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GroundTrack

The GroundTrack object aims at displaying the projection of the orbit of an object on the surface of a body.

Implements : CzmlPrimaryObject

Extends : AbstractPrimaryObject

Example :

{
    "id":"GROUND_TRACK/Keplerian parameters: {a: 1.0878E7; e: 0.0; i: 20.0; pa: 0.0; raan: 0.0; v: 0.0;}",
    "name":"Ground track of : Keplerian parameters: {a: 1.0878E7; e: 0.0; i: 20.0; pa: 0.0; raan: 0.0; v: 0.0;}",
    "availability":"2024-03-15T00:00:00Z/2024-03-15T10:00:00Z",
    "position":{
      "referenceFrame":"INERTIAL",
      "interpolationAlgorithm":"LAGRANGE",
      "interpolationDegree":5,
      "epoch":"2024-03-15T00:00:32.18397396802902Z",
      "cartesian":[
        0,6378137,0,0,
        59.99999642372131,6374581.709319647,200076.26656141842,72619.33859931014,
        120.00003308057785,6363919.789645215,399929.6646521222,145157.70304153176,
        180.00002950429916,6346163.093492068,599337.5771237323,217534.2033261687,
        240.00002592802048,6321331.360370292,798077.8803284918,289668.12895722286,
        300.0000223517418,6289452.1955156755,995929.1873147505,361479.03741297004]
    }
    "path":{
      "show":{
        "interval":"2024-03-15T00:00:00Z/2024-03-15T10:00:00Z",
        "boolean":true
      },
      "material":{
        "solidColor":{
          "color":{
            "rgba":[
              255,10,20,255
            ]
          }
        }
      }
    }
  }

Properties

id - String : Identification of the ground track- default : "GROUND_TRACK/{Id of the object}"

name - String : Name of the ground track, default : "Ground track of : {name of the object}".

availability - TimeInterval : Time interval when the ground track is displayed.

Intrinsinc arguments

These arguments can be used to build a ground track object :

satellite - Satellite : The satellite for the ground track.

body - BodyShape : The body which the satellite orbits.

color - Color : The color of the ground track. Default : white.

constellation - Constellation : A constellation that will take all the satellite at once to display the ground tracks.

Other parameters :

initialCartesiansSatellite - List of Cartesian : A list of the initial cartesians position of the satellite in the ITR frame.

clampedPositionOnBody - TimePosition : The position in time of the point projected on the surface of the body.

allGroundTracks - List of GroundTrack : A list that contains all ground track computed when several are needed with constellation.

Build

The ground track object can be build with :

• A Satellite, a body :

GroundTrack groundTrack = new GroundTrack(satellite, body);

• A Satellite, a body, a Color :

GroundTrack groundTrack = new GroundTrack(satellite, body, color);

• A constellation, a body :

GroundTrack groundTrack = new GroundTrack(constellation, body);

• A constellation, a body, a Color :

GroundTrack groundTrack = new GroundTrack(constellation, body, color);

Functions

displayLinkSatellite() - void : This function allows the user to display the link between the satellite and the ground track.