Calculate the diffraction limit of the human eye, assuming a wide-open pupil so that your eye acts like a lens with diameter 0.8 centimeter, for visible light of 500-nanometer wavelength.

How does this compare to the diffraction limit of a 10-meter telescope?

he Dawes limit says that the resolving power is 11.6 / d, where d is your eye's pupil's diameter in centimeters. You're eye's pupil can dialate to about 7 mm, or 0.7 cm. So 11.6 /.7 = 16.5 arc seconds, or about a quarter arc minute. However, the standard answer for what people can really see is about 1 arc minute. It's linear, so 10000 / 7 = 1428 times better for the 10 meter scope. However, unless the scope is in space, the atmosphere will take a big chunk from that.