pray-calc/.github/wiki/api/functions/solarEphemeris.md

pray-calc v2.1.1

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pray-calc / solarEphemeris

Function: solarEphemeris()

solarEphemeris(jd): SolarEphemeris

Defined in: getSolarEphemeris.ts:46

Compute solar declination, Earth-Sun distance, and ecliptic longitude from a Julian Date. Accuracy: ~0.01° for declination, ~0.0001 AU for r.

Parameters

jd

number

Julian Date (use toJulianDate to convert a JS Date)

Returns

SolarEphemeris

Solar ephemeris data: declination (degrees), Earth-Sun distance (AU), and ecliptic longitude (radians, 0-2π season phase)

Example

const jd = toJulianDate(new Date('2024-06-21'));
const { decl, r, eclLon } = solarEphemeris(jd);