5/1/14 C. Acton The planetary ephemeris DE432 has been developed expressly for the New Horizons project. As described in the IOM de432.pdf, the primary change is an update of the ephemeris of the Pluto system barycenter. For the other planets DE432 represents only a minor update compared with DE430. DE430 is still recommended for most users, if only because the documentation for DE430 is more thorough. The full de432 file (not provided on the NAIF server) covers the time frame from 1550 to 2650. A shorter file, de432s, covering only 1950 to 2050 is provided on the NAIF server.