Here are some rare and interesting facts about light:
1. Light is both wave and particle (photons).
2. Speed of light (299,792 km/s) is the universe's speed limit.
3. Human eyes can detect 1-100 billion colors.
4. Light can travel through 30 cm of water or 1 km of fiber optic cable.
5. Lasers can produce 100 billion times more intense light than the sun.
6. Light therapy treats Seasonal Affective Disorder (SAD).
7. The universe's oldest light is from the Cosmic Microwave Background Radiation (13.8 billion years old).