How far a naked eye can see in daylight & at night & how does it relate to the size & brightness of the object

Answer 1

Usually, a naked eye can't see the sun. u should be wear a mask. Now, at night it happens again the same thing. It can't see anything only some objects that are luminous. The eye can only compass the 3 girths from the 9 that they exist.
1.height
2.lenght
3.width

Answer 2

The higher the contrast between an object and it's background the further away it can be seen. Standing on the earth, if you are 6 feet tall, the horizon is about 7 miles away. Tall objects, of course, can be seen much farther. In clear air you can see mountains more than 200 miles distance (you would see only the tops...the horizon would be in the way of the base). The farthest object you can see with no optical aid is the Andromeda Nebula (really a galaxy like the Milky Way), and it is over 2 million light years away.

If you ever are in the New Orleans area cross the Lake Ponchartrain Causeway Bridge at night, coming from the north. It has "high rises" on it (humps) for lake traffic, and as you go up on one you can actually watch the city of New Orleans "rise up out of the water" and sink back as you go down the other side. It is quite spectacular, and one of the few places in the world that you can actually watch and see the result of the curvature of the earth. That bridge is nearly 24 miles long, and the city is close to 30 miles distant.

Answer 3

On a clear day, from old firefighter tower an person with 20/20 eye sight can see and identify various animal like man or a monkey(same size). A man or a woman. A cow or a Buffalo. A goat or a ship. Up to 7 miles away (military data).

Night vision is tricky some can see lot More then the others, I have not seen any data on it.

But in general bigger the object more visible irrespective of night or day.

Answer 4

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