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The Japanese have already been concerned by this problem for a few years.

Their solution has been to develop satellites made mostly of wood, which will burn completely upon reentry.

The first such wooden satellite is planned to be launched in September. It is intended mainly for collecting data about the behavior of wood in the outer space, e.g. on wood expansion, contraction and degradation, along with internal temperature and electronic equipment performance.

An alternative to wood would be the use of synthetic polymers, but those are typically more sensitive to radiation, so more research would be needed for finding a suitable plastic and appropriate additives to decrease the radiation sensitivity.

Wood or plastic would not be suitable for ships hosting humans, because they are not hermetic, but they may be an acceptable choice for satellites with a short lifetime and with much more relaxed constraints for the composition and pressure of the internal atmosphere (which may not be needed at all, e.g. when the internally produced heat reaches the external radiant cooling surfaces through solid paths or through pipes with circulant liquid).




> Their solution has been to develop satellites made mostly of wood, which will burn completely upon reentry.

I like how the Google image search for "japan wooden satellite" (https://www.google.com/search?q=japan+wooden+satellite&udm=2) is gummed up with garbage AI generated images of satellites with wooden solar panels. This wooden Borg cube with off-kilter panels is my favorite: https://indianspacetechnology.com/wooden-satellite-lignosat-.... This one is also great: https://www.universetoday.com/161473/building-a-satellite-ou.... I guess the satellite went back in time to the Cretaceous period, where North America had an inland sea?

The future is looking bright, guys!


Without AI you'd still be looking at dozens of artists' mockups of wooden satellites because they have to put something at the top of the blog post or news article to catch viewer attention.


> Without AI you'd still be looking at dozens of artists' mockups of wooden satellites

No, that's a false equivalence. The artists' mockups wouldn't be this bad. They'd either have gotten a real photo or based their artwork on one.

Now Google Images is flooded with images generated in two minutes from half-assed prompts.

> because they have to put something at the top of the blog post or news article to catch viewer attention.

They do not. That's just a current-year web design tic, which "AI" will probably kill.


> current-year web design tic

IIUC it's more that you do it to expand the page-inches on social media so that it's more likely readers will click through to your story, because social media displays the preview banner.


When it takes actual effort to create something, you tend to think about what exactly you are creating ahead of time. Time commitment and opportunity cost mean that the resulting work is a combination of both your raw mechanical effort and critical thought (both ahead of time and during the actual work).


Seriously - have people forgotten what so much of the Internet looked liked prior to just a few years ago? That is to say, exactly the same? SEO spam, quick artist mockups, mass-generated crap.


Kagi returns basically the same result set including the AI generated slop, which is disappointing.


I'm not sure how they could do any better. AI is enabling the degradation of the public web, and that's what they search.

Pretty soon the web's going to be one big Mikkelsen Twins ebook.


Well, here's an actual photo they could have used: https://www.japantimes.co.jp/news/2024/05/29/japan/science-h...

And here is an earlier rendering from 2021: https://www.japantimes.co.jp/news/2021/12/31/national/japan-...

And it only took a simple Google search to find, from a reputable news source.


This really says it all. Theres the right thing and then 1000 signs pointing every which way saying Eat At Joe's like a bugs bunny cartoon.


Blaming AI for the current trajectory of the Internet is like blaming the Internet for the current trajectory of public discourse & trust - they're both only instruments for the real reasons.


I don't buy the whole "tools are neutral, it's the people who are good or bad" responsibility-dodge argument. It's definitely true that many tools can be used for good or bad, certainly. But the people who create a tool should consider how they expect people will use their tool, and the ease at which people can use it for bad. This is pretty much Engineering Ethics 101.


When you zoom out though, this engineering problem is a cultural and political one.

If you are designing apps in an environment of scammers and shameless grifters, the options for the societies you can build are reduced.

Focusing on the core issue of "how can we stop people from destroying nice things" is critical for society-scale engineering, as it frees ethical engineers to create more magnificent tools.

Ignoring law / politics / etc, and solely focusing on "how can I design this given presence of grifters" is muted engineering.


Nanocrystalline cellulose (NCC) could be a great constituent component of a composite material. Not only would it burn, but anything that doesn't burn and makes it to the surface is biodegradable; there's lots of stuff that eats cellulose. NCC can be formed into highly strong and rigid structural pieces, or combined with carbon fiber, fiberglass, hemp, or other fibers to create ultra strong and durable composite material.

   high mechanical strength, with a tensile modulus of approximately 150 GPa and a modulus of elasticity ranging from 18 to 50 GPa. CNCs also exhibit excellent thermal stability, undergoing gradual thermal transitions and decomposition between 150 °C and 600 °C


> Their solution has been to develop satellites made mostly of wood, which will burn completely upon reentry.

"When finishing the surface of your wooden satellite you must, of course, use an orbital sander."[1]

[1]: https://www.metafilter.com/203958/Yes-they-wood-build-a-sate...


Just don’t use a random orbital sander or you may lose your satellite.


Could just send it into the astral plane.


That would be so awesome! Reminds me of the sci-fi book “Children of Time”


From the science we do on spider silk, who knows...we could one day see a Spider(Portiid)-derived hull cladding to fit around the lumber!


Yeah, the book has thought-provoking take on evolution


Leave it to Japan to make a satellite out of wood. So cool. Their innovations in woodworking are very impressive. I’d love to see a picture.


It's an interesting effort, but the supposed issue addressed in the paper is not that aluminum does not fully burn up during reentry. It generally does, just like wood. It's that, when it does so, it releases alumina.

Maybe this is better because the vaporized wood would. not release any alumina. But you'd then have to look at the impact of wood's combustion products when introduced directly to the upper atmosphere. I'm not sure anyone has seriously studied that question.


Burning pure wood doesn’t produce anything terribly exotic. We know what most of the byproducts do because they occur naturally and we’ve already studied their effects. Namely H2O, CO2, CO, and solid carbon with traces of nitrogen and sulfur oxides, along with metallic micronutrients (at a very small scale).

We already know how the major byproducts interact, I think it would be a question of modeling what happens when we start adding them to the mesosphere. Models aren’t perfect, but it’s not like we have absolutely no idea how the components interact.


So the Hearthians' timber ships made sense after all


What about something like carbon fibre?


It is used quite a bit in the space industry already. But it is more expensive so it is usually confined to applications where you really need the weight savings, or you need something with a more controlled coefficient of thermal expansion. Thermal expansion of carbon fiber is small so you get less mismatch when you use it with things like optics or as part of solar panels.

And a common place you find carbon fiber in the space industry is actually carbon fiber skinned aluminum honeycomb panels. Very light and very stiff.

https://www.rockwestcomposites.com/shop/plates-panels-angles...


Fibreglass? I'm surprised raw material/machining cost is a significant concern when you're making satellites.


But sill wood usage does have an impact on the environment too


So does corn. In fact much of the wood used in construction in the US is grown like corn in a cornfield.


I assume you mean the high atmospheric particulate. It would be interesting to see how this compares


Everything you do does. Question is how much.




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