Satellite position over time paths not showing

CesiumJS
1

I have an application where I’m propagating several satellites using the satellite.js library. The satellite orbits seem to be good and I can generate paths for all satellites except for GEO satellites.

This is how my entity looks:

let entity = this.viewer.entities.add({
      position: undefined,
      point: {
        pixelSize: 4,
        color: Cesium.Color.YELLOW
      },
      path: {
        width: 1,
        material: Cesium.Color.YELLOW,
        trailTime: 1,
        leadTime: 1000,
        show: true
    },
 })

Then I loop through some time steps and propagate the path of the satellite (using satellite.js and satellite TLEs) for x amount of time in front of the satellite so I can show the path.

let positionAndVelocity = satellitejs.propagate(satRec, nextStepDate);
const gmst = satellitejs.gstime(nextStepDate);
const position = satellitejs.eciToGeodetic(positionAndVelocity.position, gmst);
let debrisPos = Cesium.Cartesian3.fromRadians(position.longitude, position.latitude, position.height * 1000);
entity.position.addSample(nextStepJulianDate, debrisPos);

It seems like this happens for the GEO satellites specifically because the satellites are not actually moving across the earth (or very little), and are basically above the same spot all the time.

How can I get orbit paths to show for all of my satellites?

Here is an example of what my application looks like. The GEO satellite is out to the right that does not have a path

image
image1544×482 112 KB

2

@wiatrp

Welcome to the community! If I am not mistaken, it seems like this question is strictly related to satellite-js.

Is that correct? If so, you will receive the best support if you consult with their development team. If this is in fact a CesiumJS related question, I would love to see a sandcastle demo of what you have so far. This would help me debug the problem.

Best,
Sam

3

What happens if you show 24 hours of orbit instead of what looks like 20 minutes or so for the LEOs? Can you also show the CesiumJS code you are using to configure the satellites?

4

@scottUFR

I am not sure exactly what you are trying to get at here. Could you maybe give me a little bit more information on your use case? Are you referring to this sandcastle demo?

Looking forward to hearing more.

Best,
Sam