5 ms·
The challenge is that Earth's air isn't dense enough. That said, the math is "easy" density is volume/mass, vacuum adds no mass, so it is just material mass / v
by ChuckMcM 6y ago
The challenge is that Earth's air isn't dense enough. That said, the math is "easy" density is volume/mass, vacuum adds no mass, so it is just material mass / volume.
A 20cm diameter diamond sphere that was .5mm thick would have a mass of about 41g, a 20cm diameter sphere of air at sea level and "room" temperature is about 50g. So you would get 9g of "lifting force" from such a balloon (assuming I did all the calculations correctly). And experience about 2,900lbs of compression force.
Any air in the sphere would add weight.
- bananasbandanas 6y agoIf you're interested in some fiction with this concept: In Neal Stephenson's 'Diamond Age' humans have mastered assembly of individual atoms in basically arbitrary ways. They use it (among other things) to create flying airships with an envelope made of diamond with a vacuum inside. Found it to be a fun read in general.
- gibspaulding 6y agoI've really enjoyed several of Stephenson's books, but 'Diamond Age' was one I couldn't get into. I need to give it another shot. On the subject of Sci-Fi, there's also a vacuum airship featured in one of Edgar Rice Burroughs' Tarzan novels - 'Tarzan at the Earth's Core'. It is of course much less scientific than Stephenson's version though.
- rtkwe 6y agoHe really likes to drop readers in with minimal explanation into a world, he's gotten much better at it over time but Diamond Age is both one of his earlier works and one of his most esoteric worlds with the odd neo-Victorians etc.
- rtkwe 6y agoThat's always a fun blast from the tech hype past where nanotechnology was going to be pure magic with tiny machines capable of doing anything. That was an exciting possible future while it lasted, nanotechnology is doing neat stuff but it's nowhere close to the wild promises.
- mojomark 6y agoI too always thought the field of clatreonics (1) would be further along by now. 1. https://en.wikipedia.org/wiki/Claytronics https://en.wikipedia.org/wiki/Claytronics
- rtkwe 6y agoYeah we're starting to do that but the individual pieces are pretty large and I think we're much more level headed about how small they can be shrunk now.