Criteria for choosing SGP4/SDP4 in TLEPropagator?

Hi everyone,

I want to know which propgator using in TLEPropagator (SGP4 or SDP4).
A well-known criterion for selecting TLE propagator between SGP4 and SDP4 is the orbital period (225 minutes).
TLEPropagator in Orekit seems automatically select the model.
Does it follow the criterion of the orbital period?

Thanks in advance.

Hi,

Yes, the choice of the model is automatically handled by Orekit.
You can see this criterion on the TLEPropagator class, between lines 284 and 289.
On line 284, the satellite’s orbital period is computed using the satellite’s mean motion (n = 2*pi/T).

Best regards,
Bryan

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Thank you Bryan!