XALEN Ephemeris API Guide: NASA-Grade Calculations

What is XALEN Ephemeris?

XALEN Ephemeris is our own high-precision astronomical engine, open-sourced as XALEN Ephemeris (Apache-2.0). It computes planetary positions from NASA Jet Propulsion Laboratory (JPL) ephemeris data and is validated against JPL DE440 across millions of test charts. Vedika API runs it on our servers, giving you access via simple REST calls without needing local ephemeris files.

Why Use an API?

Get Planetary Positions

// Get planetary positions for a specific moment
const response = await fetch('https://api.vedika.io/v2/astrology/planet-positions', {
    method: 'POST',
    headers: {
        'Content-Type': 'application/json',
        'Authorization': 'Bearer YOUR_API_KEY'
    },
    body: JSON.stringify({
        datetime: '2026-03-01T10:30:00',
        latitude: 28.6139,
        longitude: 77.2090,
        timezone: '+05:30'
    })
});

const { data } = await response.json();
console.log(data.planets);

// Response (data, trimmed to Sun and Moon):
// {
//     "ayanamsa": { "id": 1, "name": "Lahiri", "value": 24.218707 },
//     "planets": [
//         {
//             "id": 0,
//             "name": "Sun",
//             "sign": "Aquarius",
//             "house": 10,
//             "degree": 16.4,
//             "longitude": 316.4,
//             "speed": 1.0035704732546264,
//             "isRetrograde": false,
//             "nakshatra": { "name": "Shatabhisha", "lord": "Rahu", "pada": 3 }
//         },
//         {
//             "id": 1,
//             "name": "Moon",
//             "sign": "Cancer",
//             "house": 3,
//             "degree": 17.78,
//             "longitude": 107.78,
//             "speed": 13.821538265830895,
//             "isRetrograde": false,
//             "nakshatra": { "name": "Ashlesha", "lord": "Mercury", "pada": 1 }
//         }
//         ... Mars, Mercury, Jupiter, Venus, Saturn, Rahu, Ketu
//     ]
// }

Supported Celestial Bodies

Ayanamsa Options

import { VedikaClient } from '@vedika-io/sdk';

const vedika = new VedikaClient({ apiKey: process.env.VEDIKA_API_KEY });

// Sidereal (Vedic) positions: /v2/astrology routes use the Lahiri ayanamsa,
// and the response reports the ayanamsa value it applied
const sidereal = await vedika.post('/v2/astrology/planet-positions', {
    datetime: '2026-01-15T12:00:00',
    latitude: 28.6139,
    longitude: 77.2090,
    timezone: '+00:00'
});
console.log(sidereal.ayanamsa);

// Tropical (Western) positions come from the Western routes
const tropical = await vedika.post('/v2/western/transit-positions', {
    datetime: '2026-01-15T12:00:00',
    latitude: 28.6139,
    longitude: 77.2090,
    timezone: '+00:00',
    transitDateTime: '2026-01-15T12:00:00'
});
console.log(tropical.planets.map(p => `${p.name}: ${p.sign.name} ${p.degree}`));

House Calculations

// Get house cusps for a location
const houses = await fetch('https://api.vedika.io/v2/astrology/houses/koch', {
    method: 'POST',
    headers: {
        'Content-Type': 'application/json',
        'Authorization': 'Bearer YOUR_API_KEY'
    },
    body: JSON.stringify({
        datetime: '2026-01-15T12:00:00',
        latitude: 28.6139,
        longitude: 77.2090,
        timezone: '+00:00'
    })
});

// One route per house system: /v2/astrology/houses/koch, /whole-sign,
// /equal, /campanus and /regiomontanus (plus /v2/astrology/house-cusps)

// Response (data) includes:
// - system and systemCode
// - cusps: 12 entries with house, cuspDegree, sign and degreeInSign
// - ascendant
// - midheaven

Accuracy Comparison