Why is the sky blue?
What is lightning?
What are the states of matter?
Does hot water freeze faster than cold?
Why does a can of Coke sink while a can of Diet Coke floats?
Why do you close your eyes when you sneeze?
Why do mosquitoes bite me more than my friends?
Why do your feet stink?
How does gravity work?
How fast does the space shuttle move in orbit?
What is escape velocity?
What would happen if you turned on your headlights while moving at the speed of light?
We were surprised to find that not everybody has this reflex. Sneezing is controlled by the medulla oblongata, the section of the brain that also oversees primitive functions like heart rate and breathing. What we couldn't find out is a definitive answer to the question. We heard speculation -- but only that -- that the closure could be a defensive reaction that keeps exhaled viral particles out of your eyes.
