{
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  "kind": "invented_circular_orbit_projection_not_ephemeris",
  "inputs": {
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    "outer_radius": 1.6,
    "inner_angular_speed": 1,
    "outer_angular_speed": 0.5,
    "time_unit": "arbitrary",
    "orientation": "north view, counterclockwise; SVG y inverted"
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      "angular_rate_rad_per_time": -0.3333333333333332
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  ],
  "rate_checks": [
    {
      "t": -1.6,
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    {
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  ],
  "independent_check": "analytical angular rate cross product vs central difference dt=1e-5, tolerance1e-8",
  "limits": [
    "coplanar circular model",
    "not real Earth/Mars dates/coordinates",
    "no sky altitude/brightness or accurate loop morphology"
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}