{
  "model": "uniform circular orbit viewed from above",
  "physical_scale": false,
  "angle_units": "degrees; negative SVG angles turn counterclockwise on screen",
  "marked_hemisphere": "an identity marker, not illumination",
  "cases": [
    {
      "label": "不自转",
      "positions": [
        {
          "position": 1,
          "orbital_angle": 0,
          "axial_rotation": 0,
          "moon_center_svg": [
            450.0,
            175.0
          ],
          "mark_normal_dot_earth_direction": 1.0
        },
        {
          "position": 2,
          "orbital_angle": -90,
          "axial_rotation": 0,
          "moon_center_svg": [
            350.0,
            75.0
          ],
          "mark_normal_dot_earth_direction": 0.0
        },
        {
          "position": 3,
          "orbital_angle": -180,
          "axial_rotation": 0,
          "moon_center_svg": [
            250.0,
            175.0
          ],
          "mark_normal_dot_earth_direction": -1.0
        },
        {
          "position": 4,
          "orbital_angle": -270,
          "axial_rotation": 0,
          "moon_center_svg": [
            350.0,
            275.0
          ],
          "mark_normal_dot_earth_direction": -0.0
        }
      ]
    },
    {
      "label": "同向同步自转",
      "positions": [
        {
          "position": 1,
          "orbital_angle": 0,
          "axial_rotation": 0,
          "moon_center_svg": [
            450.0,
            510.0
          ],
          "mark_normal_dot_earth_direction": 1.0
        },
        {
          "position": 2,
          "orbital_angle": -90,
          "axial_rotation": -90,
          "moon_center_svg": [
            350.0,
            410.0
          ],
          "mark_normal_dot_earth_direction": 1.0
        },
        {
          "position": 3,
          "orbital_angle": -180,
          "axial_rotation": -180,
          "moon_center_svg": [
            250.0,
            510.0
          ],
          "mark_normal_dot_earth_direction": 1.0
        },
        {
          "position": 4,
          "orbital_angle": -270,
          "axial_rotation": -270,
          "moon_center_svg": [
            350.0,
            610.0
          ],
          "mark_normal_dot_earth_direction": 1.0
        }
      ]
    }
  ]
}