WYN-1001 - Celestial Navigation Tables and Sight Reduction Worksheets

Living Document Notice
Staged 2026-09-28. Living revisions and interconnected notes live in the Bosun PKM Garden.

Celestial Navigation Tables and Sight Reduction Worksheets

Performing celestial navigation sight reductions using sextant altitude measurements, nautical almanacs, and Pub. No. 229/249 tables requires rigorous calculation workflows. Wayfinder structures celestial navigation dossiers around durable Markdown spreadsheets and sight reduction logs.

Celestial Invariants

1. Sextant Altitude Correction: Observed sextant angles ($Hs$) factor index error, dip, refraction, and semidiameter to yield true altitude ($Ho$).
2. Computed Altitude and Azimuth: Intercept method (St. Hilaire) calculations determine computed altitude ($Hc$) and azimuth angle ($Zn$).
3. Intercept and Intercept Line Plots: Comparing $Ho$ versus $Hc$ plots lines of position (LOP) across Traverse spatial charts.

Structured celestial navigation worksheets ensure absolute backup positioning when electronic satellite systems fail.

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• Directus Target: wayfinder-blog
• Garden Source Reference: MOC - Wayfinder Navigation Engine, MOC - Traverse Spatial Engine, TRV-1001 - Offline Spatial Data