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Planet w/ various atmospheres/colors/suns?

  1. Jun 3, 2015 #1
    Ok, hear me out, I have a terrestrial planet that has mostly a thick atmosphere. The clouds absorb most of the sunlight, therefore barely anything gets through (similar to Venus). There are, however, certain "spots" or "safe zones", so to say, that are habitable for people to live in. There are three total, and each is different from one another. The southernmost is a cold desert similar to Mars, the middle safezone is most like a jungle, and the northernmost area has snow, ice and some tundra. Simple concept so far.

    Another thing I wanted to apply, was the color of the sky and the sun. Each safe zone has skies of various colors, rather than one consistent. The northernmost has a yellow/white sun with a violet sky, the middle a violet/blue sun with yellow/orange skies, and the south a red sun with green skies (dust kicking up to alter the sky color).

    Now, I looked up the color of stars and their temperatures, and how they would apply to our eyes. I know violet and green stars cannot be seen because of how we see color, but I was wondering if there could be some sort of organic/natural filter in the atmosphere that changes the color to those inhabiting the planet? Dust, vug, algae? I know in space the sun appears white, while here on earth its a orange/yellow hue.

    Lastly, I'm wondering if these stars should be in a trinary star system, or if it could be three small neutron stars rotating around one planet? Or maybe it's just one star and the chemicals somehow affect the sky/sun color? My concern is that the neutron stars and their strong gravitational fields would tear the planet apart, and that the trinary star system seems overly complex. Though I'm willing to figure it out, it'd be difficult for various locations on the planet to have a sun particular to that region. I don't think it's possible. Probably going to go with one star with the atmosphere having various impurities altering its color. I just don't know if its feasible in a realistic sense.

    Any advice would be great. Perhaps I'm overthinking it, but I've been overthinking it for months now. I need help on what to do, with sound scientific research and a bit of elbow room for creativity. I already have a solid idea/theory on what I want it to be, but before I proceed, I'd like some advice. Thanks!
    Last edited: Jun 3, 2015
  2. jcsd
  3. Jun 3, 2015 #2
    The color of the star and sky as seen by an observer on the planet can be changed by the elements or compounds present in the location. Your planet need three separate bands of atmosphere (similar to Jupiter bands), however these bands should stay separate from one another.
    I think this is realistic because the color of the Earth's sky also changes during sunsets.

    I am more concerned on your habitable zones. The cold desert part needs certain gases that do not trap heat, so if you want to have a thick atmosphere, be sure that the atmosphere at this part is not similar to greenhouse gases, you can also use this concept on the third part. As for the second one, the jungle, since the light from the star barely touches the surface of the planet, be sure that your ecology is non-photosynthetic, you also need to know on how the whole ecosystem works for this area.

    These are my opinions. I'm not really an expert when it comes to planetary atmospheres.
  4. Jun 4, 2015 #3
    The only idea that I have - you have thick atmosphere, warm planet and only habitable zones are mountain ranges / plateaus where the pressure and temperature are OK for humans.

    Unworkable. You may play a bit with star color / atmospheric composition, but it it would apply to whole planet.

    Volcanic activity? Aurora borealis?

    If you bring in to the system a neutron star you bring up some hard to apply issues:
    -gravity (this is the smallest)
    -if you have a neutron star it means not so long ago you had here a supernova (which evaporated nearby planets, and there would not enough time for forming new planets...)
    -gamma radiation

    For me it seems that you are doing it in the wrong way.
    You start up with weird phenomena that you want to, and look hard to create exactly what you ask for.
    Maybe you should look up some natural phenomena that produce weird results?
    Last edited: Jun 4, 2015
  5. Jun 4, 2015 #4
    The safe zones do not have thick atmospheres. It's sort of like a hole in the ozone, except with the thick atmosphere/clouds being pierced. I honestly don't have a scientific reasoning for this, I just needed a reason for a really diverse planet without doing something so incredibly fantastical ie time travel, interdimensional tearing, etc.. These places need to be physically connected to one another. I suppose that's where the whole 'fiction' part comes in.

    The safezone areas allow sunlight to come through, thus life (that had existed prior to the apocalyptic event that caused these conditions) can continue existing. Not that it's a paradise by any means, but its something. I really like the idea of different bands. As for the ecosystem, I could have the plants/trees be a darker, black hue. I already have it written that the plants have more of a dark bluish hue, but it isn't anything set in stone. I'm also going to look into non-photosynthetic plant ideations.
  6. Jun 4, 2015 #5
    I'm more than likely going to go with a red dwarf system. The various safe zones, where the atmosphere is not nearly as thick, all hold conditions that will filter the atmosphere thus the color of the sun. The south will have dust kick up and alter the sky and sun color, the middle jungle will have plants that release gases into the atmosphere, and the northern more than likely will have a normal sky color. Now one thing I read online, is that to humans, a red dwarf would produce a green or yellow sky color.. I'm not sure how true that is, would you have any idea? I figured the sky would be a deep red naturally, but of course, the atmospheric conditions do change that.

    Keep in mind, these areas are geographically far apart, and aren't connected in any way. I wanted a planet with diverse conditions similar to earth but not quite as "alive". I really don't want to fall into the single-biome planet trope.
  7. Jun 4, 2015 #6
    To keep these atmospheres to stay in place (that is, to avoid the wind to carry the atmospheric particles from mixing each other), your atmospheric pressure must be equal to each location (this is where complicated parts might come out, you need to know the meteorological effects of each terrain).
  8. Jun 5, 2015 #7
    No. A neutron star is far more massive than a planet.
    Not unless the orbital period is under ten or so hours.

    It is easy to have a planet tidally locked to one sun. Then that sun is only ever seen on the near side. Though the other suns probably rise and set there.
    Nonsense. The first exoplanets specifically orbit a neutron star. Not coincidentally, a pulsar (because an old neutron star which is not a pulsar is invisible for us).

    Would an old neutron star in a distant binary with a quiet main sequence star be a pulsar?
  9. Jun 5, 2015 #8
    But he wants planets with life and for that he needs more than bilion year, in the mean time the pulsar would fade away and be undetectable.

    Mountains / plateaus ;)

    "Yellow/green" - sounds quite plausible to me.
    Complicated answer: black body radiation + Rayleigh scattering
    Simple answer: Sun seen from space is actually white, while the atmosphere scatters the light - short waves go scattered - so you get blue sky, while the rest what stays makes it look yellow

    Easy part ;)

    For red dwarf planet you have tidal lock.
    In consequence you have:
    -big stormy area with clouds, where star is almost exactly in the highest place on the sky
    -desert zone
    -some moderate climate zone
    -the dark part of planet (permanent darkness, cold)
  10. Jun 5, 2015 #9
    Yes, for us.

    What would an old neutron star look like for an observer at a distance of 3 million km?
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