Sky

Featured Video Play Icon

The sky appears practically identical to all observers on Earth, except that the Earth obstructs the view to a different part of the sky to a different observer on Earth, and daylight obscures the view to most objects in the sky.

The fact that the sky appears identical everywhere on Earth can only be adequately explained if all the astronomical objects are very far from us and that the Earth is a sphere.

Only the Moon and artificial satellites are close enough to Earth that two different observers on Earth see these objects in a different location in the sky at the same time. The planets can be seen moving against distant stars over time, but at the same time, all observers on Earth see the planets at the exact location. The reason is that the planets are very far compared to the size of Earth, but not nearly as far as the stars.

References