What is altitudeMode/gx:AltitudeMode in reference to for Google Moon?
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I am writing a script for Google Moon that is creating a 'fly by' of the moon using trajectory data that contains latitude, longitude, and altitude. The altitude is in reference to the absolute center of the moon. In order to create a smooth flyby (using gx:FlyTo), I need to set altitudeMode to "absolute". However, according to the [reference page][1], "absolute" is in reference to sea level. The moon obviously doesn't have a sea, so what is "absolute" in reference to in the context of Google Moon?


  [1]: https://developers.google.com/kml/documentation/kmlreference#camera