Info request on Ephemeris/TimeInterpolator

No problems, this is just a general information request on the behavior of a couple of classes. I am going to be creating an Ephemeris object from a list of time/position/velocity/covariance values that I am generating from raw orbit data and a custom kalman filtering process. My raw data set covers approximately 24 hours at 30 second intervals. The only issue is, there are a few places in my data where I have small gaps (ranging from 30 seconds to about 10 minutes in the worst case) because of bad/nonexistent raw GPS information.

I just wanted to ask - can the Ephemeris class handle interpolating between uneven time gaps? And assuming extremely accurate orbit data for the given data points, about how much bigger would a time gap have to be than the default 30 seconds to start causing issues in satellite position accuracy?

Yes. It uses a full hierarchy of TimeInterpolator in order to manage the various components of the SpacecraftState (all types of orbit, attitude, additional states). Underneath, these interpolator ends up using Hipparchus HermiteInterpolator, whi can handle irregular samples.

I don’t know about the accuracy you will get depending on the size of the gap. What is constant is the number of points used in the interpolation, so if you have a gap, the interpolator will need to pick up points from farther away to complete its sample.

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Great, thank you :slight_smile: