Astronauts attached hundreds of material samples to the outside of the International Space Station and left them exposed to space for years

[u/Mike_ZzZzZ]

[u/Mike_ZzZzZ]

This image is from Materials International Space Station Experiment (MISSE) 2, part of STS-105 mission in 2001. Full report is at https://ntrs.nasa.gov/api/citations/20070002707/downloads/20070002707.pdf

[u/Best_Poetry_5722 → u/Mike_ZzZzZ]

Just to peak pique curiosity:

"Forty-one different polymer samples, collectively called the Polymer Erosion and Contamination Experiment (PEACE) Polymers, have been exposed to the low Earth orbit (LEO) environment on the exterior of the International Space Station (ISS) for nearly four years as part of Materials International Space Station Experiment 2 (MISSE 2). The objective of the PEACE Polymers experiment was to determine the atomic oxygen erosion yield of a wide variety of polymeric materials after long term exposure to the space environment. The polymers range from those commonly used for spacecraft applications, such as Teflon (DuPont) FEP, to more recently developed polymers, such as high temperature polyimide PMR (polymerization of monomer reactants). Additional polymers were included to explore erosion yield dependence upon chemical composition."

[u/LadyKataka → u/Best_Poetry_5722]

"to determine the atomic oxygen erosion yield" means to determine how much they deteriorate due to losing oxygen?

[u/Mazon_Del → u/LadyKataka]

At the altitude of the ISS, they aren't in "true" vacuum, in the sense that it's not 100% void. They are still in a VERY thin atmosphere. When the ISS was first put up, they thought that 'drag' would be negligible depending on the frontage of the station, but with some experimenting they realized that by having the solar panels rotate 'edge-on' for flight when the station went into the Earth's shadow, they actually saved a fairly significant amount of velocity over time. Meaning, they didn't have to spend as much fuel to maintain orbit as they used to.

Now, this atmosphere is mostly, but not exclusively, oxygen. You might be familiar with "O2", because Oxygen likes to have a buddy, and in the absence of anyone else it'll buddy up with another Oxygen atom and be stable enough. O2 is the form of oxygen we breathe. The trick is that up there, UV light straight from the sun smacks right into these pairs and splits them up. Normally in a much denser part of the atmosphere lower down, they'd immediately bump into another atom to bond again and nobody's the wiser. But up there, they just don't HAVE anyone else to bump into, so they stay as just a free floating Oxygen atom. So, now not only do you have a 17,500 mph wind (albeit a VERY thin wind...) but it is made out of a substance that REALLY likes to rip atoms out of other molecules.

So you have mechanical erosion (the impact of the atom) and chemical erosion (the atom stealing part of whatever it hit).

So the "atomic oxygen erosion yield" would be a measure of how much material was lost comparatively. I'm sure they have plenty of sensor data to tell them a good idea about how much rarified Oxygen overall was run into, but by having all these samples exposed at the same time, you don't even really need that data to do a comparative analysis. That one fourth from the right on the top that looks like fabric? Clearly withstood that time far better than either of its horizontal neighbors.

[u/CHIGATRON → u/Mazon_Del]

This is a great, well written and easy to understand explanation. Thank you for the info!

[u/Mazon_Del → u/CHIGATRON]

Glad you liked it!

[u/MaritMonkey → u/Mazon_Del]

That one fourth from the right on the top that looks like fabric?

If it's anything like the nylon straps we find on warehoused gear, it looks fine but actually has the structural integrity of cigarette ash. :D

(Seriously though thank you for that amazing write up)

[u/Darlantin → u/MaritMonkey]

Apparently it is ppd-t, commercially known as Kevlar.

[u/MaritMonkey → u/Darlantin]

Thank you, I got distracted and totally forgot to look that up!

[u/Mazon_Del → u/MaritMonkey]

True! Appearances can be deceiving, and I wonder how many of these fell apart on the way back home.

[u/TheStorytellerTX → u/MaritMonkey]

Your comment reminds me of the old lawn chairs with the plastic straps you could replace. The ones that just sat out in the Texas Heat for years would be fine until you actually touched them, then the straps would fall apart as if Thanos had snapped his fingers and targeted furniture.

