In the context of astronomical triangles, which sides are specifically defined?

In the study of astronomical triangles, the specific sides that are defined are declination and zenith distance. Declination refers to the angle that an astronomical object is located relative to the celestial equator and is analogous to latitude on Earth. Zenith distance, on the other hand, is the angle between the object being observed and the zenith, which is the point directly overhead of an observer.

In the context of astronomical observations, the declination and zenith distance are crucial for locating stars and other celestial objects in the sky. These components are essential for calculating various astronomical phenomena and are integral in the practices of navigation and positioning.

Understanding the relationship between declination and zenith distance allows astronomers and navigators to accurately determine their position on Earth and the position of celestial bodies in the astronomical sphere. This makes it clear why this choice is the most relevant in the context of astronomical triangles.