How far can you see on the open ocean?
In: 45
If the weather is clear and you stand at sea level, a person of average height can see about 4-5 km, or ~3 miles.
The visible distance varies greatly however as it’s very dependent on weather conditions, if the sea is calm etc. Also your height will have an impact. A longer person will see further than a short person.
It depends on your elevation above the sea. This is why ships as late as WWII had crows nests in the top of the mast as people could see further from there. And still today the radars are placed in the top of the mast for better reach. The traditional answer is 3 nautical miles which is a good estimate for how far a person standing close to the ocean can see. But if you go up a deck you can see twice as far, go up two more decks and you can see twice as far again. And if the ship you are looking for is also four decks tall you can see it twice the distance again. So suddenly the 3 mile viewing rage have increased to 24 miles.
Measure how far your eye is above the surface of the sea in feet. Take the square root of this number and multiply by 1.225. That’s the distance to the horizon in miles. This approximation becomes less accurate for the higher you go but is good enough in most circumstances.
Of course, if the object you’re looking at is also above the surface of the ocean, you can see it over the horizon. Use the same method as above with the height of the distant object and then add the two horizon distances.
Two things to consider, how high above the water you are and how high above the water what you are looking at is. Say you are standing at the water, at 5 or 6 feet above the water, the horizon is about 3 miles. So you could in theory see a person’s whole body if they were standing at the same level. As theybget further away, you see less of them, until they are at about 6 miles, and you would only see the top of each other’s heads.
As you, or what you are looking at get higher above the water, the further away you can see them (think boats, buildings, etc.)
Depends on how tall you are/how high above the water you are. Also depends on if you’re talking about distance in a straight line from your eyes vs distance on the surface of the Earth.
When you’re near the surface, it changes pretty quickly with how high you go, when you’re very far away you can see nearly half the planet(you’d need to be infinitely away to have line of sight to exactly half the planet).
h = height above earth’s surface
r = earth’s radius
d = straight line distance from your eyes to the horizon
You can make a right triangle with sides r, d, and (r+h), with r+h being the hypotenuse. Then use the Pythagorean theorem to calculate what d is.
Ends up being distance = sqrt(2* radius of earth * height + height^2)
You can see about 16,308 light-years. That is the distance to the furthest star visible with the naked eye. Perhaps your questions is about things like the curvature of the earth and particles in the atmosphere?
I thought I remembered Bill NYE saying you could a match being lit across the Bering Strait. But maybe that’s just eyesight.
https://en.m.wikipedia.org/wiki/Horizon
You can use pythagoream’s therom. The sum of the squares of the sides of a right triangle is equal to the square of the hypotonuse.
At 1 miles, the drop is .6 foot.
At 1 km, the drop is 8 cm
Assuming no atmospheric refraction and a spherical Earth with radius R=6,371 kilometres (3,959 mi):
For an observer standing on the ground with h = 1.70 metres (5 ft 7 in), the horizon is at a distance of 4.7 kilometres (2.9 mi).
For an observer standing on the ground with h = 2 metres (6 ft 7 in), the horizon is at a distance of 5 kilometres (3.1 mi).
For an observer standing on a hill or tower 30 metres (98 ft) above sea level, the horizon is at a distance of 19.6 kilometres (12.2 mi).
For an observer standing on a hill or tower 100 metres (330 ft) above sea level, the horizon is at a distance of 36 kilometres (22 mi).
For an observer standing on the roof of the Burj Khalifa, 828 metres (2,717 ft) from ground, and about 834 metres (2,736 ft) above sea level, the horizon is at a distance of 103 kilometres (64 mi).
For an observer atop Mount Everest (8,848 metres (29,029 ft) in altitude), the horizon is at a distance of 336 kilometres (209 mi).
For an observer aboard a commercial passenger plane flying at a typical altitude of 35,000 feet (11,000 m), the horizon is at a distance of 369 kilometres (229 mi).
For a U-2 pilot, whilst flying at its service ceiling 21,000 metres (69,000 ft), the horizon is at a distance of 517 kilometres (321 mi).
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