[u/MaritMonkey → u/TheStorytellerTX]

Lol my mental image was of those (no spoilers) folks from Interview with the Vampire but Thanos is probably a lot more relatable. :D

Also somehow thinking of those lawn chairs (in FL not TX but still) brought a whole wave of nostalgic context along for the ride.

[u/elocmj → u/Mazon_Del]

You must be a teacher the way you explained so well something so complex to such simple-minded folks as redditors. Nicely done

[u/Mazon_Del → u/elocmj]

Daw, thanks! Nah, I'm just a nerd that programs videogames.

[u/nochinzilch → u/Mazon_Del]

Wait, so the atmosphere has more oxygen and less nitrogen up there?

[u/sgtbackpain03 → u/nochinzilch]

Yes, in terms of percentage. It's like 80% atomic oxygen (O), and 15% molecular nitrogen (N2) (though the exact makeup is highly variable, from my understanding).

A single atom of Nitrogen is less dense than a single atom of Oxygen, but when the Nitrogen is bound to another Nitrogen, it's more dense than just a single Oxygen.

[u/cat-n-jazz → u/sgtbackpain03]

And if anyone is wondering "why doesn't the UV light split up the N2 like it does the O2?" (i.e., why are we comparing N2 with O rather than N with O or N2 with O2)?

The answer is that the N2 bond is significantly stronger than the O2 bond because nitrogen uses a triple bond rather than oxygen's double bond. So, UV light of a certain energy can split the O=O, but not the NΞN.

Why does nitrogen triple bond with itself when oxygen only double bonds? That's a whole lecture of valence electrons and covalent bonding, but the short version is that nitrogen atoms, with 5 valence electrons each, can "share" three electrons each to get to the 8 that they want for maximum stability. On the other hand, oxygen with 6 VEs can only "share" two electrons each to get to that stable octet.

^{bonus: if you've followed the pattern here and asked "but then why doesn't carbon quadruple bond with itself?", imagine you and another person are double high-fiving while also touching genitals, three bonds, good luck also getting your spines to touch -- the fourth pair of electrons that could be shared are exactly opposite one another and there's no way to orient the atoms so they can also be shared without breaking one of the first three bonds. You can get quadruple bonds in transition metals when the d-orbitals become available, but then we're really into the weeds here and that's college-level chemistry}

[u/Obsidiated → u/cat-n-jazz]

If chemistry had genital binding i might have paid more attention to physics boring cousin.

[u/elictronic → u/sgtbackpain03]

Photodissociation occurs much more frequently with O2 vs. N2 at a rate a few orders of magnitude more frequent causing even more of this trend.

[u/SwordsAndWords → u/Mazon_Del]

It looks like the dark blue one two up and two right from the bottom left corner suffered the least degredation, but maybe it only retained its dark color so it's hard to see what happened. Any idea what that material is?

[u/r_xy → u/SwordsAndWords]

found this paper on the mission and i think its the pyrolytic Graphite described in §5.4. It makes sense for this sample to stay dark as unlike the other samples, it is not a polymer. However, the comparison image in the paper shows that it does actually look quite different and it did show significant material loss.

[u/Festivefire → u/Mazon_Del]

I've always found it odd that this process is called oxidization even when it's being done by molecules other than oxygen.

Like Fluorine, is also extremely hungry for electrons that other atoms currently are holding, and will rip atoms out of formation to steal them to satisfy its electron balance, and we also call this oxidization, and refer to fluorine as an extreme oxidizer, even when no actual oxygen is involved in the process.

[u/gruffen2 → u/Festivefire]

Oxidation either came first or was more well known at the time. Given your example of “extreme oxidation”, it could also be considered the baseline for the process.

[u/sushirolldeleter → u/Mazon_Del]

Did you stay at a holiday inn express last night or something

[u/PlasticMegazord → u/Mazon_Del]

That was extremely interesting and well written.

[u/AndaleTheGreat → u/Mazon_Del]

I got to agree with everyone else that this is an awesome write-up and definitely needed.

