ephemsys is a service of the IMCCE's Virtual Observatory project
allowing the computation of the positional ephemerides of the components of asteroidal systems.
The service can be used as a Web service and easily integrated into your own software (cf.
Miriade.ephemsys main page). We propose some examples
of client programs for that. The service can also
be used through a Web form which allows to define
your input parameters, and to submit requests. This page describes how to do with some of the
input parameters of the service.
The orbital elements of the components of asteroidal systems are determined by fitting the available
astrometric observations with the Genoide algorithm (Vachier et al. 2012, A&A 543). The specific interface
of Miriade.ephemsys service allows to retrieve the list of asteroidal systems for which ephemerides can
be computed, as well as the list of orbital solutions available for a given asteroidal system. The celestial positions
of the asteroidal system barycenters are computed from their orbital elements provided by the
ASTORB database of the Lowell Observatory.
The celestial positions of planets are computed with the IMCCE's INPOP
4-D planetary theory.
The period of time covered by Miriade's ephemerides of asteroidal systems depends on systems. Use the
specific interface (gensol keyword)
to get the start and end date of availability of ephemeris computation.
The dynamical properties of asteroidal systems are updated each time we get new astrometric observations of systems to improve their orbital solutions.