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What are the hazards of a non-rotating planet?

  1. Oct 14, 2015 #1
    Ahoy - so this is a rather multi-faceted question, but I need it properly answered for a creative project of mine. I could think of no better place to ask it, so forgive me if it's misplaced.
    I have on paper before me a fictional planet that does not rotate. It's general shape is a truncated icosahedron (that of a classic soccer ball), with 32 isolated faces (12 pentagonal, 20 hexagonal, all separated by artificial mountains + potentially an invisible atmospheric barrier).
    It is orbited by an artificial sun that provides energy equivalent to that of our own, though has negateable mass, an orbital distance comparable to high-orbiting satellite, and an orbital period of 20 hours, giving us 10 hour days at the equator (the required distance to allow for this speed I have not yet bothered with). In addition to the sun is a mass-less moon (effectively a giant mirror), the orbit of which I am not certain about.
    Anyhow - moving on.
    The planet is artificial, and hence lacks the organic layers integral to the maintenance of a magnetic field. The system is entirely isolated - that is to say, assume for the question's sake that there is nothing beyond the orbit of the sun, and hence no extra-system cosmic bombardment.
    Here are the planet's values:
    M = 3.07e24 kg
    Radius = 5.021e6 m
    Surface Gravity = 8.122388658 m/s^2

    The artificial sun has a perfectly circular orbit about the equator of the planet.
    Each of the 32 regions has an independent atmospheric composition (how, I don't know yet), and you should assume that any winds in a region's air would be specific to the region's unique atmosphere and temperature (and thus pressure).
    The surface is also artificial, and so does not flow. There is no tectonic activity.

    What sort of issues would arise with a non rotating planet that artificially maintained a stable atmosphere, that presumably lacked a magnetic field, and that was the center of it's own small solar system?

    Thanks, and sorry.
  2. jcsd
  3. Oct 15, 2015 #2
    I guess it could be depressing if you don't like football.

    Weather would be rather dull and there would be no tides.

    I wouldn't expect much diversity in any long term life. No cosmic rays reduce the number of genetic changes over time. Overall, the prospect for advanced life to form from scratch is statistically very low without the normal planetary and cosmic dynamics.
  4. Oct 15, 2015 #3
    Thankyou for your answer - I hadn't thought to consider the effect of cosmic radiation on evolution.
    Can somebody elaborate on what they might imagine the weather systems would be like? Lacking a coriolis effect, (but remembering that this situation is not analogous to a stationary earth with the same relationship to our sun, but instead is orbited by an artificial sun) the planet still has a 20 hour day/night cycle, and there are many mountains arranged in pentagonal and hexagonal enclosures like a soccer ball (regions the size of countries). I need to figure out what different regions would experience weather-wise. Would strong winds and weather patterns be plausible at all?
  5. Oct 16, 2015 #4
    What is it? A prison planet for football hooligans? ;)

    If those 32 regions have separate atmospheric composition, then, I'd assume that they should be somehow isolated, thus no winds between them.

    The light would lit polls at even higher angle, so they would receive less light than when orbiting a star. Heat transfer to the pools may be tricky. If no tilt and no air circulation, they may be really cold with at least frozen CO2.

    Air in each such cell would expand a bit during day and contract back during night. Nothing special. What for sure would remain would be winds between sea and land, based on day-night cycle.

    Volcanoes have great role in providing land with nutrients, without them the soil can become really low quality.

    I do not see here any special impediments for intelligent life. You don't need cosmic ray for mutations, you still have some background radiation and imperfect copying.
  6. Feb 29, 2016 #5
    The planet would lose the water from the middle and the world would be like death. Just like if the moon was not there
  7. Feb 29, 2016 #6
    The winds would blow from the polar direction toward the equator (presumably in each cell). Lacking oceans, they would be the only significant form of heat transfer. They would blow hard. (This could be offset if you wished by providing some other heat transfer mechanism, underground rivers or whatnot.)

    Most mutations have nothing to do with radiation. They are caused by miscopied DNA. A typical human for example has about 3 mutations (usually in junk DNA). The rates of such miscopies depend on how good the cells are at detecting and correcting miscopies, plus how many germ-line copies are needed per generation. A species with too tight control on their DNA never evolves, one with too loose control has too many nonviable offspring.
  8. Mar 1, 2016 #7


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    So the planet does not rotate but the artificial star does rotate around it? If that is the case then there would be no side effects that a non rotating planet normally would suffer. However you said that the artificial star's output is equivalent to our own but it orbits only a few thousand miles away from the planet, that would render the planet uninhabitable. You either need to keep the star at 1AU or lower the star's output appropriately. If you want it 20K miles away then the star would only need to be a fraction as luminous as our own star, that is the inverse square law in effect.
  9. Mar 1, 2016 #8
    Not true. You loose the Coriolis effects of a non-rotating planet, which will have a significant effect on weather, at the least.
  10. Mar 1, 2016 #9


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    True. Normally I would consider that a problem but the OP has already decided that the environment is going to be highly customized in that there will be dozens of local spheres of weather.
    Last edited: Mar 1, 2016
  11. Mar 1, 2016 #10
    I may be completely wrong, but I have always thought that everything in the Universe rotates. Wouldn't a non-rotating planet be impossible?
  12. Mar 1, 2016 #11


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    A rotating planet can be turned into a non-rotating planet simply by attaching powerful enough rockets at antipodal points on its equator and using them to slow down the rotation until it stops.
    Such planetary engineering is well beyond we homo sapiens, but the Magratheans could probably manage it.
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