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

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[**pray-calc v2.1.1**](../README.md)
***
[pray-calc](../README.md) / solarEphemeris
# Function: solarEphemeris()
> **solarEphemeris**(`jd`): `SolarEphemeris`
Defined in: [getSolarEphemeris.ts:46](https://github.com/acamarata/pray-calc/blob/4227afc2c3993234794b3a1a561c080edc6d4d4e/src/getSolarEphemeris.ts#L46)
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
```ts
const jd = toJulianDate(new Date('2024-06-21'));
const { decl, r, eclLon } = solarEphemeris(jd);
```