81–89 of 89 posts
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Orbital compute presents a pretty good physical security model as well (X-37B notwithstanding). I've often thought it would be fun to build a smallsat providing crypto functions (signatures, certificates, message passing).
There's a lot of investment and development going on in asat tech...
After watching an Elon Musk interview in front of his starship he was saying - If anyone can show us that aerospikes are the way to go then please, do it. It'll be a gift.
https://www.youtube.com/watch?v=cIQ36Kt7UVg
This other company Arca has a 25-video series starting 2 years ago about their journey to build a hydrogen/oxygen (water) areospike engine. Really worth the watch. Skip to the last videos if you want to see live engine tests.
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I think you severely underestimate the usefulness of gold in electronics.
You're ignoring the problem. The electronics industry would love it if they could gold plate every single PCB but for that to happen the price of gold would have to drop. Gold mining is probably only profitable at current gold prices so the electronics industry won't benefit from expensive space gold.
There is no reason to make this assumption.
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If you don’t think robotic tech changes anything about the core of space flight, I just don’t know what to tell you.
Okay, what it changes? I know the talking points(yes, it is cheaper but not in order of magnitude) but where's the substance here? If it's the cool videos, that could have been done in CGI too. What is the new things, the thing that is a leap forward? Sure, it is nice to end the reliance on Russia but that's a political advancement. If it's the wild stock market, you can do it with cryptocurrencies too(maybe rockets…
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If you don’t think robotic tech changes anything about the core of space flight, I just don’t know what to tell you.
Okay, what it changes? I know the talking points(yes, it is cheaper but not in order of magnitude) but where's the substance here? If it's the cool videos, that could have been done in CGI too. What is the new things, the thing that is a leap forward? Sure, it is nice to end the reliance on Russia but that's a political advancement. If it's the wild stock market, you can do it with cryptocurrencies too(maybe rockets…
I don’t know how robotics plays in here, that’s the innovation to come.
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It is not likely to survive orbit deployment, unfortunately.
Long term or short term? I don't need a century-level deployment, but I would like to see how long it would survive.
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From https://momentus.space/development/ it looks like they are using a microwave generator with water to generate a plasma thruster. The technical name seem to be microwave electro-thermal thruster (MET). There is more info on the thurster in the abstract here: https://ieeexplore.ieee.org/abstract/document/1420619
How does the specific impulse compare to the current state of the art hall effect / ion thrusters that use xenon as a fuel?
Edit- I looked at the Momentus paper linked above and apparently their ISP is 800s
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How does the specific impulse compare to the current state of the art hall effect / ion thrusters that use xenon as a fuel?
Probably worse. Raw steam has an ISP of around 100s. There was an experimental ion thruster from U Michigan a few years ago that got that up to nearly 700s. Some of the more efficient ion thrusters are like 20,000s (although they're operating at a different scale so idk if that's an apples to apples comparison) Edit- I looked at the Momentus paper linked above and apparently their ISP is 800s
Once in orbit unless you need to achieve a lot of delta-v in a relatively short period of time, I'm not sure why an engine/fuel combo with only 800 ISP would be a logical choice. It's certainly a whole lot more efficient than a bipropellant chemical rocket engine, which maxes out around 385-400 ISP. Although it's never flown I believe the theoretical efficiency of a NERVA would be around 800.