About using this interface

This interface enables one to plot and list heliocentric orbit information for spacecraft remote from Earth and for planets having heliophysics spacecraft in orbit about them. The object(s) of interest, time span, time resolution (daily or lower) and coordinate system (solar ecliptic, inertial and rotating heliographic)are specified by users.
Underlying data files contain heliocentric distances and elevation and longitude angles at daily resolution. Plot options include object-specific time series plots of the radial distance and direction angles, as well as X-Y, X-Z, and Y-Z projections of the heliocentric position vectors.

In addition, one may plot and list position differences between any two objects as (a) time series of the differences between the radial distances and each of the two direction angles and (b) X-Y, X-Z, and Y-Z projections of the separation vector between the two objects.

These orbital codes were written to support multi-spacecraft studies of solar wind and cosmic ray phenomena; accuracy is tailored to facilitate these studies only. Radial distances should be good at an accuracy of 1%, and angles at 0.1 degree.
Note: sometime it may cause small non-smoothing (spikes) data in calculatin of XYZ-trajectoies More accurate data may be available at the JPL (Pasadena,CA) at https://ssd.jpl.nasa.gov/horizons/app.html#/ and US Naval Observatory, Washington, DC.

If you have any questions/comments about HelioIWeb service, contact: Dr. Natalia Papitashvili, Space Physics Data Facility, Mail Code 672, NASA/Goddard Space Flight Center, Greenbelt, MD 20771