Given that the oreos could be effectively sized and attached to the capsule covering the appropriate surface area how many oreos would be required to withstand atmospheric re-entry as an ablation shield for an Orion capsule sized space craft?
Given that the oreos could be effectively sized and attached to the capsule covering the appropriate surface area how many oreos would be required to withstand atmospheric re-entry as an ablation shield for an Orion capsule sized space craft?
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no math here, but i feel like there is an insurmountable difference between getting blasted with a torch, and blasted with winds so strong they reach hotter than the temperature of the torch. not sure an oreo can withstand that at all
So you’re saying there’s a chance!
My kid used this logic when I said NO
😂 ty for this
Ablation shield is going to be destroyed and only has to survive longer than the reentry period. In theory a thick enough stack of oreos could outlast the erosion from the winds. It would probably need to be a few feet thick though.
The person who produced the video needs to test oreos with a sand blaster to see how long it takes to ablate them from the friction of sand blasting.
Better go with double stuff
Found the scientist
Unless the filling stuf melts and allows the entire wafer to blow away since it's no longer attached to the cookie. I’d think more layers of the thinnest Oreos would be more effective.
Yeah but then the science wouldn't taste as good
I got into science for mouth pippetting and identifying reagents by scent… but then OSHA had to go and ruin everything for me!
Slaps chocolate hull
“She ain’t going anywhere.”
Mega stuff.
Don't think normal ablative shields can withstand a sandblaster.
On reentry the capsule goes faster than the speed of sound. The air cannot move away fast enough. This creates enormous pressure and heat. Sure, some friction aswell. But I'm pretty sure an ablative shield primarily need to ablate, and he able to withstand high pressure with crumbling while in combination of some friction.
For example, cork can be used as a heat shield, but would not survive a sandblaster.
If reentry was mainly friction pretty much nothing could withstand reentry.
Upvote for the cork fun fact. I'm very sad no one else wrote about that.
Well would it be preferable from a deterioration standpoint to be stacks of oreos or, say, one giant oreo made of standard oreo material?
I'd imagine any gap between the Oreos is a potential failure point where hot gas can slip between. Circles don't fit together neatly, the best you could do with normal Oreos would probably be many layers in a hexagonal grid pattern, each one shifted so the centers of the Oreos behind them are blocking the gap between the Oreos in front of them.
One big Oreo could mostly ignore that.
Either that or make hexagonal oreos. Nabisco would probably go for that for the really large order, and the positive PR.
That and, of course, hexagons are the bestagons.
Okay, now i want hexagonal oreos.
I need to know the answer to this.
I feel like the much bigger issue is delamination, the cookies are designed to shear apart after all
Well there's also a difference between a material which doesn't erode or catch on fire, and one which is good at insulation. We want the space capsule skin to be blazing hot on one side and cool on the other. We don't have those properties for Oreos but there's a reason that space agencies use metal and ceramic tile instead of a cookie or breadlike material
But as the mass increases, more kinetic energy needs to be lost, which would required even more shielding/harder areobraking.
Assuming the vessel reach safe parachute opening speed at the same altitude
What if you put the Oreo layer inside some other layer that can withstand the winds erosion?
I feel like the wind catching their edges would be the real issue here. But if we posit custom-made giant square Oreos I think this issue can be overcome.
To be all technical and stuff, heat shields ablate due to compressive heating from the bow shock of the thin air in front of the heat shield. They are sort of evaporating off, but at a much higher temp than that torch can produce. It isn't friction that causes them to ablate since the atmosphere is too thin to really produce much friction at 60 to 80km up.
The surface of the AVCOAT heat shield on Orion is designed to reach 4000f (2200c) without burning thru. Admittedly it could have done a better job of it on its last flight.
The Chinese were once trialing wood as a heat shield. I'm not sure how that worked out for them, but basically wood would boil off its volatiles fairly quickly and then turn into a carbon foam which generally works well as heat shield material.
Step one- build a combination sandblaster + blowtorch.
Can you combine a sandblaster with a torch....though maybe we shouldnt consider that incase of the Mad Max-esque wars of 2030
Well not a oreo ... more like 100,000 oreos maybe?
1 billion oreos just to be safe
Double stuf obv
We all know half of those are going into the engineers’ mouths.
And I say that with zero judgement.
something something mach 5
Ok so like more than one then.
Right so how many would it take?
I think that exact reason is why they didn't use oreos in the first place.
You just have to remove one of the cookies, lick it and stick it.
Just add msg 🤣
Real ones often use cork. It's not supposed to withstand reentry. It's supposed to be consumed during reentry.
Well, if we had a Jupiter-sized oreo, surely that will make it past earth’s atmosphere.
So we talking like a whole pack of double stuffed stacked per square inch or..
Sooo instead of 1 Oreo, we use 2 mind blow
Not with this attitude
That's no argument against it, just an argument for more number magic!
[deleted]
Some of his mannerisms were matching Gary Oldman in “Leon” vibes
Just need to have a gigantic glass of milk descending along side Orion.
