Русский New site

Advanced search

[ New messages · Forum rules · Members ]
Page 1 of 11
Forum » SpaceEngine » General Discussions » The multi-planet system around Gliese 667 C, 3 in the HZ (Suggestions for modelling some nearby real exoplanets)
The multi-planet system around Gliese 667 C, 3 in the HZ
dissemblyDate: Friday, 15.11.2013, 18:01 | Message # 1
Observer
Group: Users
Australia
Messages: 13
Status: Offline
Hi all,

I just downloaded this beautiful program last night and have been playing with it until 4am. I've been using the Gliese 667 C system (which is a real planetary system - Exoplanet.EU catalogue entries for GJ 667 C), because it has three planets potentially in the habitable zone and I've been thinking about what they might look like.

So I wrote the below to try and model them. I thought I'd post it up because I did something different to what the program normally does with close-in planets in the HZ of a red dwarf (i.e. it has one half of the planet iced over, and the other half shows a massive gyre at the sub-solar point). I don't have any problem with this model but I wanted to model another possibility - a super-rotating atmosphere that evenly warms the whole planet. So I made the rotation periods one day shoter than the year of the two planets GJ 667 C e & f, to prevent the iced-over model from appearing, and I gave them very fast, very high cloud decks.

The closer HZ planet ("f") I decided to make quite hot, with a high atmospheric pressure and no oceans (its oceans are up in the cloud deck and trapped in the biosphere - maybe this protects it; there was that paper recently that suggested cloud cover greater than 50% could shift a habitable zone inward quite substantially), and dark-green foliage (it has a relatively close position to the star, and so would get a lot of white light despite the redder overall spectrum). Trying to picture a steamy world that's not so far gone that it's about to tip over into a Venus-like state (but maybe in a few million years?).

The one thats further away ("e") gets less light, so I gave it black-leaved vegetation to soak up every little bit it can. I also gave it a lower atmospheric pressure and fewer clouds, but of course kept a high cloud deck and a super-rotation (to warm the nightside). This is a cooler world with a lower air pressue and deep, unevaporated oceans. I imagine it would be more pleasant to visit, even though it would look more alien with its darker, more red-dwarfy vegetation.

Neither has polar caps; ice absorbs longwave radiation better, and red dwarf stars give off more of that - there was a paper recently that suggested that snowball states are less likely around cooler stars for this reason. So I didn't allow any difference between tropics and poles. (This isn't why I didn't let them be tidally-locked, btw; of course this effect wouldn't hold for ice caps stuck permanently in the dark; I just suggest very vigorous atmospheric heat transfer to eliinate that.)

To experiment with the code I also played around with the next planet out, a super-earth, by trying to give it some evidence of a recent cataclysm (a ring-system and a series of asteroid moons). I tried to make it cratered, but I can't seem to get the hang of increasing the cratering properly... i don't have a sense of what the numbers really mean yet. sad

Anyway, because these are real planets (only their details are imaginary), and weren't automatically included with the version I downloaded, I thought I'd post it up for others to see.

I put the below code straight into the pre-existing ExoPlanets.sc file - please note that the "b" and "c" planets come bundled with SpaceEngine, so be careful not to double up on them.

Code
Planet    "Gliese 667 C b"
{
   ParentBody     "Gliese 667 C"
   Mass            5.6  //5.466676
   Orbit
   {
    Epoch          2454443.1
    Period         0.01971020928
    SemiMajorAxis  0.0504
    Eccentricity   0.13  //0.09
    ArgOfPericen  -4
   }
}

Planet    "Gliese 667 C c"
{
   ParentBody     "Gliese 667 C"
   Mass            3.8 //4.26388
   Orbit
   {
    Epoch          2454462
    Period         0.07701738951
    SemiMajorAxis  0.1251
    Eccentricity   0.020 //0.34
    ArgOfPericen   166
   }
}

Planet    "Gliese 667 C f" //added by David 15-11-2013
{
   ParentBody     "Gliese 667 C"
   Class           "Terra"     // Class of a planet   
   Mass            2.7
   Orbit
   {
    Epoch          2454462
    Period         0.1068473648186174
    RotationPeriod  912.6240000000001 // Rotation period in hours set to prevent tidal locking effects   
    SemiMajorAxis  0.156
    Eccentricity   0.03
    ArgOfPericen   103
   }

