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Potentially dumb question, but I keep reading that the average surface temperature of Venus is 450C and so completely hostile to life, but didn't we discover re

Potentially dumb question, but I keep reading that the average surface temperature of Venus is 450C and so completely hostile to life, but didn't we discover recently that the poles are much colder? [1] Aren't there thus regions on the surface with similar temperatures to earth? [1] https://astronomy.com/news/2016/04/esa-finds-a-frigid-surprise-hiding-at-venus-poles https://astronomy.com/news/2016/04/esa-finds-a-frigid-surpri...

rm445 6y ago
The polar _atmosphere_ is colder than expected[1]. According to Wikipedia, the coldest point on the surface is 380 degrees C. https://sci.esa.int/web/venus-express/-/57735-venus-express-swansong-experiment-sheds-light-on-venus-polar-atmosphere https://sci.esa.int/web/venus-express/-/57735-venus-express-...
- rowanseymour 6y ago
  Ah ok that makes more sense... 380C is still pretty toasty.
  - kavi87 6y ago
    It's 2 or 3 times what we use for "sterilization", if there's life it really loves the extreme
    - gowld 6y ago
      That's not quite how degree-based scales work. In Kelvin we see it's about 1.5x as hot. Or if you look at distance from "comfy" (25 C) to "dead" it's about 3x as far as dead from comfy so the conclusion still works .
      - sergeykish 6y ago
        I think the comparison was to 0..100C - liquid water on Earth surface. Boiling point depends on atmospheric pressure. On Venus (93 bar) melting point is about 0C [1] and it boils at 305.6C. Interestingly under pressure "water becomes less polar and behaves more like an organic solvent such as methanol or ethanol" [2]. [1] https://en.wikipedia.org/wiki/Pressure_melting_point https://en.wikipedia.org/wiki/Pressure_melting_point [2] https://en.wikipedia.org/wiki/Superheated_water https://en.wikipedia.org/wiki/Superheated_water
deleted 6y ago
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typicalbender 6y ago
The other place where life could exist is in the upper atmosphere where apparently temperatures are much more hospitable. There's a really good write-up with more information here [1]. On earth there exists microorganisms that live in our atmosphere so one hypothesis to explain the phosphine is that there may be a similar situation on Venus. I believe its also been theorized that we could build floating cities on Venus [2] given the climate in the upper-middle atmosphere. [1]: https://www.reddit.com/r/Andromeda321/comments/ismnrb/venus_has_phosphine_in_its_atmosphere_what_does/ https://www.reddit.com/r/Andromeda321/comments/ismnrb/venus_... [2]: https://en.wikipedia.org/wiki/Colonization_of_Venus https://en.wikipedia.org/wiki/Colonization_of_Venus
- JohnJamesRambo 6y ago
  I assume the atmosphere microorganisms on Earth started in a terrestrial tidal pool though and evolved from there. There’s the rub for thinking about atmosphere organisms existing on other planets.
  - ch4s3 6y ago
    Venus in the distant past had hospitable surface temperatures.
    - JohnJamesRambo 6y ago
      Oh I did not think about that or know that. That’s true. “Recent studies from September 2019 concluded that Venus may have had surface water and a habitable condition for around 3 billion years and may have been in this condition until 700 to 750 million years ago.”
      - AnIdiotOnTheNet 6y ago
        It is interesting that this timeline lines up roughly with the appearance of plant and animal life on earth.
      - sergeykish 6y ago
gostsamo 6y ago
You still have to consider 90 times the air pressure and the acid rains.
- deleted 6y ago
  [deleted]
- kavi87 6y ago
  That plus the ~500°C at the surface and we have a little paradise to explore
DamnInteresting 6y ago
To the best of our understanding, the surface of Venus is isothermal, meaning that there is little variability in temperature, whether on the pole or equator, day or night. That 2016 rash of articles about "cold poles" on Venus were rather misleading interpretations of a single scientific paper about a measurement from the upper atmosphere.

rm445 6y ago

The polar _atmosphere_ is colder than expected[1]. According to Wikipedia, the coldest point on the surface is 380 degrees C. https://sci.esa.int/web/venus-express/-/57735-venus-express-swansong-experiment-sheds-light-on-venus-polar-atmosphere https://sci.esa.int/web/venus-express/-/57735-venus-express-...

rowanseymour 6y ago
Ah ok that makes more sense... 380C is still pretty toasty.
- kavi87 6y ago
  It's 2 or 3 times what we use for "sterilization", if there's life it really loves the extreme
  - gowld 6y ago
    That's not quite how degree-based scales work. In Kelvin we see it's about 1.5x as hot. Or if you look at distance from "comfy" (25 C) to "dead" it's about 3x as far as dead from comfy so the conclusion still works .
    - sergeykish 6y ago
      I think the comparison was to 0..100C - liquid water on Earth surface. Boiling point depends on atmospheric pressure. On Venus (93 bar) melting point is about 0C [1] and it boils at 305.6C. Interestingly under pressure "water becomes less polar and behaves more like an organic solvent such as methanol or ethanol" [2]. [1] https://en.wikipedia.org/wiki/Pressure_melting_point https://en.wikipedia.org/wiki/Pressure_melting_point [2] https://en.wikipedia.org/wiki/Superheated_water https://en.wikipedia.org/wiki/Superheated_water

deleted 6y ago

[deleted]

typicalbender 6y ago

The other place where life could exist is in the upper atmosphere where apparently temperatures are much more hospitable. There's a really good write-up with more information here [1]. On earth there exists microorganisms that live in our atmosphere so one hypothesis to explain the phosphine is that there may be a similar situation on Venus. I believe its also been theorized that we could build floating cities on Venus [2] given the climate in the upper-middle atmosphere. [1]: https://www.reddit.com/r/Andromeda321/comments/ismnrb/venus_has_phosphine_in_its_atmosphere_what_does/ https://www.reddit.com/r/Andromeda321/comments/ismnrb/venus_... [2]: https://en.wikipedia.org/wiki/Colonization_of_Venus https://en.wikipedia.org/wiki/Colonization_of_Venus

JohnJamesRambo 6y ago
I assume the atmosphere microorganisms on Earth started in a terrestrial tidal pool though and evolved from there. There’s the rub for thinking about atmosphere organisms existing on other planets.
- ch4s3 6y ago
  Venus in the distant past had hospitable surface temperatures.
  - JohnJamesRambo 6y ago
    Oh I did not think about that or know that. That’s true. “Recent studies from September 2019 concluded that Venus may have had surface water and a habitable condition for around 3 billion years and may have been in this condition until 700 to 750 million years ago.”
    - AnIdiotOnTheNet 6y ago
      It is interesting that this timeline lines up roughly with the appearance of plant and animal life on earth.
    - sergeykish 6y ago

gostsamo 6y ago

You still have to consider 90 times the air pressure and the acid rains.

deleted 6y ago
[deleted]
kavi87 6y ago
That plus the ~500°C at the surface and we have a little paradise to explore

DamnInteresting 6y ago

To the best of our understanding, the surface of Venus is isothermal, meaning that there is little variability in temperature, whether on the pole or equator, day or night. That 2016 rash of articles about "cold poles" on Venus were rather misleading interpretations of a single scientific paper about a measurement from the upper atmosphere.