Eli5 how telescope works? How can you look at other planets and solar system but not new york from alasca?

Question

Eli5 how telescope works? How can you look at other planets and solar system but not new york from alasca?

In: Physics

Answer 1

You cannot see New York from Alaska because the earth is ball shaped. That means the surface of the earth is curved.

If there were no buildings in the way, the furthest you can see is called the horizon. After the horizon the surface drops down. The horizon is only about 3 or 4 miles away.

Obviously New York is a long long distance away so it is below the horizon. A telescope cannot see things beyond the horizon because it would be hidden.