Noon Latitude

MARITIME – CELETIAL NAVIGATION CALCULATOR Noon Latitude A precise tool.
πŸ“–
What is the Noon Latitude & How does it work?
At local apparent noon the Sun reaches its highest point on the meridian. The observed altitude of the Sun at this instant, after applying the necessary corrections, is called the corrected noon altitude (Ho). By comparing Ho with the Sun’s declination (Ξ΄) from the nautical almanac, a navigator can determine the vessel’s latitude. Two principal corrections are applied to the raw sextant altitude. The dip correction accounts for the observer’s eye height above sea level and is approximately 0.0293β€―Γ—β€―βˆšh minutes of arc, where h is the height in metres. Atmospheric refraction lifts the apparent Sun and is subtracted; it is usually taken from a refraction table and expressed in minutes of arc. When the Sun is north of the zenith (common in the Northern Hemisphere), the latitude (Ο†) is obtained from the simple meridian‑passage formula:
\phi = \delta + (90^{\circ} – H_{o})
\phi = latitude, \delta = Sun declination, H_{o} = corrected noon altitude
βš™οΈ
Parameters
Result β€”
❓
Frequently Asked Questions
What is local apparent noon in navigation?
Local apparent noon is when the Sun reaches its highest point on the meridian, directly overhead.
How do I determine the corrected noon altitude (Ho)?
The corrected noon altitude is obtained by applying necessary corrections to the raw sextant altitude of the Sun.
What is the purpose of dip correction in navigation?
Dip correction accounts for the observer’s eye height above sea level, adjusting the observed altitude of celestial bodies.
Where do I find the Sun’s declination?
The Sun’s declination can be found in the nautical almanac, which provides essential astronomical data for navigation.
How does the corrected noon altitude help determine latitude?
By comparing the corrected noon altitude (Ho) with the Sun’s declination (Ξ΄), navigators can calculate their vessel’s latitude.
What is the approximate value of dip correction per nautical mile?
The dip correction is approximately 0.029 degrees per nautical mile of eye height above sea level.
Why is it important to use the corrected noon altitude for latitude calculation?
Using the corrected noon altitude ensures accurate determination of latitude by accounting for various observational errors and atmospheric conditions.

Results are for informational purposes only and do not constitute professional advice.