I don't think I've ever seen it expressed this way before.
_Howard Admin
Posts : 8734 Join date : 2013-01-16 Age : 79 Location : California
Subject: Re: 8 inches per mile Tue Sep 12, 2017 10:39 am
I haven't seen that one either. Here's another way of looking at it.
For an observer on the ground with eye level at h = 5 ft 7 in (1.70 m), the horizon is at a distance of 2.9 miles (4.7 km).
I would have thought it was much farther.
NoCoPilot
Posts : 20293 Join date : 2013-01-16 Age : 70 Location : Seattle
Subject: Re: 8 inches per mile Tue Sep 12, 2017 10:49 am
With these simple mathematical tools one could pretty easily calculate the circumference of the earth, from watching a sailing ship of known height disappear over the horizon.