Category:Celestial Horizon

This category contains results about Celestial Horizon.
Definitions specific to this category can be found in Definitions/Celestial Horizon.

The celestial horizon is the great circle on the celestial sphere whose plane is perpendicular to the line from the zenith to the observer.

Thus the celestial horizon is the edge of the visible part of the celestial sphere.

The rest of it is hidden by Earth itself.