Sometimes,observers see this as a comet's tail, which can be visible to the unaided eye stretching across the night sky.

VOA: special.2011.02.09

Then while the writhing pitcher ground the ball into his hip, Defiance gleamed in Casey's eye, a sneer curled Casey's lip.

VOA: special.2011.04.04

No one but her lover saw it. Every eye but his was fixed on the man in the arena.

VOA: special.2009.04.18

Degas and the Impressionists were interested in painting the effects of light, and how the human eye sees subjects.

VOA: special.2009.07.12

And so that can result in the front part of the eye drying and not staying moist and protected like normal."

VOA: special.2011.08.01

For thousands of years, the eye of Horus remained as a sign of the god's help to the suffering and sick.

VOA: special.2009.03.22

Some people are found to have cataracts, abnormal growths on the eye that can lead to loss of eyesight.

VOA: special.2009.03.30

Some eye care professionals say all that screen time has led to an increase in what they call computer vision syndrome.

VOA: special.2011.08.01

They call it Netra, which means eye in Sanskrit but stands for Near Eye Tool for Refractive Assessment.

VOA: special.2011.05.16

Yes,it was this! He had the eye of a bird, a vulture -- a pale blue eye, with a film over it.

VOA: special.2009.05.16

When each eye sees very similar, but different versions of an image, the brain thinks it is seeing depth, or three dimensions.

VOA: special.2010.01.26

She also shows how the chemical Luminol can reveal hidden blood stains that the eye alone cannot see.

VOA: special.2010.05.05

"No!" he answered. His eye glasses became wet and he had to look over top of them to see the other man.

VOA: special.2010.03.20

The ancient Egyptians used a drawing of the eye of Horus as a magic sign to protect themselves from disease,suffering and evil.

VOA: special.2009.03.22