Thanks to you I now also have an incredible curiosity of what it's like to experience incredibly high velocity but very thin airflow.

[u/halcyonforeveragain → u/AndaleTheGreat]

Can I interest you in dust storms on Mars?

[u/KEPD-350 → u/Mazon_Del]

Thanks for the writeup!

[u/tld15 → u/Mazon_Del]

This answer was so compelling and delightful to read. Made my brain happy to not have an AI scare.

[u/ptolani → u/Mazon_Del]

I hadn't really considered how much the solar panels must be rotating all the time anyway as they go around the earth.

I wonder if future space stations (if there are any) will be designed to be slightly more aerodynamic?

[u/DiscoBanane → u/LadyKataka]

No, due to gaining oxygen. They aren't in a vacuum they are in low orbit, there is oxygen from our atmosphere hitting these at 27,600 km/h, and it oxydize them in fact faster because the speed act like heat at an atomic level.

[u/Paulschen → u/LadyKataka]

Maybe due to the oxygen radicals present in LEO?

[u/DoubleBlade759 → u/Best_Poetry_5722]

Sorry, it’s to pique curiosity
Thank you for the quote!

[u/Best_Poetry_5722 → u/DoubleBlade759]

That is one word that isn't often used in my vocabulary library lexicon. It is now!

[u/Isosceles74 → u/Best_Poetry_5722]

I am certainly at peak curiosity right now

[u/Darc_vexiS → u/Isosceles74]

There’s alot of responses to peek at.

[u/__WanderLust_ → u/Darc_vexiS]

Fun grammar fact; alot and a lot are different and the one you want to use for the sentence is "a lot". No judgement, easy mistake.

[u/godisapilot → u/__WanderLust_]

Another fun grammar fact; ‘alot’ is not a word. No judgement, even easier mistake to make.

[u/nonymousbosch → u/godisapilot]

alot

[u/__WanderLust_ → u/godisapilot]

Ope, I spelled allot wrong lol, ironic 🤣

[u/Agreeable-Desk5393 → u/godisapilot]

The little grammar goblin inside me just audibly relaxed

[u/worrymon → u/Darc_vexiS]

I'll look in a second, my peke is barking.

[u/spekt50 → u/Isosceles74]

Im more curious as to how PEEK performed however.

[u/lechiengrand → u/Best_Poetry_5722]

I like the example: "your view of the highest point stirred my curiosity" or "your peek at the peak piqued my interest" - it's helped me remember there's a difference ever since 😄

[u/Unlikely-Answer → u/Best_Poetry_5722]

while your adding words, the word for a personal vocabulary library is lexicon

[u/dark_crystals → u/Unlikely-Answer]

you're* ...sorry

[u/Linkruleshyrule → u/Unlikely-Answer]

If you have trouble spelling, it's a dyslexicon

[u/Wonderful_Night9071 → u/DoubleBlade759]

honestly cannot believe you posted a spelling correction and did not get downvoted into oblivion. what strange alternate internet is this?!

[u/dastree → u/Wonderful_Night9071]

I think it's because they seemed like they were trying to be helpful vs smug about it. At least that was how I read it

[u/LengthinessAlone4743 → u/Best_Poetry_5722]

I’m guessing these are all potential exterior materials for a long range ship or building materials for a moon base?

[u/Brisket-Inferno → u/LengthinessAlone4743]

Yeah I'd like to know before having to search it.

[u/Predawnlemonade → u/Best_Poetry_5722]

You should have done PEEK curiosity.

[u/RedOctobyr → u/Predawnlemonade]

That would have been very good. But very expensive.

[u/Preeng → u/RedOctobyr]

Like $5 per screw.

https://www.mcmaster.com/products/screws/material~plastic-1/material~peek-1/

Compared to like 50 screws per $5 for metal screws of the same size.

[u/RedOctobyr → u/Preeng]

Per Google, PEEK can be ~$50-100 per pound. At the other end of the spectrum, polypropylene (PP) is roughly $0.50 per pound. PEEK is definitely a specialty engineering material, and is very expensive. Very strong, and very high-temperature, but very pricey.

