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We have collected formulae relevant for the transformation
between planetocentric and heliocentric coordinate systems
and determined the precision of these transformations
for the period 1950-2060, most relevant for space science.
We give a very short but complete description
of orbit determination from Keplerian orbital
elements.
With the simple set
of formulae given in this paper (and adapted from
Simon et al. (1994)) the positions of the inner planets
can be determined to though for the Earth
this precision can be increased to .
Adding disturbance terms from Simon et al. (1994)
increases the precision to . This sets
the limits for the precision to be achieved
by a single set of Keplerian elements. For higher precision
the installation of an integrated ephemeris
is recommended.
We also determined Keplerian orbital elements for
major interplanetary spacecraft within the precision
limits given by the NSSDC data source. These
allow quick approximate calculations of
spacecraft positions and also allow to
cross check existing position data sets.
Formulae
given in this paper can easily be implemented
in software. Programs used in preparation
of this paper have been written in the
IDL language and are available from
our website
^{24}.

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** Up:** Heliospheric Coordinate Systems
** Previous:** Spacecraft Elements
Markus Fraenz
2017-03-13