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Picking up glowing hot space shuttle tiles with bare hands (2011) [video]
- deleted 7y ago[deleted]
- Supermancho 7y agoI was fortunate enough to have a presentation, when I was in Elementary School (Golden Elementary in Placentia, CA), that featured bringing in Shuttle Tiles in the 80s. They put a blowtorch to once and let us touch it, right after. It was mildly interesting for a 9 year old.
- cronix 7y agoThey came to the schools in Portland, OR, as well and did the same blowtorch demo. Loved it. Came to find out just a few years ago that my aunt, who is retired from NSA/CIA/Rand, was one of the people who translated the Soviet shuttle plans and helped discover that they were stolen from the USA. Apparently she was also involved, somehow, in every stealth program up until she retired. Exactly what she did...don't know, and she wouldn't elaborate.
- gre 7y agoI got that demo in Mississippi. They must have had a huge outreach program.
- 010101010101 7y agoThe shuttle main engines were all tested at Stennis Space Center in southern MS (the same test stands were used to test parts of the Saturn V for the Apollo missions). I got to see a bunch of the tests as a kid, it was really something - always wanted to see an actual launch, but the closet I've come is catching a glimpse of the Falcon 9 from San Francisco in 2018.
- hinkley 7y agoMeanwhile, a bunch of my classmates junior year of high school took a tour of my future alma mater and came back with stories about how the thermite demo went wrong and exploded. Later I saw black and white video of the same classroom, the thermite set the projector screen on fire ( which for some dumb reason was down at the time), the instructor panicked and pulled the screen causing it to retracted. This did not put out the fire. Unfortunately the video cuts out there. The building did not burn down, apparently, but I would have liked to have seen the full saga. I almost skipped chemistry class the day they did the thermite demo for us. Instead I sat way in the back.
- Taniwha 7y agoA teacher at my highschool did the thermite demo over a large ceramic dish, it shattered the liquid iron blob burned through the floor into the classroom below
- Hallucinaut 7y agoI have to ask, given your user name, was this in central-west Auckland in the mid-90s by any chance?
- tyingq 7y agoThe "don't touch the edges, just the corners" had me a little worried. Visitors don't always pay attention. I wonder how hot the parts you weren't supposed to touch were.
- ape4 7y agoI know, aren't the corners part of the edges
- tyingq 7y agoIt seems like he meant the central faces of the cubes...the glowing parts, to be the "edges". I thought the "edges" were the ridge lines.
- Retric 7y agoHeat is not that important in this context it’s energy transfer between the block and your skin that’s at issue. Holding onto the glowing bits may eventually cause burns, but you’re reflexes are to let go very quickly. My guess is the real risk is someone dropping and thus breaking them.
- nickthemagicman 7y agoWhat happens to all that heat energy if it's broken?
- dahfizz 7y agoMost of the cool properties of these aerogel-like materials is that they are 90%+ air. Silica also has a relatively low specific heat. So, even though the material is very hot, there is not that much heat energy. There is more heat in a cup of coffee.
- derekp7 7y agoI guess this is similar to pulling out a sheet of aluminum foil from a hot oven. It is weird that you can grab it with your bare hands.
- SoapSeller 7y agoVeritasium have a nice series[0] about Aerogel - with couple of interesting demonstrations and good explanation on how it made. [0] https://youtu.be/AeJ9q45PfD0 https://youtu.be/AeJ9q45PfD0
- hanoz 7y agoThe guide keeps saying it's because they disipate heat so quickly, but I thought it was supposed be quite the opposite?
- jansan 7y agoAnd also, dissipate to where? To the hotter parts of the material? To the air? I think he is wrong.
- balfirevic 7y agoThe outermost part dissipates heat quickly to the air which lowers it's temperature (the temperature of the outermost part, that is). In regular materials, the heat flows quickly from the center, so the temperature of the outer layer cannot drop significantly in such a short amount of time. But this material conducts heat so poorly that this doesn't happen, so the outer layer stays cool.
- jtbayly 7y agoFascinating. So it’s both: it conducts to air quickly, but to itself slowly.
- kragen 7y agoAt these temperatures, radiation is usually a much more significant heat transport mechanism than conduction or convection, so probably a substantial amount of that heat was deposited in the walls of the room and the bystanders.
- javagram 7y agoYes, i think the guide is saying it backwards. The caption of the video says “ Space Shuttle thermal tiles conduct heat so poorly that after being in a 2200 °F oven for hours, you can pick them up with your bare hands only seconds after they come out, still glowing hot” This makes sense - the tiles themselves are at 2200 degrees but are not transmitting the heat quickly to you while you touch them for a brief period of time.
- aezell 7y agoAs a kid, I was involved in NASA's Junior Astronaut program around the time of the Challenger disaster. I will never forget the presentation where they had us hold one of the heat shield tiles in our bare hands while they blasted it with a blowtorch for several minutes. It just blew my mind that such a thing was possible.
- minimuseum 7y agoThis is a great document on how the tiles were made: https://ntrs.nasa.gov/search.jsp?R=19810003644 https://ntrs.nasa.gov/search.jsp?R=19810003644 We included fragments of a flown Shuttle tile in our Fourth Edition collection. The material is crazy difficult to work with. It powders under pressure. You obviously can't use a hot wire to cut it either (ha, ha).
- pvaldes 7y agoLooks like a great material to isolate a house and save heating money. Also great for saving air conditioning bills in desertic areas. If is just silica, why is not being sold yet? NASA could have stored some slighly defective or second grade quality blocks, unfit for space shuttle but waiting for a second life.