[u/BWWFC → u/Mike_ZzZzZ]

O_o

planning for a 3 year exposure (vs. 1 yr) was found to be crucial to the experiment success.

[u/Dreamshadow1977 → u/Mike_ZzZzZ]

Need to read the full file after work, but I'm curious if these were exposed to sunlight/uv as well and how that was taken into account.

[u/TerraByteTerror]

Cosmic Makeup Palette

[u/Rare_Hydrogen → u/TerraByteTerror]

"It's out of this world!"

[u/BaneRiders → u/Rare_Hydrogen]

ET gonna get new eyeshadow, now that would be pretty interesting.

[u/MichelleT88 → u/BaneRiders]

ET doing mascara “ouch”

[u/Laughing__Man → u/Rare_Hydrogen]

just barely!

[u/mog44net → u/TerraByteTerror]

Maybe it's Moonbaliene

[u/Robo_Patton → u/mog44net]

Maybe she’s airborne with it.

[u/jazzmatazztic → u/TerraByteTerror]

Here's our new inspo: "Mercury in retrograde" color palette

[u/Jedi_Bingo → u/TerraByteTerror]

Somehow still manufactured in a dirty warehouse in china somewhere

[u/happysprinkles → u/TerraByteTerror]

Omg that's adorable

[u/DuskyTrack]

"Damn we forgot to label these things, we need to do it again"

[u/alqotel → u/DuskyTrack]

Nonsense, they just do a lick test before, then lick again afterwards to match

[u/FredericaMerriville → u/alqotel]

Ah, I see the geologists have arrived. 🪨

(Source: I am one)

[u/happyjello → u/DuskyTrack]

“Did you use the radiation hardened labels?”

“… what radiation hardened labels?”

[u/Bossuter → u/DuskyTrack]

They dont label them, they have spreadsheets in triplicate denoting what material was used, how and why it was made and its approximate age down to the second. (Apparently /j is needed here)

[u/--OM3GA-- → u/Bossuter]

Joke really flew into outer space.

[u/CaptainONaps → u/--OM3GA--]

They don't teach sarcasm in math class.

[u/mattfolio → u/CaptainONaps]

I dunno, I've seen some pretty snarky proofs.

[u/Robo_Patton → u/mattfolio]

e^{i\pi}+1=0

LOL Euler always gets me.

[u/DarthGuber → u/mattfolio]

Yes but it's derived naturally

[u/az987654 → u/Bossuter]

so even NASA engineers have files like FINAL_V3_FINAL.xls and FINAL_FINAL_v4.xls and KEEPTHISONE_FINAL_DRAFT_FINAL_v2.xl?

[u/riddlegirl21 → u/az987654]

Yes, and least one of those is a pdf copy that may or may not be burned to a disc for backup and secure data transfer

[u/Robo_Patton → u/az987654]

I feel so seen.

[u/flyingbiscuitworld → u/Bossuter]

Triples makes it safe. Triples is best.

[u/delphinous → u/Bossuter]

right up until Elon decides to delete it for some reason or something similar happens

[u/Bossuter → u/[deleted]]

High school dropout actually, I've just read about how much redundancy NASA tends to do so i thought it'd be funny that even their spreadsheets have redundancy

[u/Super_Range45 → u/Bossuter]

Thank you, Commander Data.

[u/Daevryn → u/Super_Range45]

It's Lieutenant Commander Data.

[u/whitestguyuknow → u/Bossuter]

You know... Sometimes humans make jokes?...

Have you ever experienced that part of humanity or nay?...

[u/userhwon → u/Bossuter]

They should have labeled them. DOGE deleted that cloud drive.

[u/dataflow2 → u/DuskyTrack]

Here you go, from OPs attached PDF: https://ibb.co/8nTQTvzW

[u/LayeredMayoCake → u/dataflow2]

Oh cool, abbreviations…

[u/dataflow2 → u/LayeredMayoCake]

If you need it on golden plate, here: https://ntrs.nasa.gov/api/citations/20070002707/downloads/20070002707.pdf

[u/just_a_silly_goose2 → u/dataflow2]

Thank you!

