Kepler Orbital Elements

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    text { font:12px Inter, sans-serif; fill:#0f172a; }
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  <text x="170" y="200">Focus (body)</text>
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  <text x="60" y="200">perihelion</text>
  <text x="350" y="200">aphelion</text>
  <text x="220" y="60">a — semi-major axis</text>
  <text x="220" y="200">e — eccentricity</text>
  <text x="50" y="30" class="lab">i — inclination</text>
  <text x="50" y="50">Ω — longitude of ascending node</text>
  <text x="50" y="70">ω — argument of perihelion</text>
  <text x="50" y="90">ν — true anomaly (at epoch)</text>
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  <text x="330" y="135" class="lab">satellite</text>
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