My understanding is plasma is created from friction amongst air molecules (a very small, thin layer above the surface of the object, and the body of air outside). I thought that on re-entry, the object does not experience direct friction, but instead is affected by the heat of the plasma created from air friction.
But have we considered if they have been dipped in milk. Maybe the moisture provides even more heat protection…Checkmate atheists?
If you baked the Oreo around the space craft , you might be the creamy center.
Use better glue then
Only one way to find out!
Is it really just windspeed that causes the heat? So if they controlled the decent at a slower speed there would be no need for heat shields?
Not with that attitude it cant!
So like a whole pack?
It’s never just an Oreo. It’s the whole family sized bag or none at all
They did not do the math
Well not with THAT attitude!
You are wrong. On the very center of the nose cone there is no shear velocity. So wind is irrelevant for an Oreo near the center of the reentry vehicle. There will be some pressure, sure. But most solids are ok under a few atmospheres of pressure. The thermal properties are the main thing, and this test checks that reasonably!
Average temp of a non-specialized, handheld blowtorch - 2400° F -- Average temp on re-entry - up to 5400° F, so yeah - not a real fair comparison, but Oreo sure impresses!
China used a 6" thick piece of wood. Wood burns at a lower temperature than 2400f.
Compressed wood is actually surprising fire resistant.
Source: a random show on nat geo I watch a few months ago about a skyscraper they just built somewhere that has no steel beams. Only wood beams.
Also chemically treated wood can be very fire resistant. It wasn't nile red, but it was the youtuber who covered the 1930's chemistry book and he did the stuff it talked about and one of them was to make a "lab desk" and the chemical treatment made it both significantly flame and acid/base resistant. Doing compressed wood and treating it combined would add quite a lot to the overall resistance and make it much more viable at least from a thermal standpoint.
That's my man StyroPyro. Never forget that name.
Styropyro, a man with so much testosterone that it's literally a medical issue
The purpose of ablative coating is to burn away not to withstand the heat.
What if they were double stuff?
Bro that's only double the temp. I can do math. Just put two layers of oreos!
Maybe that's where double stuff comes from...
Just make the oreo thicker, duh
So 2 oreos?
For a proper test of this, don’t use an oreo fresh out the pack. Use one that has been left to sit in a vacuum chamber for a while, that will remove any trace of moisture within it. I highly suspect it will not perform anywhere as impressive
This was my first thought. There best ablative material is water
Obviously you'd dunk them in milk before re-entry. Clearly you don't work for NASA.
it might still do pretty well. i saw a video a while back testing the fire resistance of carbon foams made of white bread, and it was pretty impressive. oreos should be pretty close chemically, and kind of similar structurally
From an internet search, Orion's heat shield surface area is ~20 m2 (~222 ft2 ).
An Oreo has a diameter of 4.45 cm (1.75 inches).
Area of the Oreo is pi*diameter2 / 4 = 15.56 cm2.
If you cut up the Oreos to completely cover the surface area with no gaps, it would take 20m2 / 15.56 cm2 = ~12,850 Oreo's.
If you left the Oreos as circles:
We'll assume the 20 m2 is a flat surface for simplicity which will provide a rough estimate.
If we pack them in a hexagonal lattice, the packing density is ~0.9069. So 12850 * 0.9069 = 11660 Oreos.
But... this will leave ~9.3% of the surface unprotected. To fill that gap, we could add a second layer of Oreos packed in a hexagonal lattice, which would result in a total of 11660 * 2 = 23,320 Oreo's.
How much would that cost?
A Costco pack of Oreos contains 156 cookies and the cost is $13.49 before tax. It would take 23320 / 156 = 149.49 Costco packs which we'll round up to 150 because you can't buy a half a pack.
So 150 * $13.49 = $2023.5 + tax.
I mean, you have to imagine that the order would be about double that to account for breakage and snacking during assembly.
NASA would likely just go directly to Nabisco and buy bulk without the resale markup.
Does anyone know the margin Costco makes on Oreos?
Love it XD
When food mysteriously disappears from a grocery store like this, they call it "shrink" in industry lingo.
12%! So honestly maybe not that much in savings
Don't show our for profit space program this.
The real cost is labor. Gotta get a guy to twist em all and lick the icing out of the middle.
That’s incredible how durable they are to a torch but if I leave it one second too long in my glass of milk it dissolves and my day is ruined
That's why an Oreo based ablative shield will never work in the Milky Way...
They also have a tendency to dissappear from my cupboards.
I'd love to understand why this happens. I have a friend that swears this is a good test showing that oreos are unhealthy.
That's because the video is fake and the oreos in it are made of metal. Seriously, one is glowing red at the end.
You know things other than metal can glow red when hot enough right
What we are seeing done with oreos we can also achieve with a paper cup filled with water.
Anyway: A space capsule is going to be subject to quite normal temperature air, it's the friction with the air that superheats the hull. That friction comes from the capsule's direct interaction with the physical force of wind resistance, and I don't think the cookies will survive at speeds up to Mach 25.
