Question

why is the visibility of constellations affected by the observe's latitude but not the longitude

Answer 1

Answer:

They depend on latitude because your position on Earth determines which constellations remain below the horizon. They depend on time of year because Earth's orbit changes the apparent location of the Sun among the stars.

Answer 2

Answer:

The Earth is an irregularly shaped ellipsoid.

Answer 3

Answer:

The Earth is an irregularly shaped ellipsoid.