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Joined 1 year ago
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Cake day: August 6th, 2023

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  • Accepting ssh key fingerprints on first ssh is a bad practice. Ssh ca’s and or sshfp are around and have been for decades. Accepting random host keys is like trusting random self signed ssl certificates.

    Use ssh ca’s for user and host keys so you can revoke and rekey hosts without having to update authorized keys. And then you can revoke access to hosts for users as well and much more.


  • mitchty@lemmy.sdf.orgtoScience Memes@mander.xyzapep
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    6 months ago

    Not without an inappropriate amount of delta v, it takes effort to hit the sun from the earth. Iirc it’s less energy to yeet yourself out of the solar system from earth than to hit the sun. Direct be even crazier amounts of energy to cancel out our orbital velocity. Iirc it would be easier to do a Jupiter transfer to save on delta v, going direct though is clown town energy waste unless you have some dying need to get there faster for some reason. But you’ll pay for it, a lot, least until we get warp drives or something neato exotic. https://issfd.org/ISSFD_2014/ISSFD24_Paper_S6-5_jehn.pdf If you’re willing to trade time there are less costly ways to “hit” a 700 000 km radius target energy wise.






  • I’d say still too soon to say. It’s a very touchy process to maintain so my guess is we would see this in rockets and probably large turbines used for power at first then likely ships and probably filtering down as we improve. Best bet on this is to expect it in a 10 year horizon from where it’s at. The fact we can run as long as this test did in only about 3ish years of development? Is a good sign. Honestly rotating detonation engines working at all is a minor engineering miracle so even just a working rocket engine is huge. This can help the rocket equation a ton depending on how far from theoretical we get in reality but let’s swag 20%, that is better than the 10% we gained from switching from an open cycle to closed cycle rocket engine.

    Fun times ahead though!