How does trigonometry relate to astronomy?

Trigonometry is a branch of mathematics that deals with the study of the properties of a triangle. The sides and angles of a triangle are related to each other through the use of different trigonometric functions. 

Further, astronomy is the branch of science that deals with the heavenly or celestial bodies. Apparently, in most cases, if we are to determine the distances between them, we require the use of the trigonometric functions for the proper measurement. 

Also, we are able to predict the proper movement of the celestial bodies based on the projected sides of triangles. 

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