[u/mrASSMAN]

Damn they all got fucked up but the 2nd to last one seemed to fare the best

Edit: found on the materials key, it was Teflon!

[u/Dizzy_Chemistry_5955 → u/mrASSMAN]

last year these dudes came up with an idea to put Teflon in food cause it goes straight through you

https://www.chemistryworld.com/news/teflon-diet-earns-trio-the-2025-ig-nobel-chemistry-prize/4022182.article

[u/mrASSMAN → u/Dizzy_Chemistry_5955]

I think they intended it as a joke but yeah I wanna see someone test that lol

[u/ReturnOfBane → u/Dizzy_Chemistry_5955]

sounds like something Cave Johnson would do

[u/LuukTheSlayer → u/mrASSMAN]

2nd bottom 2nd left looks the exact same too

[u/TelluricThread0 → u/LuukTheSlayer]

Theres several fluoropolymers in a row. I'd expect them to all be as inert as the Teflon.

[u/babysuporte → u/mrASSMAN]

Good eye mrASSMAN

[u/PcGamerSam → u/mrASSMAN]

The one that lasted the best was the plate holding all the samples in

[u/PerriwinklePortal → u/mrASSMAN]

Almost slipped right by you

[u/Profile_Traditional]

The metal frame seemed to stand up the best.

[u/symphonicrox → u/Profile_Traditional]

but those screws just disappeared!

[u/MashTactics → u/symphonicrox]

Can't have shit in low Earth orbit.

[u/DampSleepyHollow → u/MashTactics]

Wrong neighborhood

[u/PerriwinklePortal → u/symphonicrox]

Along with the hubcaps and catalytic converter, damn aliens

[u/sceadwian → u/Profile_Traditional]

They were plastics

[u/yum_raw_carrots]

"Be white stuff" seems to be a good rule.

[u/Pyrhan → u/yum_raw_carrots]

Atomic oxygen is an extremely potent oxidizer.

Like turbo-bleach on steroids.

There's very little of it at the ISS's altitude, but over years, damage to organic materials does accumulate.

(Ceramics and metals are generally impervious to it, though.)

[u/baumpop → u/Pyrhan]

cant forget tardigrades

[u/Marigold16 → u/baumpop]

No. Tardigrades are not very potent oxidisers.

[u/whitestguyuknow → u/Marigold16]

But... we shouldn't forget them either... 😔

[u/OGLikeablefellow → u/whitestguyuknow]

Never forget

[u/Pyrhan → u/baumpop]

That's kind of a myth, sorta...

Tardigrades do very well in the vacuum of space, but they need to be sheltered. 

They die pretty quickly if they're fully exposed to atomic oxygen and the sun's unfiltered UV. See figure 1, bottom left corner from this article:

https://www.sciencedirect.com/science/article/pii/S0960982208008051?via%3Dihub

The line with the white triangles show the tardigrades exposed to vacuum and unfiltered UV. (And that was for just for 10 days!)

The few that survived didn't stay alive for very long after they were rehydrated...

[u/Emergency_Bench_7515 → u/Pyrhan]

Great, this is how we get Tardigrade Necrons

[u/MalaRed007 → u/baumpop]

Always impressed by how much those little guys can survive

[u/Rocinante88119 → u/baumpop]

Trying to spin up a spore drive?

[u/israelff → u/Rocinante88119]

I see a fellow Trekker in the wild. Nice to meet you.

[u/johnny_effing_utah → u/Pyrhan]

I’d say that over years and at 17,500 mph, damage does accumulate. And one appears to have a mini crater.

[u/Fit-Insect-4089 → u/Pyrhan]

It’s almost like they named the oxidation process after oxygen, crazy…

[u/figmaxwell → u/Pyrhan]

> damage to organic materials does accumulate

I’m an organic material, Greg. Can space degrade me?

[u/growingalittletestie → u/yum_raw_carrots]

White Privilege

[u/iolitm → u/yum_raw_carrots]

They win by default.

