CZMLGroundStation.md

+This page describes the content of a CZML document. Please read [How to get started]() for an explanation of how a CZML document is put together.
+
+**Extends** : [CZMLPrimaryObject](CZMLPrimaryObject)
+
+**Example** :
+```json
+{
+    "id":"Toulouse Frame",
+    "name":"Toulouse Frame",
+    "availability":"2022-01-17T12:00:00Z/2022-01-17T13:00:00Z",
+    "billboard":{
+      "horizontalOrigin":"CENTER",
+      "color":{
+        "rgba":[
+          0,255,255,195
+        ]
+      },
+      "image":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAYAAAAf8/9hAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsMAAA7DAcdvqGQAAACvSURBVDhPrZDRDcMgDAU9GqN0lIzijw6SUbJJygUeNQgSqepJTyHG91LVVpwDdfxM3T9TSl1EXZvDwii471fivK73cBFFQNTT/d2KoGpfGOpSIkhUpgUMxq9DFEsWv4IXhlyCnhBFnZcFEEuYqbiUlNwWgMTdrZ3JbQFoEVG53rd8ztG9aPJMnBUQf/VFraBJeWnLS0RfjbKyLJA8FkT5seDYS1Qwyv8t0B/5C2ZmH2/eTGNNBgMmAAAAAElFTkSuQmCC",
+      "scale":1.5,
+      "show":true
+    },
+    "label":{
+      "fillColor":{
+        "rgba":[
+          0,255,255,255
+        ]
+      },
+      "font":"11pt Lucida Console",
+      "horizontalOrigin":"LEFT",
+      "verticalOrigin":"CENTER",
+      "text":"Toulouse Frame",
+      "show":true
+    },
+    "position":{
+      "interval":"2022-01-17T12:00:00Z/2022-01-17T13:00:00Z",
+      "cartesian":[
+        4624415.12018318,116587.90809901741,4376399.285187051
+      ]
+    }
+  },
+```
+
+# Properties 
+
+**id** - String : Identification of the CZML ground station
+
+**name** String : Name of the CZML ground station
+
+**availability** - [TimeInterval](https://cesium.com/learn/cesiumjs/ref-doc/TimeInterval.html) : Time interval where the CZML ground station is displayed.
+
+**description** - String : An optional description of the satellite, *default* : "Nameless ground station".
+
+**billboard** - [Billboard]() : A 2D object that allows to display a given image to represents the ground station. _default_ : A 2D image representing a ground station will be used.
+
+**position** - [Position]() : The position in a given frame of the ground station
+
+## Intrinsinc arguments
+
+These arguments can be used to build a CZML ground station object :
+
+**groundStation** - [GroundStation](https://www.orekit.org/site-orekit-development/apidocs/org/orekit/estimation/measurements/GroundStation.html) : An Orekit Ground station object
+
+**topocentricFrame** - [TopocentricFrame](https://www.orekit.org/site-orekit-development/apidocs/org/orekit/frames/TopocentricFrame.html) : An Orekit Topocentric Frame object
+
+# Build
+
+The CZML ground stration object can be build with :
+
+* A name, an id, an availability, a description, a position, a billboard :
+```Java
+CZMLGroundStation groundStation = new CZMLGroundStation(name, id, availability, position, billboard);
+```
+
+* An [Orekit groundStation](https://www.orekit.org/site-orekit-development/apidocs/org/orekit/estimation/measurements/GroundStation.html), a [Header](Header) :
+```Java
+CZMLGroundStation groundStation = new CZMLGroundStation(groundStation, header);
+```
+
+* An [Orekit TopocentricFrame](https://www.orekit.org/site-orekit-development/apidocs/org/orekit/frames/TopocentricFrame.html), a [Header](Header) : 
+```Java
+CZMLGroundStation groundStation = new CZMLGroundStation(topocentricFrame, header);
+```
+
+* A List<[TopocentricFrame](https://www.orekit.org/site-orekit-development/apidocs/org/orekit/frames/TopocentricFrame.html)>, a [Header](Header) : 
+(**This function can create several groundStation, with each topocentricFrame assigned to each station**)
+```Java
+CZMLGroundStation groundStation = new CZMLGroundStation(topotcentricFrameList, header);
+```