Cats (and many other animals) have a layer of cells behind their retinas called the tapetum lucidum. This layer enhances night vision by reflecting light that passes through the retina back into the eyes. When light enters the eye, some of it is absorbed by the retina's cells, allowing the brain to process visual information. However, the tapetum lucidum reflects the remaining light back through the retina, giving the photoreceptor cells a second chance to detect the light. This reflection of light enhances their night vision capabilities and is what causes a cat's eyes to appear to glow in the dark or in low light conditions.

The refractive index of diamond is approximately 2.42. Diamond has a very high refractive index, which means it bends light at a significant angle when it enters the diamond, contributing to its sparkling brilliance.

The Agni missile is a family of medium to intercontinental range ballistic missiles developed by India, named after one of the five elements of nature. The first missile of the series, Agni-I was developed under the Integrated Guided Missile Development Programme and tested 1991.