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damn i thought venus was like the moon but red. still i feel like its hard to get excited about stuff without humans intimately involved. ultimately its all abo

damn i thought venus was like the moon but red. still i feel like its hard to get excited about stuff without humans intimately involved. ultimately its all about the meatbag, he needs to be there somehow. maybe in orbit controlling the sat via FPV goggles?

theoreticalmal 1y ago
Oh boy this is all mixed up. Mars is red, are you thinking of Mars. Venus is the opposite direction to us from Mars
- voidUpdate 1y ago
  Sending a dudebro to mars would be much easier I think. It's still cold and you'd need a specialised quadbike (electric?), but seeing as martian travel is on the cards for some point in the future, you might see martian quadbike racing in your lifetime. However there are still the same food/water/oxygen issues, since it's a 9 month trip each way
  - hermitcrab 1y ago
    >Sending a dudebro to mars would be much easier I think. Indeed. The very low pressure on Mars (0.006 Bar) would be much easier to deal with than the absolutely crushing pressure on Venus (92 Bar) - not to mention the 470C surface temperature. Hanggliding or ballooning in the cloud tops of Venus would be more practical than going to the surface.
    - Sanzig 1y ago
      Humans have already survived simulated dives in hyperbaric chambers to around 70 bar with no long term effects, so in theory you may be able to have Venusian astronauts live in a habitat at ambient pressure if 90 bar is similarly tolerable (obviously would still need heroic measures for cooling, an approx. 200 K temperature differential is no joke). Getting enough gas there to pressurize the hab could be difficult, the deep dive experiments used a hydrogen/helium/oxygen mixture and I doubt you can recover helium through in situ resource extraction. And you would need some sort of acclimatization system to get the astronauts from their half-bar or so transit environment down to the surface - maybe a balloon that slowly descends over the period of a few days. So yeah, pretty much science fiction for now!
      - hermitcrab 1y ago
        >200 K temperature differential is no joke It would be more like +450K/C difference (470C, not 470K). Also it is one thing to get a person to 70 Bar in experimental conditions. It is another to actually stay at that pressure for prolonged periods and do anything useful.
        Sanzig 1y ago
        Ah, whoops, you're right! Somehow my brain defaulted to Kelvin. So 740 K down to 290 K. Carnot COP alone is only around 65%, you'll be lucky to do half that, you need the stuff outside to survive heat and sulfuric acid, and you'll need to power it somehow. You could run it off a nuclear reactor, but your reactor will not be very efficient since it has to sink heat at over 700 K. > Also it is one thing to get a person to 70 Bar in experimental conditions. It is another to actually stay at that pressure for prolonged periods and do anything useful. Fully agreed - you'd have to test this long term in a hyperbaric habitat on Earth. You may end up needing some sort of medical or pharmaceutical intervention to make it possible. Very risky. Even firmer in the realm of science fiction. It'd be a good hard sci-fi novel though.
        voidUpdate 1y ago
        It might be possible to make a hard suit where the inside is around 35 bar, which should be easier to work in (if maybe still uncomfortable), and reduce the stress on the suit of a 70 bar difference
        hermitcrab 1y ago
        Newtsuits have apparently been tested to 90 Bar: https://en.wikipedia.org/wiki/Newtsuit https://en.wikipedia.org/wiki/Newtsuit I believe they maintain ~1 Bar inside. Not sure if something like that could be built to protect a fragile human from the temperature differential, though. Better to send a robot?
        1y ago
    - johnisgood 1y ago
      I mean yeah, what can we do about that surface temperature? That is extremely high.
      - voidUpdate 1y ago
        Refrigeration is hard but I don't think impossible at high ambient temperatures. What immediately comes to mind is compressing gas (which will increase its temperature), letting it equalise with the ambient temperature, then decompressing it, which will lower the temperature (from Charles' Law). No doubt there are many other systems that could be used though. I'm not an expert on refrigeration at all, but if you're interested, it might be worth checking out the youtube channel Hyperspace Pirate, who does a lot of diy refrigeration systems, and I believe has managed to make liquid nitrogen in his garage using a home made refrigeration system. He also goes very in-depth into the technical details
        johnisgood 1y ago
        Interesting, thank you!
- hermitcrab 1y ago
  >Venus is the opposite direction to us from Mars Depends where they are in their orbits.

theoreticalmal 1y ago

Oh boy this is all mixed up. Mars is red, are you thinking of Mars. Venus is the opposite direction to us from Mars

voidUpdate 1y ago
Sending a dudebro to mars would be much easier I think. It's still cold and you'd need a specialised quadbike (electric?), but seeing as martian travel is on the cards for some point in the future, you might see martian quadbike racing in your lifetime. However there are still the same food/water/oxygen issues, since it's a 9 month trip each way
- hermitcrab 1y ago
  >Sending a dudebro to mars would be much easier I think. Indeed. The very low pressure on Mars (0.006 Bar) would be much easier to deal with than the absolutely crushing pressure on Venus (92 Bar) - not to mention the 470C surface temperature. Hanggliding or ballooning in the cloud tops of Venus would be more practical than going to the surface.
  - Sanzig 1y ago
    Humans have already survived simulated dives in hyperbaric chambers to around 70 bar with no long term effects, so in theory you may be able to have Venusian astronauts live in a habitat at ambient pressure if 90 bar is similarly tolerable (obviously would still need heroic measures for cooling, an approx. 200 K temperature differential is no joke). Getting enough gas there to pressurize the hab could be difficult, the deep dive experiments used a hydrogen/helium/oxygen mixture and I doubt you can recover helium through in situ resource extraction. And you would need some sort of acclimatization system to get the astronauts from their half-bar or so transit environment down to the surface - maybe a balloon that slowly descends over the period of a few days. So yeah, pretty much science fiction for now!
    - hermitcrab 1y ago
      >200 K temperature differential is no joke It would be more like +450K/C difference (470C, not 470K). Also it is one thing to get a person to 70 Bar in experimental conditions. It is another to actually stay at that pressure for prolonged periods and do anything useful.
      - Sanzig 1y ago
        Ah, whoops, you're right! Somehow my brain defaulted to Kelvin. So 740 K down to 290 K. Carnot COP alone is only around 65%, you'll be lucky to do half that, you need the stuff outside to survive heat and sulfuric acid, and you'll need to power it somehow. You could run it off a nuclear reactor, but your reactor will not be very efficient since it has to sink heat at over 700 K. > Also it is one thing to get a person to 70 Bar in experimental conditions. It is another to actually stay at that pressure for prolonged periods and do anything useful. Fully agreed - you'd have to test this long term in a hyperbaric habitat on Earth. You may end up needing some sort of medical or pharmaceutical intervention to make it possible. Very risky. Even firmer in the realm of science fiction. It'd be a good hard sci-fi novel though.
        voidUpdate 1y ago
        It might be possible to make a hard suit where the inside is around 35 bar, which should be easier to work in (if maybe still uncomfortable), and reduce the stress on the suit of a 70 bar difference
        hermitcrab 1y ago
        Newtsuits have apparently been tested to 90 Bar: https://en.wikipedia.org/wiki/Newtsuit https://en.wikipedia.org/wiki/Newtsuit I believe they maintain ~1 Bar inside. Not sure if something like that could be built to protect a fragile human from the temperature differential, though. Better to send a robot?
        1y ago
  - johnisgood 1y ago
    I mean yeah, what can we do about that surface temperature? That is extremely high.
    - voidUpdate 1y ago
      Refrigeration is hard but I don't think impossible at high ambient temperatures. What immediately comes to mind is compressing gas (which will increase its temperature), letting it equalise with the ambient temperature, then decompressing it, which will lower the temperature (from Charles' Law). No doubt there are many other systems that could be used though. I'm not an expert on refrigeration at all, but if you're interested, it might be worth checking out the youtube channel Hyperspace Pirate, who does a lot of diy refrigeration systems, and I believe has managed to make liquid nitrogen in his garage using a home made refrigeration system. He also goes very in-depth into the technical details
      - johnisgood 1y ago
        Interesting, thank you!
hermitcrab 1y ago
>Venus is the opposite direction to us from Mars Depends where they are in their orbits.