• Saigonauticon@voltage.vn
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    1 year ago

    So, in the fine tradition of using bananas for scale…

    Bananas are slightly more radioactive than the background, due to potassium-40 content. So an informal unit of radiation measure in educational settings is the ‘banana-equivalent-dose’, which is about 0.1 microsieverts.

    My particle spectrometer saw first light today, and I figure that I could use a banana to calibrate it. Then I noticed that K-40 undergoes a rare (0.001%) decay to 40Ar, emitting a positron. So not only is a banana a decent around-the-house radioisotope source, it’s also an antimatter source.

    Truly a remarkable and versatile fruit.

  • silas@programming.devOP
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    1 year ago

    I learned recently how the James Webb Space Telescope is not orbiting around Earth but literally orbiting around an empty point in space. I don’t think I even quite understand it, but it’s really cool

  • kakes@sh.itjust.works
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    1 year ago

    Just watched a Tibees video about the possibility of a force like gravity potentially traveling through folded 4D space and affecting something before the light can reach it.

    I realize this sort of thing has been thoroughly tested and debunked, but I can’t get it out of my head. What if it’s some force other than gravity? What if Earth just happens to be folded against some empty bit of space - and what if that were to change?

    Like, I’ve thought about folded spacetime before, but always in the context of traveling between points (like the classic ant-on-paper thought experiment). I never really considered that something could in theory radiate a force (like gravity) in 4+ dimensions.