Did you know that the human eye is so sensitive that could spot a candle flame flickering up to 30 miles (48 km) away, assuming the Earth was completely flat and dark? [Read more…] about The human eye could see a candle flame flickering up to 30 miles
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When does the pupil of our eye expand?
The pupil is a hole located in the center of the iris of the eye that allows light to enter the retina. But do you know under what conditions does it expand? [Read more…] about When does the pupil of our eye expand?