What is another word for visible horizon?
Pronunciation: [vˈɪzəbə͡l həɹˈa͡ɪzən] (IPA) 
The visible horizon refers to the line that separates the Earth's surface from the sky. It is the point where the Earth's curvature is apparent and where we can observe the sky meeting the ground. There are several synonyms for visible horizon, including apparent horizon, real horizon, and true horizon. The apparent horizon is the imaginary line that appears to be the boundary between the sky and the Earth's surface. The real horizon is the actual boundary between the two and is affected by the observer's height above sea level. The true horizon is the theoretical boundary between the Earth and sky, assuming no atmospheric refraction. Regardless of the terminology used, the visible horizon is an important reference point in navigation and astronomy.
