Can you see a person two miles away?

Question

My girlfriend and me have a bet going. I say you can see a person that is two miles away, and she says there's no way. Also, you have to be able to tell that it is a person. We are going to go out and test this, but first we wanted to see what you guys think. So,can you see a person that is two miles away?

Answer 1

yes. it depends on alot of things though. humidity is the major one, heat waves will distort the veiw also. in space, the best condition, it would be very easy

Answer 2

It depends on the terrain, and in some cases, the climate (eg. if it was very hot your vision could be blurred).

Answer 3

You use the Rayleigh criterion for a circular aperture.

r=1.22(lamda)/nsin(theta)

r  is the aperture radius , your eyes

are 8cm apart

n is refractive index=1

lambda is the wavelength of light,

just take it as 500nm (note the nano)

theta depends on the width of the

thing you're tring to see (baseline 1m)

and the distance away (straight line 3000m)

cant draw the triangle here but you can yourself

anyway theta is 0.001 degrees

so yeah, sub em in and yeah,you can resolve

someone two miles away. Thats what she gets for not knowing her optics. pwned.

Answer 4

Assuming perfect atmospheric conditions...

A 5 foot tall person at 2 miles (10,560 ft) would appear:

tan^-1 (5/10,560)

= 0.027 degrees, or

0.027 * 60

= 1.62 arc minutes tall

This site - http://www.michaelbach.de/ot/lum_hyperac...

claims normal human visual resolution to be about 1 arc minute, so a human at that distance would be 62% larger than the minimum that you can see.

This doesn't necessarily mean that you could tell it was a person, but you would be able to tell it's not just a spot.

Keep in mind if you test this on flat ground the curvature of the earth is going to come into play.  You need one of the people to be on top of a house or something.

You've got a chance :)

Answer 5

With Noc's....

Otherwise, I don't think so. AND tell its an individual person? Not just a person...