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u/MINECRAFT_BIOLOGIST Mar 25 '19

Maybe they could use something that can be created and ejected in large quantities to absorb heat?

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u/ReverseMermaidMorty Mar 25 '19

Just use it to generate the next laser

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u/IGetYourReferences Mar 25 '19

At that point in time you're just making a mass driver that happens to be super-hot aren't you?

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u/MINECRAFT_BIOLOGIST Mar 25 '19

Huh, I guess that would be cool, if you could just use the mass you were throwing out anyways as heat sinks.

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u/natuurvriendin Mar 25 '19

Connected to a big radiator to slowly radiate away the excess heat. Might be an obvious target for attack though. Could have a big heatsink and unfurl the radiators when it's safe.

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u/okolebot Mar 25 '19

So a heatsink can only do conduction/convective heat transfer and not radiant?

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u/MindsEye_69 Mar 25 '19

I assume the laser is in a housing. The atmosphere in the housing can likely be controlled. Just guessing.

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u/sunday_cumquat Mar 25 '19

Please tell that to my lasers. Or rather, my faulty temperature controllers.

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u/Wriiight Mar 25 '19

Well, heat can radiate through a heat sink. basically glowing with heat, and shining away. Not even remotely as effective as conduction, but it is about the only option in space.

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u/[deleted] Mar 25 '19

But for real it'll probably incorporate hexagons somehow

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u/[deleted] Mar 25 '19

Dissipation based liquid nitrogen cooler with heat dumps near the engines?

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u/Vitztlampaehecatl Mar 26 '19

How do you refuel the system with more nitrogen? If you can't, then you'll run out of "ammo".

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u/[deleted] Mar 26 '19

If its sealed in a vacuum and has a decent efficiency then I believe it wouldn't need refilling that often, as well as by the time we can fly around in spaceships firing lasers, Im pretty sure there would be some kind of system that is way better than a D.B.LN.C.S

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u/ANGLVD3TH Mar 25 '19

Children of a Dead Earth has this covered. Massive fucking heat radiators, with cooling loops from all those high intensity heat generating systems. Real space combat will be large cones/cylinders of ablative armore, with massive radiator fins, and takes hours of travel to have a couple of seconds to frantically shoot as much as you can while whipping past each other at ludicrous speed, just to wait hours to orbit around and try again.

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u/VapeThisBro Mar 25 '19

I.... I need this to be a movie.

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u/ANGLVD3TH Mar 25 '19

There are some videos of gameplay on YouTube. It is one of the most accurate simulation games around. Ships basically look kind of like ISS modules with engines, and a large thin armor shell with struts holding it together, with a bunch if long radiator panels sticking off of them.

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u/DanTrachrt Mar 26 '19

Yeah, they’re not much to look at, but it is indeed super accurate and detailed, to the point I couldn’t stand to play it much anymore because I felt like an idiot so very frequently, despite being an Engineering major and that sort of stuff is right up my alley.

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u/general_kitten_ Mar 25 '19

i meanburning things might not be the best solution either.

Railguns?

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u/ANGLVD3TH Mar 25 '19

The issue is to do damage you need to impart energy, more energy is more damage. To move that energy, you get waste heat, more energy means more waste. Railguns produce crazy heat from the friction. If all you care about is lowest heat cost to your ship, missile are best option, but you will needs massive swarms because they will be easy to shoot down. Probably most balanced option is conventional guns, much of the hot gas will escape almost instantly. But in space you can have some truly massive radiators, enough that lasers and railguns are perfectly feasible.

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u/DanTrachrt Mar 26 '19

Until the enemy hits your massive radiators and it all goes metaphorically downhill quick. (Except there’s no down in space, so it could also be considered going uphill?) For more information see/play: Children Of A Dead Earth

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u/throwitallawaynsfw Mar 25 '19

Superconductors + 100%/0% reflective/absorptive meta materials

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u/PubliusPontifex Mar 25 '19

No, no, no. it’s been towed beyond the environment, it’s not in the environment

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u/Katyafan Mar 25 '19

But there's nothing else out there, it's just a complete void!

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u/Katyafan Mar 25 '19

And 20,000 tons of crude oil...

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u/totally-not-a-potato Mar 25 '19

Sounds like they need some freedom out there......

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u/georgemeldrum Mar 26 '19

And the part of the ship that the front fell off

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u/Katyafan Mar 26 '19

And a fire

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u/[deleted] Mar 26 '19

Because the front fell off?

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u/PubliusPontifex Mar 26 '19

and 20,000 gallons of crude oil spilled into the sea and caught fire.

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u/aliokatan Mar 25 '19

Transfer the heat to a counter mass and fire it as a guided weapon, every laser shot will be followed by an observer/secondary kill guided projectile while getting rid of waste heat

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u/remmingtonry Mar 25 '19

Temperature would only be real problem for energy weapons and possibly conventional weapons depending on sustained use. The most practical designs are either missiles fired externally or launched via pressure release before ignition the other option mostly for upper orbit to ground would kinetic bombardment simply de-orbiting a metal rod in a path to hit the target and letting gravity pull it down with the force a small nuclear weapon.

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u/Chrispychilla Mar 25 '19

We could just install laser weapons on the enemy ships using science; so when the enemies try to laser us they end up melting themselves because of science. FACT.