Contact me on matrix chat: @nikaaa:tchncs.de

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Joined 2 years ago
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Cake day: January 12th, 2024

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  • I’m pretty sure how well your hair looks (or really, how well you look overall) has more to do with your physical and (importantly) mental health than with what shampoo you’re using.

    It’s just that in the US specifically, the extremely poor mental health of many women has been so normalized that we don’t even perceive it as such anymore. It’s just that society treats women so absurdly badly, it’s not even something i can put into words anymore. And that shows.




  • humans are a virus and the earth has a fever

    now one might be tempted to say that that’s a bad thing, but in my experience you can also catch a fever when you’re really positively excited about something. and virus … well, let’s say, to me it’s not an all-negative term either. knowledge is a virus (i wish i could link to an earlier blog post of mine about this, but unfortunately i never wrote down my ideas about this). basically, knowledge spreads just like a virus, it’s immaterial, consists of information, and has the typical replication patterns of viruses, including being subject to mutation and selection.


  • the thing about an atmosphere is that it protects you from a lot of radiation. like, alpha radiation makes a significant part of the radiation hitting you in outer space, but it’s too weak to go through a sheet of paper so it’s also gonna be stopped by an atmosphere of a planet. and the same goes for beta radiation, which is also easily stopped by an atmosphere. and that’s significant because it protects you from like 99% of all (particle) radiation.

    on top of that an atmosphere replenishes volatile chemicals like CO2 and H2O all the time (or at least some volatile molecules) and that’s nice-to-have.

    Also important is the heat capacity of the atmosphere. Even if the atmosphere is thin, it makes a lot of difference. I should go about calculating the difference that mars’ atmosphere makes in terms of temperature sometimes. Like, how hot/cold would it be in the day/night if it didn’t have an atmosphere. I guess it would be more extreme, but by how much? I should look into that sometime.


  • like, i remember doing the maths a while ago and figuring out the following:

    a planet needs to be in a certain mass range (from minimum mass to maximum mass) to be attractive to long-term human setttlement.

    • the minimum mass is given because the planet can only hold an atmosphere if it has a minimum mass of around 10^23 kg because only then the gravitational potential is large enough to prevent the atmosphere from floating away.
    • also, the planet has to have less than a maximum mass, sothat a spaceship can still lift off from that planet. that’s because fuel consumption scales exponentially with planet’s mass, and if the planet’s mass is too big, basically you “hit a wall” in the fuel-over-planet-mass diagram where it simply becomes practically impossible to lift off from that planet ever again. that maximum mass is around 10^26 kg.

    it is remarkable that earth is in this narrow mass range. there’s only a handful of objects in the solar system who are in this mass range: earth, mars, venus, the 4 biggest moons of jupyter, and the biggest moon of saturn (i hope i didn’t forget anyone). that’s why i think that these objects are especially interesting for long-term human settlement.


  • fun fact: in medieval astronomy/astrology (these things were not yet distinct back then), earth was indeed “mid” as it was the middle of the planets; all other planets circled around it.

    later in early modern age, earth was “mid” again but in another sense (the planets circling around the sun was accepted by then). uranus and neptune were not yet discovered, so there were only 7 known objects (+ the moon) in the solar system: sun, mercury, venus, earth, mars, jupyter, saturn. again, earth was exactly in the middle of that order.