Talk:Length of day

Proposed material

Length of day is calculated by

$\cos H_{0}={\frac {\sin(-0.8333^{\circ })-\sin \delta \sin \varphi }{\cos \delta \cos \varphi }}$

$\delta$ is the Sun's declination

$\varphi$ is the geographical latitude

$H_{0}$ is an angle between 0° and 180°

If $\cos H_{0}$ is less than −1 then the Sun is circumpolar.

If $\cos H_{0}$ is greater than +1 then the Sun is down all day.

Divide $H_{0}$ by 360°. Then multiply by 24 hours. Then multiply by two. This last result is the length of day (hours).

Sources

Iceblock (talk) 04:42, 29 January 2015 (UTC)