Non-LEO orbits do not properly display

[CelesTrak]

Orbital ring graphics do not properly display for orbits other than LEO. MEO orbits display as partial arcs and GEO orbits only show dots (see attached image).

The orbital periods are correct coming out of SGP4 and into satrecs. The issue appears to be a time restriction (~90 mins) somewhere within the graphics potion of the application. Thus, the LEO orbits display correctly (90 mins), the MEO orbits only show partial arcs (90 mins of a longer period), and GEO orbits (24-hour Period) only show a dot.

[thkruz]

Take a look at https://github.com/Flowm/satvis/blob/master/src/modules/SatelliteProperties.js#L153

It sounds like you aren't passing it forward and backwards propagation parameters so it is defaulting to LEO.

[Flowm]

Thanks for reaching out!

To be honest I've mostly focused on LEO satellites in the past as theses are the ones I'm actively involved with. The reported behavior is a combination of two things:

• GEO satellites not having an orbit line at all:
  Some entities (like the Sensor Cone) are intended/optimized for LEO satellites, so they were disabled for all satellites with an orbital period >12h.
  -> As at least the Orbit visualizations still makes sense for GEO satellites I adjusted the filter to enable the orbit for GEO satellites.

• MEO/GEO satellites not showing a full orbit:
  As identified by @thkruz this stems from the fact, that the orbit line is based on a propagated position interpolated by the cesium framework. In this the sampling steps for propagation were hard-coded.
  -> The new version is now calculating the sampling steps (along with the sampling interval for performance reasons) based on the orbital period as suggested.

A fixed version is now available in the next branch and live on satvis.space/next. This is the branch where I have been working on some refactoring of the surrounding framework (vue3 upgrade, proper state management in the url) on and off for the past half year with the plan to merge it to the main branch in the near future.

Please reach out if there are any further questions or if I can assist the process of providing a cesium based visualization again on celestrak.org in any way 🙂

[CelesTrak]

Florian,

Thank you! We have forward the info you posted to our volunteer working this section.

We have a list of items we are working on, sent you a direct email for another issue we are addressing.

[CelesTrak]

tagging @justinweaver1