Celestial navigation glossary
Pub. 249
Sight reduction tables for air navigation: Hc, d and Z for whole-degree latitude, LHA and declination.
Where the course teaches it
Reading Pub. 249, in the module The intercept method. Reduce a Sun sight with Pub. 249 or by formula on a calculator: Hc, Zn and the intercept.
Taught alongside it
- Navigational triangle
- Pole, zenith and GP on the celestial sphere: solving it gives Hc and the azimuth.
- Azimuth angle (Z)
- The tables’ angle at the zenith, turned into Zn by the rules printed on each page.