is the curve of the earth perceptible by looking at the horizon?

Question

i need to know the circumpherence of the earth and also the angle of our field of vision i think we can see abot 90 degrees on each eye i also believe the horizon is about 4.7 km away so i will be able to conclude finally if the earths curve is visible or not and remember im talking about the horizon only i know its boring but i will win!!

Answer 1

The oldest way to prove that the earth's horizon is not flat is to do the old sailing ship on the ocean thing. The horizon IS curved, since the planet IS a ball floating in orbit around the sun. The way to see this is to watch a sailing ship either approaching or leaving. Better if it's approaching. You'll see the tops of the sails first, gradually seeing more and more of the ship as it approaches you.

Another way to determine the curve of the earth is to map the positions of various shadows (in different locations) at noon. If you map the shadow, or absence of a shadow of a skyscraper at noon, with the sun directly overhead, you're not going to get the same type of shadow mapped at from a skyscraper in another country or city far away from you (preferably one still experiencing daylight.) As for whether or not you can see the curve of the earth this way, the answer is no. But I HAVE actually seen the curve of the earth by watching the sun rise from a transatlantic flight. So if you really wanna see the Earth's curve...get on an airplane and go somewhere on the other side of the ocean.

The other stuff, such as the circumference of the earth...? Well, you'll have to look that one up yourself.

Answer 2

If you are on the surface of a perfect sphere (say on a boat in the middle of an ocean with no waves) you would not see the 'curvature of the sphere'

as you turned in a circle, you would believe you were in the exact center of a perfectly flat disk.

Even when you leave the surface of the sphere, you still see what can be best described as a flat disk when you look down upon it. (for example, when a photo from the space shuttle looks 'forward' you get the impression you can see the curvature of the earth. But if you were to take a wide angle photo straight down, you would still see just a circle.

Which sort of begs the question "what do you mean by 'the curvature' anyway?"

I think that boils down to "at what point does the horizon boundary between sphere and not-sphere appear to no longer be a perfectly flat line." and the answer to that would have to be as soon as you leave the surface of the sphere, getting more obvious the higher you go. But even as a six foot tall person, the horizon would not be perfectly flat. Though there are larger errors in the shape of your retina than that, so human perception of it at 6 foot altitude is probably unlikely.

Plus, of course, we don't live on a perfect sphere.

Answer 3

Yes - indirectly we can percieve the curve of the earth by noting on clear days, without atmospheric disturbance, that very tall buildings (or tall ships) are visible through a telescope from the top down. Knowing the height of the buildings, or ship's masts, and the distance between them and the observer, it is possible to estimate the circumference of the earth. The ancient Greeks knew all about this, and worked it out with amazing accuracy (Note however that it is impossible to measure with complete accuracy since the earth is not quite a true sphere, but has a slight equatorial bulge).

Answer 4

Circumfrence of Earth is 36,000 miles @ the Equator. On a very clear, dustless day yes you can see the curvature of the earth 27 miles from where you are standing, providing the area in front of you is flat. Also the higher you are the easier it is to see the curve. That's why if your in the crows nest of a ship you can see another ships mast before someone on the bow can see it.

P.S. Debster, it's the same guy asking the same question, and the answer he chose is wrong

Answer 5

The only place I think you will see it. Would be at Sea--or maybe on one of the Great Lakes. I've ben to both and as I recall you do have the Slightest feeling of seeing a curve to the Horizon away from shore.

Answer 6

At sea last year, on a calm day, the horizon seemed to me to have a visible curve. I found a long piece of wood with a straight edge, and held it out along the line where the sea met the sky. At each end of the wood, there was an appreciable gap between sea and the straight edge.

Answer 7

I haven't done the math, but yes, one can deduce the shape of the earth by looking at faraway horizons. The ancient Greeks knew the world was round thousands of years ago, because when they saw ships approaching on the horizon, the mast of the ship always appeared first.

Answer 8

Yes....the visible horizon at sea level is around 26 miles if you are lucky enough to spot a ship just beyond that distance you will only see an upper portion of it as the remainder is on the curvature of the earth and hence out of sight.

Answer 9

Maybe, we see the horizon so near BECAUSE the earth is curved

Answer 10

I can't see a curve from where I am standing.