Final answer:
The angular distance from horizon to opposite horizon is 180 degrees, representing half of the celestial sphere's 360 degrees.
Step-by-step explanation:
From horizon to opposite horizon, the sky takes up an angular distance of 180 degrees. This is because astronomers measure the dome of the sky as part of a great sphere that envelopes the Earth.
While the entire celestial sphere consists of 360 degrees, the dome that we can see from one horizon to the other spans exactly half of this, constituting 180 degrees.
No matter what your latitude is, the angular distance from horizon to horizon remains the same; aspects such as the position of the celestial pole above the horizon change with latitude, but not the horizon-to-horizon angular distance.