# How do you measure the tilt of the earth?

Jul 7, 2016

At summer solstice (about June 22) noon, if your height is h, shadow length is l and your are at latitude ${\theta}^{o} N$, the tilt angle is ${\left({\tan}^{- 1} \left(\frac{l}{h}\right) - \theta\right)}^{o}$.,

#### Explanation:

The angle of incidence of light rays for latitude ${\theta}^{o} N$ varies

periodically, over a year as period, from

'$\theta$+ tilt angle', at noon on summer solstice (about June 22) to

'$\theta$- tilt angle', at noon on winter solstice (about December 21),

and back to

'$\theta$+ tilt angle', for the next summer solstice.

Use, tan (angle of incidence of solar rays)=(length of the