habitable planets orbiting M dwarfs
- Thread starter mike wightman
- Start date
RainOfSteel
SOC-14 1K
Let's see what Mal's view on it is.
Liam Devlin
SOC-14 5K
kewlness! ty Sigg!
M
Malenfant
Guest
This is old news to me, since I was following some of that mid-90s research that was mentioned in the article
. But yeah, it certainly sounds reasonable (and I've been assuming that to be the case for a while anyway)
Liam Devlin
SOC-14 5K
I certainly allow for such when "fleshing out" a UWP system with a far companion dwarf in them! They tend to be colder worlds, even if I roll up a breathable atmosphere.
Of course, the "habitable zone" rules for such in the TNE-handbook place that at zero working with conventional wisdom prior to tis article they'd have to be in orbit 0 due to amount of heat/ light etc they exert...
Of course, the "habitable zone" rules for such in the TNE-handbook place that at zero working with conventional wisdom prior to tis article they'd have to be in orbit 0 due to amount of heat/ light etc they exert...
Liam Devlin
SOC-14 5K
Aye, and rapid growing/ shortlived life forms! Ahh the possibilities! 
mike wightman
SOC-14 10K
If its tidally locked to the star wouldn't that put one side in permanent light and the other in darkness?
Think of the different ecosystems that would develop on the two sides of the planet, and the fun to be had in the boundary zone...
Think of the different ecosystems that would develop on the two sides of the planet, and the fun to be had in the boundary zone...
Fritz_Brown
Super Moderator
I think the boundary zone would be the only place you could count on much of an ecosystem. It would extend into the other sections, with some funky results, but huge portions of the light and dark parts would be barren dessert or frozen waste.
What about the transfer of hot air to the cool side? Especially if the planet was at a distance so that it received less energy per square foot then we do. The bright side could be quite moderate and the dark side would be quite frozen.
Would it have to be close enough to be tidally locked? How close are ewe talking about?
Would it have to be close enough to be tidally locked? How close are ewe talking about?
Fritz_Brown
Super Moderator
I'm betting it would have to be tidally locked (thought I actually saw that mentioned somewhere...). And, if it doesn't rotate, how would the air move from hemisphere to hemisphere? I know there would be some "trade winds", but I don't think it would really move much air to the cold side - that only works well when you're talking vertical mixing.
mike wightman
SOC-14 10K
A tidally locked world still spins on its axis, only it does so at the same rate as it orbits its star.
You would also still have convection currents in the atmosphere moving the gas around.
You would also still have convection currents in the atmosphere moving the gas around.
Isn't the effect of the spin reduced because it is taking weeks instead of 24 hours?
I had figured that the air would mix, heat would bleed into the dark region and then be lost as radiation to space.
" You would also still have convection currents in the atmosphere moving the gas around."
This is just a guess:
The far point from the star would be a frozen cap but as you approached the terminator the temperature would rise and be rather constant as the planet is tidally locked.
Climate regions would be drawn as concentric circles starting at the very hot "east pole" on the hot side and ending at the very frozen "west pole" on the other side. No sunset, no sunrise, no change in seasons. Boy find the right region and you could produce food like nuts growing it 24/7.
I had figured that the air would mix, heat would bleed into the dark region and then be lost as radiation to space.
" You would also still have convection currents in the atmosphere moving the gas around."
This is just a guess:
The far point from the star would be a frozen cap but as you approached the terminator the temperature would rise and be rather constant as the planet is tidally locked.
Climate regions would be drawn as concentric circles starting at the very hot "east pole" on the hot side and ending at the very frozen "west pole" on the other side. No sunset, no sunrise, no change in seasons. Boy find the right region and you could produce food like nuts growing it 24/7.
Fritz_Brown
Super Moderator
Yep, your "poles" would be toward and away from the sun.
Your plants would be OK, if they didn't get baked. Constant light on many plants makes them grow poorly.
I said the air wouldn't mix well just due to the "tradewinds". I would think you would get heat transfer, but your air would tend to be more stagnant than on a rapidly spinning world like Earth. I would also think the coriolis (which arises from the Earth's rotation) would be overwhelmed by the gravity well that is tidally locking the planet. Your atmosphere (and probably your planet) would be very egg-shaped, I would think, alos.
Your plants would be OK, if they didn't get baked. Constant light on many plants makes them grow poorly.
I said the air wouldn't mix well just due to the "tradewinds". I would think you would get heat transfer, but your air would tend to be more stagnant than on a rapidly spinning world like Earth. I would also think the coriolis (which arises from the Earth's rotation) would be overwhelmed by the gravity well that is tidally locking the planet. Your atmosphere (and probably your planet) would be very egg-shaped, I would think, alos.
Liam Devlin
SOC-14 5K
We of course are basing life as we know it ideas here on such matters gentlemen. plantlife is extremely adaptable to its environment. The ecosphere might not be very rich at all, and down to just a few hardy types of organisms that can endure the colder dark side rotation until it once again feel the heat of the sun/dwarf star (such as it is).
Planets within the habitable zone of 0 by the *rules* of system creation we have in traveller, tend to be a maximum of Size 3, although this week we've had news of a planetary body with a moon out beyond Pluto, so in RW-RL Mother Nature [or the "Ancients" in a game setting] could surprise us all still.
Fritz88: You thinking of the type *F* elliptical atmosphere aren't you?
Planets within the habitable zone of 0 by the *rules* of system creation we have in traveller, tend to be a maximum of Size 3, although this week we've had news of a planetary body with a moon out beyond Pluto, so in RW-RL Mother Nature [or the "Ancients" in a game setting] could surprise us all still.
Fritz88: You thinking of the type *F* elliptical atmosphere aren't you?
Fritz_Brown
Super Moderator
Liam, if its tidally locked, the other side will NEVER see the sun. So everything would have to live in that transition area.
Don't know what a type *F* is, but I guess so.
And, you are right on about "what we know".
Don't know what a type *F* is, but I guess so.
And, you are right on about "what we know".
Liam Devlin
SOC-14 5K
ERROR! Sorry Fritz88!
D-exotic-(Dense/very high)atmosphere <breathable at higher elvations only>
E type atmosphere is Exotic: elliptical/ egg shaped.
F-is exotic (thin/ low)--as in low areas, deep canyons.
=================================================
Tidally locked, as in it doesn't rotate at all? Hmmm. then we're looking [agreed] at the planet's *borderlands*..the shadowed twilight between darkness and baked apple radiation desert hot for life as we know it on Terra...life as we might find it...another story!
D-exotic-(Dense/very high)atmosphere <breathable at higher elvations only>
E type atmosphere is Exotic: elliptical/ egg shaped.
F-is exotic (thin/ low)--as in low areas, deep canyons.
=================================================
Tidally locked, as in it doesn't rotate at all? Hmmm. then we're looking [agreed] at the planet's *borderlands*..the shadowed twilight between darkness and baked apple radiation desert hot for life as we know it on Terra...life as we might find it...another story!
