Welcome Guest [Log In] [Register]
Add Reply
Cave planet
Topic Started: Jan 29 2014, 11:35 AM (101 Views)
Zireael

A/N: Restarting my project from the SpecEvo boards, hoping for more feedback.

This was originally for a fantasy story/RPG that I abandoned due to lack of time. And I know nothing about science.

***

The structure of the planet (kudos to Holbenilord from SpecEvo)
Posted Image

Posted Image

Environmental conditions
- Surface non-inhabitable, rocky. The planet has a high eccentricity (0.2) and therefore the conditions on the surface vary wildly.
- The crust separating the inhabitable zone from the surface is thick enough that no being has ever dug through it, no technology on the planet would allow it.
- The internal structure of the planet is similar to Jupiter's moon Europa, but with a thinner mantle, a bigger inhabitable zone and a thicker crust. (see diagrams above)
- The caverns are vast (miles in every direction)
- Temperature range under the surface: from -15 degrees Celsius (furthest from the core) to 50 degrees Celsius (still habitable space the closest to the core). Various biomes in the caverns - from subsurface lakes/oceans to desert-like caverns and underground jungles.
- Week length - 8 days. Year length - 416 days (assuming 52 weeks per year) => 1.09 AU orbit with a G-type star, the planet is at 0.8 AU in periphelium and 1.308 AU in apophelium. It practically fits in the habitable zone (0.82 AU to 1.2 AU).
- Rotation period 20-24h.
- Density ~3 g/cm3. Diameter 7250 km (0,56*Earth's) gives us 0.31 G (Earth gravity) on the surface.
- Water exists in liquid state below the surface.


Life on the planet
- Animal and plant life exists. There is no dirt as such, plants derive their sustenance from rocks themselves.
- Photosynthetic/chemosynthetic organisms exist, giving the max luminescence in the cavernscape around civil-twilight level, ~3-4 lux - and a possible "starry sky" effect. After all, we humans experience such conditions for longer periods of time in areas affected by midnight sun/polar night.
- Possible modes of vision used: di- or trichromatic life? Or would they be monochromatic all, since color wouldn't be necessary? Or maybe they'd be tetrachromatic in order to be able to pick up IR?

Intelligent humanoid life
- Intelligent humanoid life exists. Technology level roughly equivalent to Middle Ages (with some minor exceptions).
Offline Profile Quote Post Goto Top
 
Zireael

Questions:
- how does gravity increase when getting closer to the planet's core?
- can we have changeable gravity reference point in a plausible way?
- how does axial tilt influence seasons? would we have seasons with a tilt of 90 or 1? The only thing I found is this link
Offline Profile Quote Post Goto Top
 
martiitram
Member Avatar
Very Active Member
[ *  *  * ]
Cool!
Offline Profile Quote Post Goto Top
 
Olympianmaster
Member Avatar
Very Active Member
[ *  *  * ]
I'm not sure, but I think our tilt is 90, and how bigger the tilt, the more influenced the seasons.
Offline Profile Quote Post Goto Top
 
1 user reading this topic (1 Guest and 0 Anonymous)
« Previous Topic · Extraterrestrial Evolution · Next Topic »
Add Reply

Black Water created by tiptopolive of the Zetaboards Theme Zone