This library is designed to access the binary planetary ephemeris files, such INPOPxx, JPL DExxx and SPICE ephemeris files.

This library provides a C Application Programming Interface (API) and, optionally, Fortran 77/2003, Python 2/3 and octave/Matlab interfaces to be called by the application.


This software is an open-source product distributed under three distinct licenses giving you the choice of one of the three following sets of free software/open source licensing terms. This allows the use of our code in as wide a variety of software projects as possible.

This software is governed by the CECILL-C, CECILL-B or CECILL version 2.1 license under French law and abiding by the rules of distribution of free software. You can use, modify and/or redistribute the software under the terms of the CeCILL-C, CeCILL-B or CeCILL license as circulated by CEA, CNRS and INRIA at the following URL


Latest stable version

  • Version 3.5.1 (February 2022)
    PyPI version Homebrew version Fedora package
    Vcpkg package ConanCenter package Octave package
    • Support the incremental assignment in the text SPICE kernel file (files .tpc).
    • Support the relative frames in the frame SPICE kernel file (files .tf).
    • Fix the returned values of calceph_getconstantvs with large SPICE kernels.
    • Fix random crash or double-free error when meta-kernel SPICE kernel files are closed (files .mk).
    • Raise an error inside the function calceph_compute if center != 0 for the target (14,15,16,17), to conform to the documentation.
    • Fix the object name Megaclite (519) from NAIFID_MAGACLITE to NAIFID_MEGACLITE.
  • Previous releases

Development version

The latest sources of the library are available using this gitlab repository.


Reference manuals


External tutorials are available for various languages.

  • Python interface
  • Octave/Matlab interface


The installation steps for various programming languages are described in the following links.

Other interfaces

The following interfaces for CALCEPH are available:


The library is written by the research team Astronomie et systèmes dynamiques (CNRS/Observatoire de Paris/IMCCE).

For all comments concerning these pages, contact the authors:

Last update Tuesday 19 July 2022