[AstroPy] Using astropy.time for 'deep time'?

[wbpython]

Hello,

I'm doing plots of planetary and spacecraft positions using a modern ephemeris.  However, as part of these plots, I want to show planet trails going back 100 years or more for outer planets and Kuiper Belt objects.

I've tried using astropy.time to define dates going back 100 years or more but it seems to not work, or at least not match the documentation.

In the documentation, it states that time has sufficient precision for nano-second accuracy over the age of the universe.  It seems like it should be adequate for these types of 'deep time' computations, unless this full range is not implemented.

Has anyone used astropy.time as a time-keeper for extremely long time computations that need connection to modern time systems?

Thanks,
Tom