- jcims 7y agohttps://news.ycombinator.com/item?id=22655398 https://news.ycombinator.com/item?id=22655398
- dahfizz 7y agoProducing aerogel is not easy. It's "just silica" in the same way that a diamond is "just carbon". The regular house insulation already works pretty well, and heating is not incredibly expensive. Aerogel would have to come way down in price for it to make economic sense.
- kragen 7y agoSpace shuttle insulating tiles are not made of aerogel.
- dahfizz 7y agoNot by that name, but the tiles are made of blocks of silica that are 90%+ air, which is the same thing as aerogel. https://en.m.wikipedia.org/wiki/LI-900 https://en.m.wikipedia.org/wiki/LI-900
- tecleandor 7y agoSeems like they're still very far in density. LI-900 is 144.2 kg/m³ (9 lb/ft³) and silica aerogel goes around 1,900 g/m3
- kragen 7y agoWhile the tiles do have in common with aerogel that both are comprised of amorphous silica and air, they are different in many other significant ways. LI-900 is 6% silica by volume, the rest being air; silica aerogel is typically 0.2%–0.5% silica, but has been made with densities as low as 0.1%. LI-900 is opaque; aerogel is transparent. LI-900 can be "plunged into water without damage", even when hot; some silica aerogels will simply collapse if exposed to water, while others have been treated to make them hydrophobic and will probably just break into pieces. Aerogels are usually fairly isotropic, while LI-900 is anisotropic, like felt. Aerogel is made from hydrogel by supercritical boiling — at the time of the STS design, supercritical boiling of ethanol, a process that had resulted in a number of serious industrial accidents, but nowadays of CO₂, while LI-900 is made by dispersing spun glass in water, pressing it into blocks, and sintering. So it's not the same thing at all, even though it's made from the same raw material.
- tectonic 7y agoSelf-promotion: if you find this kind of thing cool, check out our weekly technical newsletter about the space industry, https://orbitalindex.com https://orbitalindex.com. We started based on feedback from HN about a year ago.
- MajesticUnicorn 7y agoThis is really cool, thanks sharing this!
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- krick 7y agoWhy can you grab it only on the corners?
- chki 7y agoMy first guess would be less surface for contact, thus less heat transfer. But the corners are also colored differently, I'm not sure why that's the case. They probably cool down quicker?
- krick 7y agoI assumed the color difference is just that they are actually cooler, so yeah, they cool down quicker. And not just "quicker": the difference must be huge in order for it to be completely safe to grab the corners and actually dangerous to grab the faces. But why?
- blauditore 7y agoProbably because it cools down much faster there, due to higher relative surface (per mass). You can also see this simply by the difference in color.
- hnarn 7y ago> Space Shuttle thermal tiles conduct heat so poorly that (...) This is nitpicking but it seems odd to use a negative value adjective like "poorly" as if high thermal conductivity would then be "excellent", instead of just saying something neutral like "low heat conductivity". I don't know, it just struck me as odd.
- dzamie 7y agoIt's vernacular, at least. People say copper conducts electricity well, so something with low conductivity would conduct poorly
- hnarn 7y agoSure, but in the case of copper you want to conduct electricity, so it makes sense to say that it conducts it "well". In the case where you want to avoid head conduction, like when re-entering the atmosphere, you don't want heat to be conducted, so a "poor" conduction is actually "good". I thought it sounded a bit odd, but since I'm being downvoted I'm assuming not many people agree, I thought I'd just point out that I thought it was interesting and/or caused some dissonance for me at least as a reader.
- dwighttk 7y agoyou might not want copper to conduct electricity if it were conducting electricity to your body.
- hnarn 7y agoThat's my point. If you're designing a suit that should stop yourself from being electrocuted it sounds weird saying that copper has "excellent" conductivity, it's not really excellent in the context you're talking about.
- dwighttk 7y ago"Copper has excellent conductivity therefore it wouldn't be a great material to make a suit out of if you want to stop yourself from being electrocuted... You'd want a material that was an excellent insulator!"
- nateburke 7y agoCorners and edges. Psssshhhhh. TOUCH THE SIDES! TOUCH THE SIDES! TOUCH THE SIDES!
- mkchoi212 7y agoWhy does he say to pick them up by the corners and not by the edges? Is there some physics that I'm missing??
- Bud 7y agoLess surface area that you are touching, and also, you can see that the corners are cooler than the rest of the object.
- mkchoi212 7y agoYeah but why do the corners get cooler?
- Aardwolf 7y agoThis is only a guess, but, material in the corners is closer to more surface area so loses heat more quickly
- stanmancan 7y agoMore surface area?
- deleted 7y ago[deleted]
- graphpapa 7y agoIf you think of it like a bunch of cells like minesweeper, where the temperature differential is a function of #of neighbouring air cells - corners are going to cool much faster!
- akeck 7y agoAlso, from the Parker Sun probe: https://www.youtube.com/watch?v=BKinVmBoIrE https://www.youtube.com/watch?v=BKinVmBoIrE
- rkagerer 7y agoI agree with the second top comment there: The material is fine, this demonstration is hilariously bad. This demonstration could be done with a block of wood. Take a blow torch to a block of wood that size and pretty much the same result.
- stevespang 7y agoYes, 2nd that, thx for sharing, really cool !
- pvaldes 7y ago(I wonder if this ultraporous stuff could be used to make a emergency mask. It seems clear that is not easy to work with, but... Looks like a giant filter for a machine)