When using Orekit for orbit prediction with an atmospheric drag model, the predicted orbit 10 days out shows a 6-second difference compared to STK

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@Sohnny I just thought of something. The NRLMSISE00 model has a bunch of switches, and turning them on/off can vary the drag result by km. I run NRLMSISE00 with switch 9 set to -1 and switch 1 set to 1:

NRLMSISE_CSSI_MODEL = NRLMSISE00(
    CSSI_WEATHER_MODEL,
    CelestialBodyFactory.getSun(),
    EARTH_BODY
).withSwitch(9, -1).withSwitch(1, 1)

Which as far as I can tell is the most high-fidelity way to run it. If you have different switch settings on in STK vs. Orekit you’d get very different results.