[u/blue-coin → u/yum_raw_carrots]

Space is racist

[u/papadaddio69 → u/yum_raw_carrots]

It’s worked for me so far

[u/Maxsmack → u/yum_raw_carrots]

Be the case they were being contained in, that seems to have done the best out of anything

[u/Kramit__The__Frog → u/yum_raw_carrots]

We're all made from a little bit of "white stuff" so that checks out.

[u/Doctor_Anger]

Moral of the story: Be made of the aluminum bracket.

[u/nzclknzspfoeSdf → u/Doctor_Anger]

The "materials" here are all just different types of plastic aside from one which is a synthetic graphite. So the lesson is that plastic sucks and degrades, particularly from UV exposure, which we already know.

[u/sojuz151]

Because there is a lot of hard UV out there, lots of oxygen molecules get broken down into individual atoms. Because density is so low, those atoms can survive a very long time without finding a different molecule to react with. And atomic oxygen, being a rather strong oxidiser, is not very picky about what it reacts with.

[u/Tearaway32 → u/sojuz151]

So what you’re saying is… O is a HO?

[u/Xaxth → u/sojuz151]

I love people like you

[u/erksplat]

Forbidden make up.

[u/yetzt → u/erksplat]

It's not forbidden. There are no laws in space.

[u/SilkieBug]

I see some of the samples decided to just duck right off. 

[u/ScratchLatch]

This would be really interesting if it had labels on the materials like the other image in the article.

[u/nonotthat88 → u/ScratchLatch]

Table 1. MISSE PEACE Polymers List.

MISSE

Serial # Material Abbrev. Trade Names

2-E5-6 Acrylonitrile butadiene styrene ABS Cycolac

2-E5-7 Cellulose acetate CA Clarifoil; Tenite Acetate; Dexel

2-E5-8 Poly-(p-phenylene terephthalamide) PPD-T Kevlar 29 fabric

2-E5-9 Polyethylene PE

2-E5-10 Polyvinyl fluoride PVF Tedlar TTR10SG3

2-E5-11 Crystalline polyvinylfluoride w/white

pigment PVF White Tedlar TW10B53

2 -E5-12 Polyoxymethylene; acetal;

polyformaldehyde POM Delrin (Natural)

2-E5-13 Polyacrylonitrile PAN Barex 210

2-E5-14 Allyl diglycol carbonate ADC CR-39, Homalite H-911

2-E5-15 Polystyrene PS Trycite 1000/Trycite Dew

2-E5-16 Polymethyl methacrylate PMMA Plexiglas; Lucite; Acrylite (Impact Mod.)

2-E5-17 Polyethylene oxide PEO Alkox E-30

2-E5-18 Poly(p-phenylene-2 6-benzobisoxazole) PBO Balanced Biaxially Film

2-E5-19 Epoxide or epoxy EP Hysol EA956

2-E5-20 Polypropylene PP Type C28

2-E5-21 Polybutylene terephthalate PBT GE Valox 357

2-E5-22 Polysulphone PSU Thermolux P1700-NT11; Udel P-1700

2-E5-23 Polyeurethane PU Dureflex PS 8010

2-E5-24 Polyphenylene isophthalate PPPA Nomex Aramid Paper Type 410

2-E5-25 Graphite PG Pyrolytic Graphite

2-E5-26 Polyetherimide PEI Ultem 1000

2-E5-27 Polyamide 6 or nylon 6 PA 6 Akulon K; Ultramid B

2-E5-28 Polyamide 66 or nylon 66 PA 66 Maranyl A; Zytel

2-E5-29 Polyimide PI LaRC CP1 (CP1-300)

2-E5-30 Polyimide (PMDA) PI Kapton H

2-E5-31 Polyimide (PMDA) PI Kapton HN

2-E5-32 Polyimide (BPDA) PI Upilex-S

2-E5-33 Polyimide (PMDA) PI Kapton H

2-E5-34 High temperature polyimide resin PI PMR-15

2-E5-35 Polybenzimidazole PBI Celazole PBI

2-E5-36 Polycarbonate PC PEEREX 61 (P61)

