# Angle Between Ecliptic and Horizon

The angle between the ecliptic and the horizon is given by the equation below:

\begin{align*} \cos I = \cos \epsilon \sin \phi - \sin \epsilon \cos \phi \sin \theta \end{align*}
$$\epsilon$$ is the obliquity of the ecliptic (e.g. 23.4°), $$\phi$$ is latitude, $$\theta$$ is the Local Sidereal Time.