5 ms·

At 1/100 distance, wouldn't a hypothetical planet be tidally locked to the white dwarf? Could tidally locked planets be suitable for life?

cenamus 2y ago
Not quite that close but Mercury seems to have an interesting interaction with the sun https://en.m.wikipedia.org/wiki/Mercury_(planet)#Spin-orbit_resonance https://en.m.wikipedia.org/wiki/Mercury_(planet)#Spin-orbit_...
A_D_E_P_T 2y ago
> At 1/100 distance, wouldn't a hypothetical planet be tidally locked to the white dwarf? Probably. Well, usually. If something gave that planet a very hard knock, it could spin up for a while, especially if it's around the outer limits of the proposed habitable zone. > Could tidally locked planets be suitable for life? Definitely. Depends how well they're able to redistribute heat from the hot side to the dark side. So atmospheric composition and water content (also the presence and extent of surface water) would be the decisive factors. You'd get wild weather, though.
- 867-5309 2y ago
  it's a hard knock white dwarf dust
  - Loughla 2y ago
    That's almost a joke. I don't know what to categorize that as. It isn't a pun. What is that?
    - bovermyer 2y ago
      It's technically a filk, just really short.
    - thehappypm 2y ago
      “It’s a hard knock white.. dwarf dust!” Is the joke
      - Loughla 2y ago
        Yes. I understand. I was saying it's almost a joke. But for real what is it called when the things you're saying don't necessarily rhyme with the original phrase but have a similar cadence?
        thehappypm 2y ago
        This does (nearly) rhyme
- bell-cot 2y ago
  > Definitely. Depends how well... I'm less optimistic. Between the fraction of the planet's surface that's suitable for life, the lack of tides, the (likely) lack of plate tectonics, and impairment of the various cycles ( https://en.wikipedia.org/wiki/Biogeochemical_cycle https://en.wikipedia.org/wiki/Biogeochemical_cycle ) - tidal locking to the star will profoundly degrade the planet's suitability for life. Tidal locking may also rule out having a planetary magnetic field. Though "protect the atmosphere" may not matter much, if said atmosphere (plus the water) has all condensed and frozen on the dark side of the planet.
  - mapt 2y ago
    Depending on the thickness and composition of the atmosphere, convection may be sufficient to prevent ice buildup. The thing about a tidally locked planet, and about marginally habitable planets in general, is that whatever the average, there are a wide range of surface conditions and often the spectrum is large enough that some subset of them are habitable.
    - MichaelZuo 2y ago
      Wouldn’t the entire planet experience very high winds nearly all the time?
      - deleted 2y ago
        [deleted]
  - tzs 2y ago
    Does the atmosphere need protecting? White dwarfs don’t have solar wind.
  - deleted 2y ago
    [deleted]
BurningFrog 2y ago
On a tidal locked planet, conditions should be very static. The point facing the sun is the hottest, and the opposite point is the coldest. Which means there is a constant "spectrum" of climates in between, and you only need one of these thousands of microclimates to be beneficial for creating life. So this may be the planets most suitable for life, if this theory I just made up has any validity!
- surgical_fire 2y ago
  It does make some sense, even if life would be viable only in (for example) the twilight rim of the planet (such as around the poles)
- cma 2y ago
  https://en.wikipedia.org/wiki/Eyeball_planet https://en.wikipedia.org/wiki/Eyeball_planet
rybosome 2y ago
I once read an article that speculated about this. The conclusion was that perhaps there could be a ring around the planet, at the border of the side facing the sun from the side facing away from the sun. That ring could be a habitable zone.
AnotherGoodName 2y ago
A large moon should absolutely mess this tidal locking up fwiw since it will have far more influence than the star just as our moon has far more tidal influence than our sun. Not that I think tidal locking is a blocker for life but it’s also not a big deal since large moons are extremely common and therefore the tidal locking is not guaranteed.

cenamus 2y ago

Not quite that close but Mercury seems to have an interesting interaction with the sun https://en.m.wikipedia.org/wiki/Mercury_(planet)#Spin-orbit_resonance https://en.m.wikipedia.org/wiki/Mercury_(planet)#Spin-orbit_...

A_D_E_P_T 2y ago

> At 1/100 distance, wouldn't a hypothetical planet be tidally locked to the white dwarf? Probably. Well, usually. If something gave that planet a very hard knock, it could spin up for a while, especially if it's around the outer limits of the proposed habitable zone. > Could tidally locked planets be suitable for life? Definitely. Depends how well they're able to redistribute heat from the hot side to the dark side. So atmospheric composition and water content (also the presence and extent of surface water) would be the decisive factors. You'd get wild weather, though.

867-5309 2y ago
it's a hard knock white dwarf dust
- Loughla 2y ago
  That's almost a joke. I don't know what to categorize that as. It isn't a pun. What is that?
  - bovermyer 2y ago
    It's technically a filk, just really short.
  - thehappypm 2y ago
    “It’s a hard knock white.. dwarf dust!” Is the joke
    - Loughla 2y ago
      Yes. I understand. I was saying it's almost a joke. But for real what is it called when the things you're saying don't necessarily rhyme with the original phrase but have a similar cadence?
      - thehappypm 2y ago
        This does (nearly) rhyme
bell-cot 2y ago
> Definitely. Depends how well... I'm less optimistic. Between the fraction of the planet's surface that's suitable for life, the lack of tides, the (likely) lack of plate tectonics, and impairment of the various cycles ( https://en.wikipedia.org/wiki/Biogeochemical_cycle https://en.wikipedia.org/wiki/Biogeochemical_cycle ) - tidal locking to the star will profoundly degrade the planet's suitability for life. Tidal locking may also rule out having a planetary magnetic field. Though "protect the atmosphere" may not matter much, if said atmosphere (plus the water) has all condensed and frozen on the dark side of the planet.
- mapt 2y ago
  Depending on the thickness and composition of the atmosphere, convection may be sufficient to prevent ice buildup. The thing about a tidally locked planet, and about marginally habitable planets in general, is that whatever the average, there are a wide range of surface conditions and often the spectrum is large enough that some subset of them are habitable.
  - MichaelZuo 2y ago
    Wouldn’t the entire planet experience very high winds nearly all the time?
    - deleted 2y ago
      [deleted]
- tzs 2y ago
  Does the atmosphere need protecting? White dwarfs don’t have solar wind.
- deleted 2y ago
  [deleted]

BurningFrog 2y ago

On a tidal locked planet, conditions should be very static. The point facing the sun is the hottest, and the opposite point is the coldest. Which means there is a constant "spectrum" of climates in between, and you only need one of these thousands of microclimates to be beneficial for creating life. So this may be the planets most suitable for life, if this theory I just made up has any validity!

surgical_fire 2y ago
It does make some sense, even if life would be viable only in (for example) the twilight rim of the planet (such as around the poles)
cma 2y ago
https://en.wikipedia.org/wiki/Eyeball_planet https://en.wikipedia.org/wiki/Eyeball_planet

rybosome 2y ago

I once read an article that speculated about this. The conclusion was that perhaps there could be a ring around the planet, at the border of the side facing the sun from the side facing away from the sun. That ring could be a habitable zone.

AnotherGoodName 2y ago

A large moon should absolutely mess this tidal locking up fwiw since it will have far more influence than the star just as our moon has far more tidal influence than our sun. Not that I think tidal locking is a blocker for life but it’s also not a big deal since large moons are extremely common and therefore the tidal locking is not guaranteed.