2-E5-37 Polyetheretherkeytone PEEK Victrex PEEK 450

2-E5-38 Polyethylene terephthalate PET Mylar A/200

2-E5-39 Chlorotrifluoroethylene CTFE Neoflon CTFE M-300; Kel-F

2-E5-40 Halar ethylene-chlorotrifluoroethylene ECTFE Halar

2-E5-41 Tetrafluorethylene-ethylene copolymer ETFE Tefzel ZM

2-E5-42 Fluorinated ethylene propylene FEP Teflon FEP (round robin)

2-E5-43 Polytetrafluoroethylene PTFE Chemfilm DF 100

2-E5-44 Perfluoroalkoxy copolymer resin PFA Teflon PFA CLP (200 CLP)

2-E5-45 Amorphous Fluoropolymer AF Teflon AF 1601

2-E5-46 Polyvinylidene fluoride PVDF Kynar 740

[u/cursed_franchise → u/nonotthat88]

I thought I recognized 2-E5-8 Poly-(p-phenylene terephthalamide) PPD-T Kevlar 29 fabric!

[u/Phlegmagician → u/nonotthat88]

Those words are all just made up! By scientists, using precise chemical etymology.

[u/le_sacre → u/Phlegmagician]

Spoiler alert: all words are made up!

[u/Super-Pizza-Dude → u/le_sacre]

Except for bark. That's the sound a dog makes.

[u/MustardEnema007 → u/nonotthat88]

I was super curious how Polyphenylene isophthalate PPPA Nomex Aramid Paper Type 410 would perform

[u/montybo2]

To anybody that plays Kerbal Space Program, this is exactly what the Science Jr Material bay is.

[u/sharty_mcstoolpants]

The 1986 Challenger Accident delayed retrieval of the Long Duration Exposure Facility (LDEF) from 11 months to 5.7 years. The tested materials were similar to the OP images.

[u/MastiffOnyx]

Just make everything out of the same stuff you made the tray of.

That thing still looks new.

[u/falcorns_balls]

They forgot to stick a mcdonald's cheeseburger out there for the control.

[u/peteschirmer]

Ooooo where is the labeled version telling us what’s what?

[u/NESpahtenJosh]

So just make everything out of the metal casing... got it.

[u/McSqueakers]

Damn all the screws were completely eroded away

[u/avocadofruitbat]

So when is NASA going to drop their sick space themed makeup pallet?

[u/Wast3edSpace]

really puts into perspective why derelict space hulks look the way they do..:)

[u/thicc_curves69]

Pretty. Looks like an eyeshadow palette

[u/Worried_Pressure_447]

Forbidden Eyeshadow Palettes

[u/HugeAnimeHonkers]

It would be cool if they also left an identical one here on earth, exposed to the elements, just to see what happens.

[u/Silly_Program_5432]

I read somewhere that if another sentient race made contact with us and discovered life on earth used highly reactive oxygen for our metabolism they would be amazed and maybe frightened kinda like us and Xenomorph acid blood.

[u/jettheblackcat]

My goodness I have so many questions but I think my top two would be 1 is there a labeled version of this somewhere to know what’s what? 2 why are some samples just gone?! Oooooh I wanna know this one so much lol

[u/FergusTheCow]

So the frame is made out of the most durable material?

[u/menjagorkarinte]

We’re they able to separate the effect of entry from space? In other words the effects of heat and speed to escape, versus stasis in space

[u/Mike_ZzZzZ → u/menjagorkarinte]

The samples were presumably retrieved and brought back inside a capsule, not exposed to reentry stressors.

[u/thecjm]

Ignore all the samples and just make spaceships out of whatever material that frame is made out of. It held up better than any of the samples

[u/Toastbuns]

I made one of the samples for one of these missions, MISSE 8 I believe!

[u/lowrads]

People that think the ISS has just been going in circles for decades don't grasp the point of laboratories.

[u/Walden_recluse]

I'll just use whatever that plate is made out of.

[u/HonestLook325]

Space is kinda racist

[u/The_last_trick]

Would be nice to have these samples labeled so we'd know what they were.

