Hello! I've put together my first planetary system, but as I'm not a scientist (and bad at maths) I'm reaching the limits of my brainbox and would really appreciate some fact checking! I have questions, but I'll post them in separate questions.
I know that tidally locked red dwarf planets are getting a bit overused, but quite frankly I really love the look, and as this world is going to be the backdrop of a webcomic, aesthetic is very important. Anyway, here are the specs I have so far;
Kereiol is a 2 billion year old quiescent carbon-rich M star with a temperature of 3,100 kelvins. If it flares at all they are tiny. It has four orbiting planets, only one of which, Liskuel, is within the goldilocks zone. Liskuel is 0.15 AU from Kereiol and has an orbital period of 35 days.
Liskuel is a tidally locked wet, rocky carbon-born planet with an active core. It is 1.5 times the size of earth, but with a similar mass and gravity as unlike our planet which is dominated by oxygen and silicates, it is rich in aluminium, titanium, silicon, carbon, and lithium and mostly comprised of quartz or diamond. 70% of the surface is covered in water, with especially deep oceans on the nightside.
At the substellar point high temperatures vaporise water whilst in the nightside low temperatures condense it. This condensation creates a vacuum that sucks in hot air and water from the substellar point, therefore creating a global air circulation cell. Water circulates, too – rain from the substellar point flows across the land and through the oceans to the nightside where it freezes. At the same time, frozen water is melted by the heat of the earth and flows around to the substellar side. Intense cloud formation on the nightside also minimises thermal flux, and trapped water on the nightside helps prevent the runaway greenhouse effect.
All this means that the substellar point would be baking hot with perpetual hurricanes and permanent torrential rain. The nightside would be in perpetual darkness, and a permanent ice age. The substellar hurricane would generate freak ocean waves which could be dangerous for the habitable equatorial belt where the sun never sets but hovers in a perpetual twilight. Due to rain runoff from the nearby storm, the land in the terminator belt would have large networks of river deltas and swampland. Deserts would exist, but in the rain shadows of mountains, and would be long and narrow. The crust would be largely composed of graphite and would be dark in colour. Because water absorbs red light fast and M stars don’t produce a lot of blue and purple light, photosynthesis in water may be limited to the top 10m or less. This means there are no photosynthetic reefs or deep kelps but there is a lot of floating microbial biomass.
There is a huge variety of plants. Because light only ever comes from one angle, tree foliage is perpendicular to the sun, and only grows on one side of the tree. Because Kereiol is a relatively weak source of light, the plants maximise a far wider portion of the EMR spectrum than they do on earth, meaning they present in colours we can’t see and don’t have names for. All dark colours, however, like dark red, yellow and orange, with the occasional dark purple. We see a very small fraction of the spectrum of light, which enables us to perceive the difference between night and day – but because there is no such difference on Liskuel animal species have adapted to see much more of the EMR spectrum than we can. Others have evolved without eyes.
Due to tidal locking, the only change in the amount of sunlight comes from the slight variation in distance from the sun due to the orbit being slightly elliptical. Therefore, although there is no day-night cycle in any given location, there are cycles of temperatures accompanying Kereiol’s height over the horizon. This acts as a natural clock – a morning beginning with a cold winter, followed by a pleasant spring, then a hot summer afternoon, autumn in the evening and another winter morning. This ‘day’ spans the length of Liskuel’s rotation around the sun (35 earth days.) Depending on the ‘latitude’ there may be a completely dark night in between or no night ever.
Are there any holes or issues with the system above?
P:S I've edited this to remove some questions, as I now know that those should be in separate posts. I'll put those other questions in a list below as I post them. Thanks again!