I have often run into a problem, especially during some propagation, where the Ephemeris propagator doesn't have quite enough data to allow the underlying event detector sampler to get to where it needs to go. It doesn't happen often, but it's happened enough that I've considered looking at letting users of the library construct an Ephemeris object that has the option to allow extrapolation at the boundaries. My thought is that the default behavior would be to keep it exactly as it is now. I was going to add two additional constructors, one that simply has the flag that enables extrapolation and then another than allows the user to provide bounds on how much extrapolation on either side that is allowed. This way a user can't accidentally sample way outside of the ephemeris range but they can avoid an exception for a near in sampling.
Before confirming the add I was going to create test cases for LEO, HEO and GEO orbits and was going to see how fast the extrapolation degrades in accuracy for these standard orbits. Assuming that:
1. The default behavior stays the same
2. There is a rigorous unit test for the additional cases
3. User options are as defined above
Is this something that the community would like to have committed back to the main distribution?
Hank