4 ms·

The Moss That Could Terraform Mars

• bell-cot 2y ago
  To do anything resembling terraforming, you'd need a whole lot more atmosphere. Moss doing this: CO2 + sunlight => O2 + more moss does nothing to change the "space suits mandatory" situation.
  • Qem 2y ago
    > To do anything resembling terraforming, you'd need a whole lot more atmosphere. Perhaps not that much. Apparently plants fare much better than animals in low pressure, withstanding down to 10kPa atmospheric pressure. See https://ntrs.nasa.gov/api/citations/20050182975/downloads/20050182975.pdf https://ntrs.nasa.gov/api/citations/20050182975/downloads/20... IIRC, there is a rule of thumb the atmospheric pressure drops by about 10% every 1100m one goes up close to earth surface. 10kPa would then be the pressure on top of a mountain rising ~24km above sea level. But I bet the moss wouldn't fare well in perchlorate soaked soil anyway.
    • bell-cot 2y ago
      > Perhaps not that much [more]. From a quick search, the atmospheric density on Mars is ~20X lower than the top of Mt. Everest - the "dying zone". (And with the lower gravity, you'd need whole lot more than 20X, to get the same atmospheric pressure on Mars.) 20X'ing even a small planet's atmosphere is a big-ass ask. And if humans can only live inside pressure suits, or pressurized habitats on Mars - then "some plants can grow on the surface" is "that's nice, but...". Hmm... Earth is much bigger than Mars, and has overheating problems. Gasses cool when they expand, per pV=nRT. In theory, if we exported a bunch of the Earth's atmosphere to Mars, we could kill 2 birds with one stone. @xkcd, you want to take this?