mars clouds

[MindToAsk]

Does anyone have a mars atmosphere {with clouds} definition? I've copied the parameters from Earth but I don't think this works in mars case.

[TERRIER]

Hello MindToAsk

Here's my complete Mars settings, taken from the solarsys.ssc file of celestia version 1.3.1pre11, while the clouds settings I added to this from the mars-clouds.zip that I originally downloaded from Bruckners site.
Maybe there are better settings for the clouds, if anyone else knows of them?

Code: Select all

"Mars" "Sol"
{
   Texture "mars.*"
   # Texture "mars8k.dds"
   BumpMap "marsbump.*"
   BumpHeight 2.5
   Color   [ 1 0.75 0.7 ]
   HazeColor [ 1 1 1 ]
   HazeDensity 0.45
   Radius 3396 # equatorial
   # Oblateness 0.0069

   Atmosphere {
      Height 30
      Lower [ 0.8 0.6 0.6 ]
      Upper [ 0.7 0.3 0.3 ]
      Sky [ 0.83 0.75 0.65 ]
                Sunset [ 0.7 0.7 0.8 ]
                # Slightly bluish sunset, as seen in true color pictures
                # from Pathfinder
   Cloudheight 10
      CloudSpeed 0
      CloudMap "mars-clouds.png"
   }

   CustomOrbit "vsop87-mars"
   EllipticalOrbit
   {
   Period            1.8809
   SemiMajorAxis     1.5237
   Eccentricity      0.0934
   Inclination       1.8506
   AscendingNode     49.479
   LongOfPericenter 336.041
        MeanLongitude    355.453
   }

   RotationPeriod        24.622962
   Obliquity             26.72
   EquatorAscendingNode    82.91
   RotationOffset       136.005

   Albedo            0.150
}

regards
TERRIER

[Guest]

I've set mine to...

CloudHeight 8
CloudSpeed 28.8

...which I believe I at one time calculated from some reference. Though at this time I can't recall my source or exact calculations. I imagine some CloudSpeed is more realistic than 0 in anycase.

[Tech Sgt. Chen]

Guest wrote:

I've set mine to...

CloudHeight 8
CloudSpeed 28.8

...which I believe I at one time calculated from some reference. Though at this time I can't recall my source or exact calculations. I imagine some CloudSpeed is more realistic than 0 in anycase.

I'm not sure if the numbers represented under cloudheight/cloudspeed are commensurate with mph, kph or some other measurement, so I hope this helps.

Cloud height: (approximate) 10 miles/16 kilometes.
Cloud Speed: (approximate) 15MPH/6.7MPS
Reference:
http://www.solarviews.com/eng/pathfind.htm

Post Script: Nice cloud pictures at that URL.

[Star Lion]

while the clouds settings I added to this from the mars-clouds.zip that I originally downloaded from Bruckners site.

His REAL site or my reconstruction of his site at http://www.bruckner.50megs.com

[Guest]

I still can't recall what site I gathered info from. But I remember how I did the calculation.

I took the aprox cloud height and speed data for earth from some site and calculated the conversion factor using Earth's clouds settings in Celestia (not that I know if those are accurate or not). I then multiplied the speed and height listed for Mars by my conversion factor.

Can anyone chime in that knows what cloudheight and cloud speed are actually measured in?

[granthutchison]

CloudHeight is in kilometres. CloudSpeed is in degrees per day (which makes sense given that the cloud texture rotates as a unit, so there is no fixed value that could be assigned for its speed in kilometres per hour).

Martian clouds seem to be at altitudes around 10-15km. Martian weather fronts pass over at 3-day intervals in temperate latitudes, so the CloudSpeed shouldn't be too far different from Earth's.

I guess it depends on what texture you're using, but one disadvantage to rotating the Martian cloud texture is that many cloud features on Mars are topographic - around the volcano summits and maybe also mist lying in the depressions. So you'll move those out of register with the underlying terrain. I tend to turn off cloud movement on the Earth, too, because I hate seeing a ghostly cloud outline of the Andes lying in the middle of the Pacific or the Atlantic.

Grant

[selden]

This obviously indicatea a situation where multiple cloud layers would be useful...

[MindToAsk]

TERRIER I'm using your settings now, thanks a lot!
Star Lion Some of the links here http://www.bruckner.50megs.com, including mars clouds, don't work.
Thanks for the link Tech Sgt. Chen

Does mars really need a specular map?

[Bob Hegwood]

Pink stratus clouds are coming from the northeast at about 15 miles per hour (6.7 meters/second) at an approximate height of ten miles (16 kilometers) above the surface. The clouds consist of water ice condensed on reddish dust particles suspended in the atmosphere. Clouds on Mars are sometimes localized and can sometimes cover entire regions, but have not yet been observed to cover the entire planet. The image was taken by the Imager for Mars Pathfinder (IMP) on Sol 16 about forty minutes before sunrise showing areas of the eastern Martian horizon. (Courtesy University of Arizona)

Got the above from the Pathfinder site... Maybe this helps?

Take care, Bob

[Bob Hegwood]

For your further edification, I'm using the following on my system with satisfactory results:

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Atmosphere {
      Height 30
      Lower [ 0.8 0.6 0.6 ]
      Upper [ 0.7 0.3 0.3 ]
      Sky [ 0.83 0.75 0.65 ]
      CloudHeight 16
      CloudSpeed 45
      CloudMap "mars-clouds.png"
   }

Hope that helps...

Take care, Bob