Sight reduction

Celestial navigation - Astronavigation

Sight reduction:

- Marcq Saint Hilaire Line of Position, intercept method (p=Ho-Hc, Zn)

- Input for observed altitude Ho or instrumental Hs (Nautical Almanac data needed for the Sun and the Moon)

- Calculator for Intercept method (p=Ho-Hc, Zn) altitude Hc and azimuth Zn

- Running fix

- Plots up to 3 Marcq Saint Hilaire Lines of Position on Google maps

- Local hour angle (LHA)

- List of navigational stars

- Logbook (output is copied to clipboard)

- New optimized user interface

- GNSS fix to check the solution

Sight reduction is the process of deriving from a sight the information needed for establishing a line of position.

This app is a calculator to get the intercept from the assumed position of the observer AP(latitude, longitude), the geographical position of the celestial body observed, GP(Dec, GHA), and its corrected altitude Ho.

Manual and examples in the developer's website.

Ref: https://en.wikipedia.org/wiki/Sight_reduction

User interface:

- Zoom buttons +/-

- Map types: standard, terrain, and satellite

- GPS location. ("Location" App permission must be allowed. Switch on you GPS, and then automatic location detection is possible)