File:Moon rotating full 160px.gif

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Moon_rotating_full_160px.gif(160 × 160 pixels, file size: 1.56 MB, MIME type: image/gif, looped, 120 frames, 4.8 s)

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Summary[edit]

Description
English: Animated rotation of the earth's moon. The lit side of the full moon is shown, as an observer looking from the sun's direction would see it. On earth, only one side is visible, but the moon rotates relatively to the sun during one month. In order to render the animation of a full rotation, images from spacecraft beyond the moon had to be used. At the terminator near the right edge, craters can be seen most clearly.
This is a small version suitable for display in Wikipedia.
Date
Source Own work
Author Geek3
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Source Code[edit]

 
This image was created with POV-Ray.
 
This image was created with ImageMagick.

The frames of the animation were created with POV-Ray, a free 3D rendering program. Two components are required:

  • A surface color map, free image from NASA's 1994 Clementine mission.
  • An elevation map (from USGS, public domain) with grey values encoding surface altitudes. The elevation map can be used as a simple bump map for fast rendering, or (as in this case) to reconstruct a full 3D model with realistic shadows.

Executing POV-ray rendering:

povray +H160 +W160 +UA +AM1 +A0.03 +R6 +KI0 +KF1 +KC +KFI1 +KFF120 +Oframe Moon_rotating_full_160px.pov

Assembling the gif animation with ImageMagick:

convert -loop 0 -delay 4 -dispose background frame???.png -channel alpha -threshold 50% +channel +dither -colors 64 Moon_rotating_full_220px.gif

Source file Moon_rotating_full_160px.pov:

// Moon_rotating_full_160px.pov
#version 3.7;
#include "colors.inc"

global_settings { assumed_gamma 1 }

camera { location <0, 0, -220> look_at <0, 0, 0> up 0.00526 right 0.00526 }

light_source {
    <0.3,0,-1> * 200
    color White
}

// use true 3D surface
#include "functions.inc"
#declare ele=function{
    pigment{
        image_map{
            jpeg "moon_elevation.jpg" map_type 1 interpolate 2
        }
    }
}

#declare rs=0.006; // ratio of roughness to radius
isosurface {
    function { f_sphere(x,y,z, 1) + rs * (1 - ele(x,y,z).gray) }
    contained_by { sphere {0,1.01} }
    accuracy 0.00001
    max_gradient 1.2
    texture {
        pigment {
            image_map { jpeg "moon_surface.jpg" map_type 1 } }
            finish {
                ambient rgb 0.006*<1,1,1> // space is dark
                diffuse 1.4 // brightness
                brilliance 1.0 // seems most realistic
            }
        }
    scale <1,1,-1>
    rotate <0,-90+360*clock,0>
    translate <0,0,0>
}

Licensing[edit]

I, the copyright holder of this work, hereby publish it under the following licenses:
GNU head Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled GNU Free Documentation License.
w:en:Creative Commons
attribution
This file is licensed under the Creative Commons Attribution 3.0 Unported license.
You are free:
  • to share – to copy, distribute and transmit the work
  • to remix – to adapt the work
Under the following conditions:
  • attribution – You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
You may select the license of your choice.

File history

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Date/TimeThumbnailDimensionsUserComment
current00:09, 23 March 2016Thumbnail for version as of 00:09, 23 March 2016160 × 160 (1.56 MB)Geek3 (talk | contribs)== {{int:filedesc}} == {{Information |Description ={{en|1=Animated rotation of the earth's moon. The lit side of the full moon is shown, as an observer looking from the sun's direction would see it. On earth, only on...

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