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11.2: Finding Latitude with the Pole Star

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    Imagine yourself standing at night at point P on Earth and observing the pole star (or better, the position of the north celestial pole, near that star), at an elevation angle \(\lambda\) above the horizon.

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    Figure \(\PageIndex{1}\): The angle of the pole star above the horizon equals the local latitude.

    The angle between the direction of the pole and the zenith is then 90−\(\lambda\) degrees. If you continue the line from zenith downwards it reaches the center of the Earth, and the angle between it and the Earth's axis is also 90−\(\lambda\).

    Therefore, as the accompanying figure shows, \(\lambda\) is also your latitude.

    This page titled 11.2: Finding Latitude with the Pole Star is shared under a CK-12 license and was authored, remixed, and/or curated by CK-12 Foundation via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.

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