Table of Contents

Latitude

Contrary to popular belief, latitude is not actually slicing the earth like a tomato, but it’s actually measuring angles from the center of the earth.

1 Degree Lat = 60 Minutes= 60 miles

Sextant

Using a sextant, you measure the height of a star above the horizon. Using the Nautical Almanac, you get the longitude and latitude of the Ground Point (the location directly below the star.) Then, you get the difference between the angle of the Height Sextant \(H_{S}\) and the ground point (vertical) at your location (\(90 - H_{S}\)). This angle is equivalent to the latitudinal distance from your location to the ground point of the celestial body you chose. For example, if it’s 3 degrees, then that’s 180 nautical miles away.

SeattleHawaiiHsground point (gp) of star(Height Sextant)90-Hs90-Hs90-Hs

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