HORIZON

[xavier]

Fom the waters edge,how far out to sea can I see before the earths curvature takes effect and I can only see sky. I am assuming it is a clear day and I am using a telescope etc.

[wildwood]

If you're of average height, about 4 miles.

[Quizmonster]

If you're standing at the water's edge, the horizon is about 3 miles away. If you click here, that will link you to a web-page which has a handy computer system that helps you work it out. All you do is put the height of your eye into the slot and click on 'Compute'. So, if you're eyes are 5 ft 6 inches above the ground - ie 5.5 ft - put that into the slot. If you are standing on a 100 ft cliff, put 105.5 in.