var satrt = Cesium.Cartographic.fromDegrees(x,y,z)
var end = Cesium.Cartographic.fromDegrees(x,y,z)
var geodesic = new Cesium.EllipsoidGeodesic();
geodesic.setEndPoints(satrt, end);
var distance = geodesic.surfaceDistance return {distance,geodesic}
console.log(distance)