# Symbols:Z/Zenith Distance

Jump to navigation
Jump to search

## Zenith Distance

- $z$

Let $X$ be the position of a star (or other celestial body) on the celestial sphere.

The **zenith distance** $\zeta$ of $X$ is defined as the angle subtended by the the arc of the vertical circle through $X$ between $X$ and the zenith.

It is often denoted by $z$.

## Also denoted by

The zenith distance is also seen denoted by the Greek letter $\zeta$.

## Sources

- 1976: W.M. Smart:
*Textbook on Spherical Astronomy*(6th ed.) ... (previous) ... (next): Chapter $\text {II}$. The Celestial Sphere: $18$.*Altitude and azimuth.*