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Joined 2 年前
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Cake day: 2023年10月6日

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  • I would think that ripping 1000L of water out of an environment in a day is going to have more immediate impacts than you eventually pissing on a cactus is going to fix…

    Well… It all depends on what you do with the water. Are you sequestering it in some way or are you releasing it? I mean, if the community drank 1000 liters of water, then their next piss is 100% going to fix it. Even watering crops is just releasing the water.

    just as damaging as removing 1000L of water a day from a lake and thinking the ecosystem will be fine because you’re going to sweat next to the dry lakebed.

    Again, if you’re going to sweat 1000 liters, then go for it, I fully endorse this plan. Use as much water as you want, it’s fine unless you’re shipping it out.



  • However we do come back to Fermi’s Paradox: the universe is 13800million years old. So far we have no evidence a probe has reached our star system. Where are they? Maybe we just haven’t stumbled across one yet. Or maybe life really is very rare?

    Well there are actually some pretty convincing explanations for for the Fermi Paradox. The one I like most is that despite the 13800 million years, we’re pretty early for complex life, and we may just be the first technological civilization in the Milky Way.

    The theory goes that while there are a lot of older stars out there, there aren’t a lot of 3rd generation stars. When some stars get to the end of their life, they collapse and then go supernova, leaving behind a dust cloud in which other stars can then form. Here’s the thing, many heavy elements are only produced through nuclear fusion during a supernova. (Basically everything heavier than iron, about 3/4 of the periodic table). So that second generation of stars contain more heavy elements within the star. When the second generation goes supernova, more heavy elements are created.

    Life exists on earth thanks to all of the complex chemical reactions that can take place on earth. But all that may only be possible because we’re a 3rd generation solar system with all our fancy heavy elements, and 3rd Gen star systems are relatively new, we’re quite early on the scene.

    So because of that, we’re certainly an early civilization, and we might be… the first.


  • And even if they could, it’s hard to imagine a reason to travel to another star system.

    The expansion of a species beyond a single star system for any reason is dubious, there’s really just no reason to do it, and the cost is extremely high (given known physics).

    I say there’s no reason to leave the solar system, but I think that probably needs some explanation, because the obvious reason that may come to mind is probably overpopulation on earth and looking for other habitable planets. The thing is, in order to travel to another star system you need to really master surviving in space; if you can build a colony ship, you can build space habitats. But if you can build space habitats, then you have enough material and energy right here in the Sol system to support quadrillions of humans living in space habitats. In other words, there’s no reason to leave for tens of thousands of years.

    All that is to say, if you aren’t traveling to other star systems for your own species, you probably aren’t doing it for others.


  • I mean… whenever a price is dropping, that’s beating the odds, and your scoffing at a 95% price drop? We’ve had our first forays into reusable rockets, preserving booster stages, occasionally fairings. But when we have fully reusable rockets, from competing providers and in different payload size ranges, then it’s a whole different ballgame.

    But I guess to your point, we’re probably looking at another 95% price drop over 25 years. (But who knows, maybe just 10-15)

    Still, I think that is extremely significant!