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Joined 1 year ago
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Cake day: June 30th, 2023

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  • So when a charge is made against a credit card, you have the option to do a “chargeback” - this is meant to be used for fraud. In this case, the argument is that Reddit fraudulently changed the terms of the program after people had already paid - being in “material breach” means they made a binding promise to provide a thing and they failed to do so. Chargebacks are really, really bad for a vendor. They lose the money, and they get a penalty fee, AND if it keeps happening the credit card processor can crank up their overall fees or even drop them as a bad customer.











  • Thermal management is a huge issue for spacecraft. In atmosphere, the bulk of cooling for things like electronics would be convective, from transferring the heat into a fluid (air/water/etc) which then moves away with the heat. In space, you don’t have a fluid for convective cooling, so your cooling is all radiative - essentially just emitting infrared energy. This is far, far less efficient - you need much more material and surface area to get the same cooling.

    Dark objects are better at radiative cooling… unfortunately, they’re also far better at absorbing radiative energy. Like the oodles of it coming out of the sun. That’s why dark objects are dark - they’re absorbing the energy. However, it also means that your thermal management is far more difficult because you’re absorbing a lot more heat. It can be worked around, but it makes the spacecraft larger and heavier, which is the antithesis of space work. So spacecraft have traditionally tried to reject as much absorbed energy as possible, which by definition makes them reflective.




  • Each instance is actually an independent site running a copy of the same source code. What’s different is that they are cross-linked, so if you are on one, you can interact with any others that are federated.

    Note that federation isn’t universal. Some instances choose not to connect to others (due to things like getting problematic users from ones with less strict review and such). I had to make a new account on here since I had been using one on Beehaw, which is a relatively stricter and more limited community, and they had unlinked lemmy.world.

    So it’s a bit more work to use, but you get the benefit that there is no single central authority who can dictate things. You can move to the same topic in another instance or start your own instance.