The problem with Oreos is that while they can stand the heat, they probably wouldn't be able to hold together from the forces of space travel.
What I hear you saying is we need to use Hydrox cookies then
Basically yeah. Only the real deal has a chance.
It's the same as that viral "fire proof" pineapple skin. They're not particularly fire proof, it's just the water contents. So it's just some mass with quite high water content.
A few thousand Oreos should do it, because that will attract plenty of gullible fools to tag along. We can then use their bodies as the heat shield.
So this problem then simplifies down to…
According to this: https://www.nasa.gov/missions/meet-nasas-orion-spacecraft/#:~:text=The%20bottom%20of%20the%20capsule,Forward%20Bay%20Cover the heat shield is approximately 16.5 ft in diameter or 5.02 meters in better units. Using pi*r2 as an approximation (since the shield is not quite flat) you get an area of 19.79 m2.
According to this: https://qa.inkedibles.com/5467950/What-size-is-an-Oreo-cookie (though they tend to vary) Oreos are approximately 4.45 cm in diameter or 0.0435 m, and since they are flat, and mostly circular, their area is 1.49×10-3 m2.
If we divide the first by the second, you get 13281.8 cookies needed to cover the area, or 13282 if you only have whole cookies. We can technically divide this number in half since each Oreo has two cookie bits coming out to a final 6641 Oreo cookies needed. This doesn’t take into account that circles cant properly tessellated to fill a space so there would be gaps, but it’s a decent enough ball park. You can always crush some extra and fill the gaps on your reentry vehicle.
So.. nobody seems to have done the math on this yet.. here it goes:
Is it possible? Well technically no heat shielding is required for launch or in space, it’s needed for re-entry where speeds exceed 28.000 km/h and temperature exceeds up to 3000 degrees Celsius.
Let’s ignore re-entry as Oreo’s would not suffice to shield for re-entry. For launch temperatures only go up to 200 degrees Celsius, which Oreo’s could unironically shield against, easily.
The surface area of an Orion space capsule is 90m2. The surface area of an oreo cookie is about 0.005m2 (50 cm2). We’d have some gaps to fill if not using neatly matching cookies, but let’s melt some of them down to fill the spaces in between with “oreo paste”.
To cover 90m2 with the surface area of oreo cookies we would require 18.000 oreo cookies. A single oreo cookie thickness would be able to shield the maximum few hundred degrees Celsius experienced when launching a space ship. Not that we would really need the shielding, it would just be an inefficient but hilarious space craft decoration.
This is only covering the Orion space capsule, not the booster system needed to escape orbit. But that would get so hot at launch the oreo’s would be wasted.
With the current setup, astronauts could exit the capsule and re-claim the oreo’s for consumption (if safe in terms of radioactivity, not sure on that part).
Tldr; 18.000 oreo’s.
Re-entry survival was the entire point of the thread though! Surely we can look at survivability of an Oreo to the flame above and extrapolate at least POTENTIAL survivability of a given layer of oreos (obviously we'd need to make some allowances for adherence) and then use that to get to a better number to survive re-entry.
Wow i must say.. You will need to show this to Trump and Elon - this new discovery will most likely be good to investigate for SpaceX intended use in🚀 And Oreo's stock will skyrocket as a side bonus👏
Oreos would make a terrible ablative heatshield, even at lower temperatures. The structure is all wrong. The cookie part is too brittle, it wouldnt ablate evenly so much as it would crumble, and it's held on in the wrong direction which would make it too easy to lose the entire top half.
Unfortunately I don't consider this a comparable test since re-entry heat is mainly caused by compression with some friction. The oreo's ability to withstand high temperature is surprising but can it withstand high pressures? we need more data.
ablation shielding do more than heat protection. It's also responsible for preventing strong wind from, yk, breaking the whole space capsule
The answer is probably several meters thick and a bad idea for many many reasons. Part of the design of an ablative shield is being smooth so the capsule doesn't roll or tumble during entry because of friction torques. The materials oreos are made of obscure charring, making it "look" like the oreo is unaffected even though it is quite burn't; but they would still pit and crumble like the dickens during reentry because its like being blown apart by sun temperature sandpaper. Yes; an oreo of a certain size would wear away slowly enough to work in the role; but you probably would have been better off using plywood, pumice, astronauts or even frozen feces mixed with superglue as an ablative material. All would be far less crumbly and come apart in smaller chunks than an apartment block sized oreo.
I dream of a day when the module can return to splash down in a massive milk reservoir and be harvested for slightly toasted Oreo delights.
Honestly, you can make carbon foam out of bread, so if you did the same with a giant oreo cookie, and made it thick enough, you might be able to survive reentry on it
Now this is a person with a plan!
I don't know the math, but I do know aviation.
The simple answer is, you can't. An ablation shield MUST be one contiguous surface, and as smooth as possible. There's no way in which you could organize the oreos that the gaps between them wouldn't cause them to sheer off from the immense forces being applied to them.
How about grinding them up to make an Oreo ceramic?
They use tiles, not a contiguous surface. So the tiles break away when the ablation material is consumed.