Timeline for Can there be plants on the dark side of a tidally locked world?
Current License: CC BY-SA 4.0
7 events
| when toggle format | what | by | license | comment | |
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| Sep 4, 2019 at 9:04 | comment | added | nigel222 | Also possible (and brighter than a moon) is a binary star system, with the second star larger and brighter than the one that the planet is locked to, but distant. (It can't be close for reasons of orbital stability). | |
| Sep 3, 2019 at 14:28 | comment | added | Ilmari Karonen | @Willk: Maybe. It would have to stay shiny, though, which would probably require the surface to melt regularly. That's also hard to pull of near the life belt, although for the opposite reason. (As for Psyche specifically, Wikipedia only gives it a geometric albedo of 0.15, which is not significantly higher than the Moon's 0.12. The radar albedo of Psyche is a lot higher, but plants don't grow on radar waves.) | |
| Sep 3, 2019 at 13:48 | comment | added | Willk | @IlmariKaronen - what about a metal moon? Metal can be shiny. Like this: en.wikipedia.org/wiki/16_Psyche | |
| Sep 3, 2019 at 10:16 | comment | added | Ilmari Karonen | (A very high albedo moon would help some, since it could be smaller while still being bright. But it's hard to see how a moon around a planet warm enough for life could have such a high albedo, since most of the low molecular mass volatiles that could form a high albedo coating — like water, ammonia, etc. — would evaporate and escape so close to the sun. Unless, of course, the moon was big enough to retain them gravitationally — but then we'd basically have a double planet, and again run into the same tidal issues. Unless the planets were really far apart, but then they wouldn't stay bound...) | |
| Sep 3, 2019 at 10:09 | comment | added | Ilmari Karonen | The problem with a bright moon is that it's kind of incompatible with a tidally locked planet. Specifically, the tidal force exerted by the moon is proportional to the cube of the angular diameter, while brightness is proportional to its square. So a bright moon needs to loom big in the sky, and that means it's going to exert a strong tidal force on the planet, preventing the planet from tidally locking to anything else. | |
| Sep 2, 2019 at 16:53 | comment | added | rek | With large oceans and a thick atmosphere cycling heat, geothermal warming on the dark side isn't necessary. Current models of this sort support largely ice-free antistellar surfaces. | |
| Sep 2, 2019 at 16:49 | history | answered | Willk | CC BY-SA 4.0 |