   Surface         // Surface tag
       {

           BumpHeight      6.0     // Max height of landscape in km

           Life            true    // true, if there is life on the planet

     climatePole     0.7       // Climate of poles   - index to color table (0...1)
     climateTropic   0.7       // Climate of tropics - index to color table (0...1)
     climateEquator  0.7       // Climate of equator - index to color table (0...1)   

     mareFreq        0.0387382   // Lunar mare frequency
     mareDensity     0.06008458  // Lunar mare density
     montesMagn      0.6009584   // Mountains magnitude (0...1)
     montesFreq      50.9121    // Mountains frequency
     montesDensity   0.108095    // Mountains density
     dunesMagn       0.04444444  // Dunes magnitude (0...1)
     dunesFreq       0.8876     // Dunes frequency
     dunesDensity    0.5669919   // Dunes density
     hillsMagn       0.1289276   // Hills magnitude (0...1)
     hillsFreq       50.3618    // Hills frequency
     hillsDensity    0.2554457   // Hills density
     canyonMagn      0.6341905   // Canyons magnitude (0...1)
     canyonFreq      263.7023    // Canyons frequency
     canyonDensity   0.4370083   // Canyons density
     cracksMagn      0.0  // Ice cracks magnitude (0...1)
     cracksFreq      0.0   // Ice cracks frequency
     cracksOctaves   0           // Number of ice cracks octaves
     craterMagn      0.9358109   // Craters magnitude
     craterFreq      0.0  // Craters frequency
     craterDensity   0.0  // Craters density
     craterOctaves   4.606928    // Number of craters octaves
     craterRayedFactor 0           // Number of rayed craters relative to usual craters   

     colorSea       (0.040, 0.100, 0.200, 1.000) // Color of seas
     colorShelf     (0.150, 0.480, 0.460, 1.000) // Color of shelf areas
     colorBeach     (0.940, 0.970, 0.737, 0.000) // Color of beach lines - milky-yellow sand

     colorLowPlants (0.000, 0.000, 0.000, 0.000) // Color of lower vegetation - black
     colorUpPlants  (0.058, 0.145, 0.000, 0.000) // upper vegetation - dark green
    }

      Clouds      // This is the upper Venus-like superotation
       {

           Height          65.0     // Height of cloud layer in km
           Velocity        150000.0    // Velosity of clouds layer
           Color          (1.0, 1.0, 1.0)  // Global color of clouds layer

           Coverage        0.3     // Clouds coverage (0...1)
           twistZones      1    // Number of Jupiter-like zones or strips
           twistMagn       3.5    // Strength of twist
    }   

    Ocean
    {
     Height          1.5
    }   

    Atmosphere      // Atmosphere tag
       {
           Height          100    // Height of the top boundary in km
           Pressure        2.1     // Surface pressure in bars
           Greenhouse      40.0    // Greenhouse effect in degrees
       }   

}

Planet    "Gliese 667 C e" //added by David 15-11-2013
{
   ParentBody     "Gliese 667 C"
   Mass            2.7
   Orbit
   {
    Epoch          2454462
    Period         0.170403832991102
    RotationPeriod  1476 // Rotation period in hours set to prevent tidal locking effects
    SemiMajorAxis  0.213
    Eccentricity   0.02
    ArgOfPericen   29
   }

   Surface         // Surface tag
       {

           BumpHeight      10.0     // Max height of landscape in km

           Life            true    // true, if there is life on the planet

     climatePole     0.7       // Climate of poles   - index to color table (0...1)
     climateTropic   0.7       // Climate of tropics - index to color table (0...1)
     climateEquator  0.7       // Climate of equator - index to color table (0...1)   

     mareFreq        0.0387382   // Lunar mare frequency
     mareDensity     0.06008458  // Lunar mare density
     montesMagn      0.6009584   // Mountains magnitude (0...1)
     montesFreq      40.9121    // Mountains frequency
     montesDensity   0.108095    // Mountains density
     dunesMagn       0.04444444  // Dunes magnitude (0...1)
     dunesFreq       0.8876     // Dunes frequency
     dunesDensity    0.5669919   // Dunes density
     hillsMagn       0.1289276   // Hills magnitude (0...1)
     hillsFreq       50.3618    // Hills frequency
     hillsDensity    0.2554457   // Hills density
     canyonMagn      0.6341905   // Canyons magnitude (0...1)
     canyonFreq      263.7023    // Canyons frequency
     canyonDensity   0.4370083   // Canyons density
     cracksMagn      0.0  // Ice cracks magnitude (0...1)
     cracksFreq      0.0   // Ice cracks frequency
     cracksOctaves   0           // Number of ice cracks octaves
     craterMagn      0.9358109   // Craters magnitude
     craterFreq      0.0  // Craters frequency
     craterDensity   0.0  // Craters density
     craterOctaves   4.606928    // Number of craters octaves
     craterRayedFactor 0           // Number of rayed craters relative to usual craters
     cycloneFreq     1.7607107   // Cyclones frequency    

     colorSea       (0.040, 0.100, 0.200, 1.000) // Color of seas
     colorShelf     (0.150, 0.480, 0.460, 1.000) // Color of shelf areas
     colorBeach     (0.940, 0.970, 0.737, 0.000) // Color of beach lines - milky-yellow sand

     colorLowPlants (0.000, 0.000, 0.000, 0.000) // Color of lower vegetation - black
     colorUpPlants  (0.000, 0.000, 0.000, 0.000) // was 0.058, 0.145, 0.000, 0.000 - dark green
    }

