Question

The point on the celestial sphere exactly below the observer's feet is called________.

• A. nadir
• B. zenith
• C. meridian
• D. south pole

Answer 1

The correct option is A nadir

The celestial sphere is an imaginary sphere on which all the celestial bodies lie and the observer is considered as the center of the sphere.
The point on celestial sphere exactly above observer's head is called zenith. Nadir is a point on celestial sphere directly underfeet of the observer.