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Joined 1 year ago
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Cake day: March 17th, 2024

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  • It is unscientific, but let’s not pretend we here in Europe don’t sometimes do it anyway. Racism is still a thing in Europe, unfortunately. But also, it has been a thing in Europe for basically as long as humans have lived on a large enough scale to notice it. In the 19th century you had the “three great races” of “Caucasoid, Mongoloid, and Negroid”. Even way back in the time of the Roman Empire they were being weird about race, ascribing strength and aggression to the pale people to their north and intelligence and peacefulness to the darker people to their south and east.

    We’re collectively getting a lot better about not doing it these days, but we’ve got to recognise that there’s still progress needing made


  • To be honest most of the basic physics behind rocketry actually isn’t too difficult. The matter of engineering it into reality definitely is very difficult, finding fuels that burn hard enough and figuring out how to contain them while they burn and the like. The nature of going so far and so fast also means that tiny errors add up to very big problems.

    All rockets function on the fact that if you push something in one direction, you also go in the opposite direction by a proportionate amount. Lighting fuel on fire while it’s in a tube that only has one way out just happens to be a great way to push the burning fuel really, really hard and therefore get a really hard push back. The forces involved always have to cancel out the total momentum of everything involved; you chuck X kilograms of burning fuel out of the back at Y metres per second, you accelerate forward by however much you need to to make your momentum match that in the opposite direction. This is Newton’s third law of motion, the “for each action there is an equal and opposite reaction” one

    Nozzles and the like can adjust which direction the way out is pointing. If the way out points left a bit, the momentum of the fuel is also going left a bit, so the reaction momentum you get goes a bit to the right, and now you have steering

    I think the biggest conceptual block people usually have about orbits is that they’re not about going up fast, they’re about going around the Earth fast. If you point your rocket straight up and just keep going straight up, you won’t go into orbit around the Earth. Either you’ll crash straight back down when you run out of fuel, or you have a rocket with enough power and fuel to reach Earth’s escape velocity, in which case you’ll just continue travelling away from Earth forever until you find something else’s gravity. You know the kind of arc that a ball has when you throw it? Imagine that you’re superhumanly strong and can throw a ball literally however hard you want. You could throw it beyond the horizon without breaking a sweat. Once you’re throwing it that hard, the curvature of the Earth starts to become relevant, right? The ground is effectively dropping away underneath the ball as it travels forward, letting it fly farther before it hits the ground. Eventually if you throw hard enough, the curvature of the Earth turns away from the ball at the same rate as the ball is falling. The ball is now in orbit. The ISS (and anything else that wants to orbit at the same altitude) goes around the Earth so fast that it does 15 entire laps around the planet every day

    Unfortunately for our rockets, the Earth’s atmosphere is very bad to actually move through that fast, so they go up first to get out of the thickest part of the atmosphere and then gradually turn sideways to achieve orbit

    Once you start getting into things like how to get from Earth to other planets you’ve got to worry about some other stuff, but this comment is probably getting long enough by now and not many of our rockets do that yet

    I totally get what you mean about planes not looking like they should work. The size of them and the fact that we’ve got basically nothing to reference them against for scale and motion when they’re in the air is really confusing



  • It’s about as close to a random person as you can get while still being recorded. They were royalty, but the two real ones get literally a sentence each at max

    • Eithne ingen Bresail Bregh married the king of Tara and is described as “having deserved reward from God for her good works, and for her intense penance for her sins” in one source and “deserved to obtain the heavenly kingdom, having done penance” in the other
    • Eithne ingen Cinadhon was the daughter of a Pictish king and is literally only recorded as having died
    • The legendary Eithne is the daughter of a king of Scotland (mostly Pictish at the time) and crossed the sea to Ireland, where she gave birth to the hero Túathal Techtmar. This is the entirety of her role in the story; a couple of paragraphs in a collection that, in the translation I’m looking at, has 600 pages just for part five

  • Not sure if I can call this knowledge since I don’t know if it’s true, but I think I identified a couple of women from the 8th century CE who are mentioned in some Irish annals as actually being the same person. As far as I know there’s next to no discussion of these women on the internet and there are basically no historical records of them, at least. So I guess if I’m right it’s very obscure?

    The women in question are Eithne ingen Bresail Bregh and Eithne ingen Cinadhon (and possibly also the legendary Eithne mother of Tuathal Techtmar)












  • Any resort, frankly. I remember a conversation with a colleague a while back about holidays. I said I’d like to see Turkiye, and they mentioned that they had been the year before - to a resort at Antalya that they never left the entire time. Now, each to their own, if that’s what makes you happy on holiday then do that. But to me personally? That sounds bloody miserable. That sounds like you didn’t see the country at all. Why go o another country to only stay at a resort trying to cordon you off from the country? If I go to Turkiye I want to see the Roman and Ottoman heritage of Istanbul, or try all the Turkish coffee, or see the rock-cut towns and balloon festivals in Cappadocia, or visit Gobekli Tepe. You know, stuff I can only experience in Turkiye



  • You’ve got the details a little wrong. The original two were the Whigs and the Tories, as you say. The Whigs became the Liberals who became the modern day Liberal Democrats, who still exist but haven’t been in power outside of being a junior member of a coalition for a century. Tories became the Conservatives, who are still one of the major two and are regularly still called the Tories. There was a faction that broke away from the Whigs called the Liberal Unionists, who merged into the Conservatives, but they’re separate from the Liberals. Labour is not a successor to either of them, though they did make some strategic agreements with the Liberals early on. In the early 1900s, Labour replaced the Liberals as one of the two major parties.

    It is still consistently a two-party system. One of the historic parties got replaced and there is a stronger presence for minor parties than there is in the states (see especially the SNP in the past decade and the Tory-LibDem coalition in 2010), but still a two-party system