A very rough or "ball park" figure is about 20 miles.
Comment: It depends on your height above the water. You could only see 20 miles if you were well above sea level.
If you are standing more or less at sea level, with your eyes just a few feet above the water level, you could see only about 3 or 4 miles. For example:
Eye level at 6 feet: horizon at about 3 miles.
Eye level at 24 feet: horizon at about 6 miles.
Eye level at 96 feet: horizon at about 12 miles.
Eye level at 270 feet : horizon at about 20 miles.
Depends on the weather and generally to the horizon
2 miles
Your at the equator if you see Polaris at the horizon
Ordinarily, the farthest visible big wave might be half a kilometer to a kilometer away. On a calm day, someone with eyes two meters above the water could see water out to the horizon, where his vision would be tangent to the Earths surface and at right angle to a radius. This makes a right angle with two sides of about 6371 kilometers and .002 kilometers greater. Using Pythagorus, horizon^2 + 6371^2 = 6371.002^2 so horizon = 5.048 km. There is a far simpler equation to arrive at a solution in miles, this it the square root of 1.5 times the height of a human above sea level (in feet), using the sum above, 2 meters (6'6") * 1.5= 9'9", the square root of which is 3.146 = 3.146 miles, 5.048Km = 3.136 miles, taking in to account that's the height of his eyes not his head, i would say this equation would suffice and is far simpler and easier to remember.
Depends on the height of the aircraft above ground.
Make the horizon line relatively low in the paintingApex
It is the horizon.
Keep a weather eye on the horizon means to watch the horizon or as far as you can look for ships=water, people=land or water, or an animal=land or water.
Depends on how sunny it is that day
6.23 miles
the horizon
If you were on the water with an unobstructed view, you would be able to see 2.692 miles or 2.338 nautical miles.
There is no horizon in deep space.
It seems like 1,000,000,000,000,000 meters away
B Horizon
You can't reach the horizon. No matter where you are or what you do the horizon will always be there in front of you. The distance between the shore and the horizon is infinite.
It Maybe B horizon or C horizon
Our eyes can only see as far as the horizon, due to the curvature of the Earth. For instance, an observer standing on a hill 100 feet (30 m) in height, their horizon is at a distance of 12.2 miles (19.6 km). Obviously, without the restriction of a horizon, we can look out far into space on a dark night and see our moon and many stars and planets with the naked eye - even better with a telescope.
That depends on the angle of elevation