      Clouds      // This is the upper Venus-like superotation
       {

           Height          50.0     // Height of cloud layer in km
           Velocity        140000.0    // Velosity of clouds layer
           Color          (1.0, 1.0, 1.0)  // Global color of clouds layer

           Coverage        0.2     // Clouds coverage (0...1)
           twistZones      10    // Number of Jupiter-like zones or strips
           twistMagn       0.0    // Strength of twist
    }   

    Ocean
    {
     Height          7.0
    }   

    Atmosphere      // Atmosphere tag
       {
           Height          90    // Height of the top boundary in km
           Pressure        0.95     // Surface pressure in bars
           Greenhouse      30.0    // Greenhouse effect in degrees
       }   

}

Planet    "Gliese 667 C d" //added by David 15-11-2013
{
   ParentBody     "Gliese 667 C"
   Mass            5.1
   Orbit
   {
    Epoch          2454462
    Period         0.2507871321013005
    SemiMajorAxis  0.28
    Eccentricity   0.03
    ArgOfPericen   7
   }

Surface         // Surface tag
       {

     craterMagn      2.9358109   // Craters magnitude
     craterFreq      184.14884    // Craters frequency
     craterDensity   100.05892152  // Craters density

    }   

      Atmosphere      // Atmosphere tag
       {
           Model          "Mars"  // Model of the atmosphere
           Height          90.0    // Height of the top boundary in km
           Pressure        0.3     // Surface pressure in bars
           Greenhouse      0.0    // Greenhouse effect in degrees
       }   

       Rings       // Ring and moon system around C d is intended to simulate recent collision that showered the planet with debris
       {
           // Texture parameter is commented out, becuase
           // this planet use procrdural generation of texture
           //Texture         "Icarus-rings.*"  // Rings texture
           InnerRadius      23018.5  // Inner raduis of rings system in km
           OuterRadius      87438.3 // Outer radius of rings system in km
           RotationPeriod   43.3    // Rings rotation period in hours
           RotationOffset   60.0    // Rings rotation phase in degrees
           FrontBright      1.0     // Direct lighting brightness
           BackBright       5.0     // Back lighting brightness (scattering)
           Density          3.0     // Density (opacity)
           Exposure         2.0     // Global brightness
       }   

}

DwarfMoon    "Gliese 667 C d 1" //totally fictional
{
   ParentBody     "Gliese 667 C d"
   Class          "Asteroid"

   Orbit
   {
    SemiMajorAxis  1.5333333333333333333333333333333e-4
    Eccentricity   0.0
    Inclination    0.0
   }
}

DwarfMoon    "Gliese 667 C d 2" //totally fictional
{
   ParentBody     "Gliese 667 C d"
   Class          "Asteroid"

   Orbit
   {
    SemiMajorAxis  5.8666666666666666666666666666667e-4
    Eccentricity   0.0
    Inclination    0.0
   }
}

DwarfMoon    "Gliese 667 C d 3" //totally fictional
{
   ParentBody     "Gliese 667 C d"
   Class          "Asteroid"

   Orbit
   {
    SemiMajorAxis  0.0006
    Eccentricity   0.0
    Inclination    0.0
   }
}

DwarfMoon    "Gliese 667 C d 4" //totally fictional
{
   ParentBody     "Gliese 667 C d"
   Class          "Asteroid"

   Orbit
   {
    SemiMajorAxis  6.1333333333333333333333333333333e-4
    Eccentricity   0.0
    Inclination    0.0
   }
}

DwarfMoon    "Gliese 667 C d 5" //totally fictional
{
   ParentBody     "Gliese 667 C d"
   Class          "Asteroid"

   Orbit
   {
    SemiMajorAxis  6.2666666666666666666666666666667e-4
    Eccentricity   0.0
    Inclination    0.0
   }
}

Planet    "Gliese 667 C g" //added by David 15-11-2013
{
   ParentBody     "Gliese 667 C"
   Mass            5
   Orbit
   {
    Epoch          2454462
    Period         0.7014373716632444
    SemiMajorAxis  0.55
    Eccentricity   0.08
    ArgOfPericen   52
   }
}


Edited by dissembly - Friday, 15.11.2013, 18:08
 
Forum » SpaceEngine » General Discussions » The multi-planet system around Gliese 667 C, 3 in the HZ (Suggestions for modelling some nearby real exoplanets)
Page 1 of 11
Search: