In March 2019 Twitter user Unusual Facts shared a pair of photos that had people asking whether they had an undiagnosed eye condition. And the pictures went viral, spreading across the internet until it seemed like the whole world was asking whether it had a problem with its vision.
We’ll talk about the vision issue – and Unusual Facts’ photos – later, but first of all, let’s look at the eye. This vital organ resembles a globe shape, and it’s not much more than an inch across. Although some believe that it’s the same size in adults as it is in babies, this isn’t right. In fact, it actually grows about 50 percent from birth to adulthood.
Eyes work by having the lens, at the front of the eye, project beams of light onto the back of the eye. This process is called “focus,” and focused light falls on cells that can sense it, which together form the retina. These change the light into bursts of electricity, which the optic nerve then conveys to the brain, where they are interpreted.