Look up current positions and velocities of solar system objects I am working on an orbital dynamics code and, for fun, I would like to model the Sun-Earth-Moon system with my code.  I can look up the masses of each object just fine, as well as average distances and relative velocities (which I can also calculate).  However, I would like to model the Sun-Earth-Moon system in great detail.  I would like to know the positions and velocities of each object on any given day (today works just fine) so that I can represent the orbits of these objects with great accuracy, hopefully even reproducing their actual ellipticity.  Where can I find values for:


current Sun-Earth distance
current Earth-Moon distance
current Sun-Moon angular separation
current velocity of Earth relative to Sun (or relative to Sun-Earth(-Moon?) center of mass)
current velocity of Moon relative to Earth


and, maybe even


current velocity of Sun relative to Sun-Earth(-Moon?) center of mass.


Is there any resource that provides these current values?
Is there any resource that provides these current values?


Yes. The JPL HORIZONS on-line solar system data and ephemeris computation service provides these values, and much more.