openephemeris-api-reference

Access OpenEphemeris API endpoints for astronomical and astrological computations.

3|Updated Mar 19, 2026

Search Tags:#api #mcp #astrology #astronomy #ephemeris #jpl

Ready to run

npx skills add https://github.com/openephemeris/openephemeris-MCP --skill openephemeris-api-reference

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: openephemeris-api-reference
Source: https://github.com/openephemeris/openephemeris-MCP/tree/main/skills/openephemeris-api-reference
Command: npx skills add https://github.com/openephemeris/openephemeris-MCP --skill openephemeris-api-reference

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

This skill provides a comprehensive interface for accessing high-precision astronomical data and astrological computations, eliminating the need for manual lookups or error-prone calculations.

Core Features & Use Cases

Astronomical Computation: Access 118 endpoints covering ephemeris, ACG, synastry, and predictive astrology powered by NASA JPL DE440 data.
Workflow Integration: Standardized procedures for location, timezone, and birth data handling ensure zero-hallucination results.
Use Case: Use this skill to generate a natal chart, calculate planetary transits, or perform astrocartography analysis for a specific location and time.

Quick Start

Use the openephemeris-api-reference skill to calculate a natal chart for a person born on April 15, 1990 at 2:30 PM in Chicago.

Frequently Asked Questions about openephemeris-api-reference

High-intent search queries and answers about installing and using this skill.

FAQPage Schema

How do I calculate a natal chart using JPL ephemeris data?▼

You can calculate a natal chart by providing birth date, time, and location to the API endpoints powered by NASA JPL DE440 data, which ensures high-precision planetary positions without manual calculations.

What astronomical computations are available for astrocartography and transit analysis?▼

The API provides 118 endpoints for astronomical computations including astrocartography (ACG), planetary transits, synastry, and predictive astrology, all driven by standardized location and timezone data handling.

Can I use this ephemeris API for professional research applications?▼

Yes, the API is designed for professional and research applications, facilitating complex chart generation, transit analysis, and location-based celestial mapping with zero-hallucination results through strict endpoint schemas.

Does the API require specific access protocols for full ephemeris functionality?▼

Yes, full functionality requires adherence to specific endpoint schemas and tier-gated access protocols to retrieve high-precision astronomical and astrological computation data across all 118 available endpoints.

What's the best way to integrate birth data handling for synastry chart generation?▼

Use the standardized procedures for location, timezone, and birth data handling provided by the API to ensure accurate synastry chart generation and zero-hallucination results in your workflow integration.

Why does location-based celestial mapping need standardized timezone procedures?▼

Standardized timezone and location procedures are required to ensure zero-hallucination results when performing location-based celestial mapping, as precise coordinates and times are essential for accurate JPL DE440 ephemeris calculations.