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Cake day: 2026年11月8日

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  • Any gas cloud of sufficient mass would eventually collapse into a single spherical object. A star, if large enough to support fusion in the core, or a planet if not large enough. This ‘internal pressure drives the gas apart’ theory doesn’t hold water – if this was true, all the gas giants would instantly burst out into a diffuse cloud of gas, and the sun would be even worse, driven apart by gas pressure and the energy of fusion in the core. If the gas cloud has enough collective mass to form a planet or star, that collective mass is enough to overcome gas pressure.

    Now, gas pressure would still push back as the gas tries to condense around the center of mass, so it wouldn’t collapse instantly. And if the system has any angular momentum, it will form a disk first, which would then slowly collapse into a spherical shape due to friction/gravitational effects gradually slowing the speed of rotation and causing gas to fall inward.

    Where your theory might have some merit is when it comes to planets forming around a new star. If the cloud of gas is more or less homogeneous, why wouldn’t all of it eventually collapse into the center? But if some ‘seed’ nodule of denser material enters into orbit through the cloud, that object would then start accumulating gas around itself, which then increases its mass and draws in more gas, and so on. Everything outside that object’s orbit around the proto-star would tend to collide and be ‘eaten’ by the proto-planet before it could fall inward far enough to reach the star itself.

    So, in other words, I think you may have something when it comes to planet formation, but not star formation. A cloud of hydrogen/helium gas doesn’t need any ‘core’ to gather around in order to form a star – it will just gather around the collective center of mass. We already know the early universe contained only hydrogen, helium, and a tiny bit of lithium. The very first stars, at least, had to form without any dense core to start with. But dense ‘seed’ cores might be required in order to form planets around a star in cases when they all form together. (Though ‘rogue planets’ far away from any star’s influence could still form without needing any sort of denser core. And those rogue planets could later be captured into orbit around a star, so it could still be possible to find a core-less planet in orbit around a star.)



  • The risk tends to be hugely overblown.

    1: Use a VPN so your ISP can’t tattle on you for downloading things.

    2: Virus scan stuff you download before opening/running it.

    3: Keep good backups (you should be doing this anyway) so you can restore from backup if some kind of virus/malware manages to evade your virus scan.

    Do those three things, and the risk of downloading pirated shit will be incredibly low. (And streaming isn’t zero-risk, either. The streaming apps or the streaming files themselves could theoretically be compromised, after all.)








  • Oh, hands or ‘hands high (hh)’ is a very fun obscure unit of measure. It is only used for measuring the height of horses … and nothing else.

    One hand is 4 inches, and the number after the decimal is additional inches above the last 4 measured. So 10.0hh, 10.1hh, 10.2hh, and 10.3hh are all valid measurements, but 10.4hh is just 11hh, and 10.5hh or higher is complete nonsense. And since horses might raise or lower their heads in varying degrees at any time, making it very difficult to get a consistent measurement, the measurement is always taken at the point of the withers (shoulders) – basically the highest point on a horse’s back, at the base of their neck – because that measurement doesn’t change much depending on how the horse moves. If you want to be really precise about the measurement, it should be taken while the horse is standing still with all four hooves standing squarely and flat on level ground.

    And, yes, it actually is still in common use whenever people talk about the size of a horse.





  • I’m not seeing a situation were being hacked would require a tent or gas mask.

    But if the chemical plant near you gets hacked, then you might be grateful to have a gas mask…

    But that kind of thing is highly dependent on location and your own personal risk profile. Personally, I do have gas masks for me and my girlfriend (old Polish military surplus that’s compatible with NATO filters, only about $30 each), but those are much more likely to be used for rioting/protesting than for emergency preparedness. Immunity to teargas and pepper spray sure is nice…

    (Though, actually, I did use it once in an emergency. A small kitchen fire started while we were on a walk. Put it out pretty easily with a fire extinguisher when we came back, but it was a pretty nasty smoky fire and filled the house with toxic-smelling smoke. We had two cats inside that I wanted to rescue, so I put on my gas mask to help find them. Once I found the gas mask and got it on, it was so much easier to see and breathe in the smoke. Which was good. One cat was quick and easy to find – came right to me. But the other cat had hidden in a pile of stuff in a corner and took quite a bit of effort to find – she was lethargic and weak when I finally found her, obviously suffering badly from smoke inhalation, but she recovered within a few minutes once I brought her outside into fresh air. For a couple days after that, we left all the windows open and lived in a travel trailer in the back yard instead, the cats as well. After that, the smell of smoke mostly cleared out, and we could move back in. I guess an RV in the back yard is also nice to have for emergency preparedness – it’s kind of an entire backup house when you need one.)