Solar System Ephemerides and Orbital Data from JPL

The JPL HORIZONS service provides access to ephemeris computation and orbital data for over 561,000 asteroids, 3,000 comets, 171 planetary satellites, 8 planets, and other solar system objects. It is maintained by the Jet Propulsion Laboratory's Solar System Dynamics Group for generating highly accurate positional predictions.

Use Cases

• Compute ephemerides for specific asteroids or comets to plan astronomical observations.
• Generate orbital data for planets and their satellites for spacecraft trajectory analysis.
• Access barycenter data for the solar system to support celestial mechanics research.
• Retrieve positional data for Lagrangian points (L1, L2) for mission planning.

Strengths

• Covers a large catalog of over 561,000 asteroids and 3,000 comets.
• Provides ephemerides for 8 planets, 171 planetary satellites, and system barycenters.
• Maintained by the authoritative JPL Solar System Dynamics Group.

Limitations

• Data is provided via an online service (HTML/Telnet), not as a static downloadable dataset.
• The specific data schema (columns) and sample data are not documented in this entry.
• Access requires using the HORIZONS web interface or API, which may have a learning curve.

Provenance

Source

Jet Propulsion Laboratory, Solar System Dynamics Group, NASA.

Collection Method

Online ephemeris computation service generating data from orbital models.

Freshness

The service entry was last updated in March 2026, indicating active maintenance.

Geography

Solar system.