[u/anon-a-SqueekSqueek]

More interesting the longer I look at it. It's not like they all just got bleached lighter, some really reacted way different than others.

Edit: or maybe they kinda did, but definitely not at the same rate. Not quite sure.

[u/mypcrepairguy]

No twinkle, or McDonalds cheeseburger?

[u/LtHigginbottom → u/mypcrepairguy]

Twinkie Twinkie little star 💫

[u/mypcrepairguy → u/LtHigginbottom]

lol. love autocorrect sometimes

[u/TinySlavicTank]

Forbidden eyeshadow palette

[u/ellisschumann]

Surprised how well the canvas and leather held up.

[u/hchn27]

Sephora looking at this like 👁️👄👁️

[u/zzulus]

Damn, even the screws evaporated 😄😄😄

[u/guestpassonly]

Atomic oxygen is formed when short wavelength ultraviolet radiation from the Sun photodissociates molecular oxygen in the upper atmosphere. Although AO is the predominant species in LEO (below ≈1,000 km), these neutral oxygen atoms have mean free paths on the order of 104 m at 400 km, resulting in extremely low probabilities of re-association. As a spacecraft orbits the Earth it travels with a velocity on the order of 7.7 km/sec and rams into the oxygen atoms.

[u/ditty_33]

My team moves these around station with the external robotics!

[u/CatLover_42]

Important to note that the environment the ISS is in isnt the same as, for example, the moon. The earths atmosphere reaches out to the ISS and beyond, which is why it is important to know the effects of oxidation in low earth orbit.

[u/-Tom-]

I have done some atomic oxygen testing with carbon. Under an electron microscope it looks like a ton of small BB bites or pits taken out of the face. Basically atomic oxygen hits the carbon fiber and yoinks individual atoms out which leads to the pitting.

[u/LegPossible9950]

Teflon for the win

[u/Corvidae5Creation5]

You can tell which bits got pummeled by frozen turds in orbit

[u/HCRanchuw]

I’m starting to think maybe space is kind of a harsh environment you guys.

[u/SaberToothMC]

I really thought this was eyeshadow for a minute

[u/not_the_porn_alt]

So what did we learn lol

[u/shinelightbox]

Is this basically proves Elon trying to build servers in space is total bs. Because almost all the materials will have erosion.

[u/catxracoon]

cursed eyeshadow palette

[u/DarkPolumbo]

so did those 5 blanks just get clogged with space goop then?

[u/beck_is_back]

Would be more r/Damnthatsinteresting if they'd remember to label them!

[u/nichpumba]

heres some more details on this https://ntrs.nasa.gov/api/citations/20070002707/downloads/20070002707.pdf

[u/Mike_ZzZzZ]

To all the people complaining about the lack of labels: do you think a piece of tape and a sharpie would last 4 years in space? (It really isn't hard to map a simple grid on a separate document)

[u/_Kelly_A_]

Top row, fourth from the right is the Twinkie

[u/Bannon9k]

Connect 4, I win!

[u/mbashs]

What were the materials is what I am curious about.

[u/Consistent-Koala-339]

the aluminium or steel plate they attached them to appears to be the best candidate

[u/_okbrb]

So I mean, this is an atomic oxygen experiment, technically they’re testing these samples for exposure to the upper atmosphere, where the ISS hangs out

[u/mcringleberry87]

I got to test some of these samples in my undergrad!!!! They got very brittle and weak

[u/Conscious_Joke_2464]

It’s interesting that some of the preflight samples were empty and then had contents 4 years later, such as a few on the bottom row. I assume that’s space debris.

[u/DiscoBanane → u/Conscious_Joke_2464]

I'm not sure they were empty, could be just a black polymer.

[u/diminutivesweaterguy]

How did the Flex Seal hold up?

[u/Whippity]

Similar to materials tests I’ve done for commercial products but this is next level insanely cool. Looks like some materials have eroded completely leaving an adhesive sticker, or did they just fall off? I think someone linked a report in the thread somewhere.

[u/JacoRamone]

That’s my wife’s eye shadow palette