getMoonSightingReport

moon-sighting v1.1.1

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moon-sighting / getMoonSightingReport

Function: getMoonSightingReport()

getMoonSightingReport(date, observer, options?): Promise<MoonSightingReport>

Defined in: api/index.ts:306

Compute a complete moon sighting report for a date and location.

Returns all quantities needed for Islamic crescent sighting determination: sunset/moonset times, best observation time, crescent geometry (ARCL, ARCV, DAZ, W, Lag), Yallop category, Odeh zone, and plain-language guidance.

Requires initKernels() to have been called first (or pass kernels in options).

Parameters

date

Date

Date to check (UTC midnight or any time on that civil day)

observer

Observer

Observer location and environmental parameters

options?

SightingOptions

Optional configuration for refraction model, best-time method, etc.

Returns

Promise<MoonSightingReport>

Complete MoonSightingReport

Example

await initKernels()
const report = await getMoonSightingReport(new Date('2025-03-01'), {
  lat: 51.5074, lon: -0.1278, elevation: 10, name: 'London'
})
console.log(report.yallop.category)  // 'A' through 'F'
console.log(report.guidance)         // "Best time to look: ..."