Have you ever wondered how is it that Cole Hamels can throw a curveball and fake out the batters? As we so often find out in science, things may not be as simple as we first thought:

Initially, there was a debate over if a curveball actually curved in the air. Some people thought it might only be an optical illusion, while others argued that it really curved. Eventually, it was shown that curveballs really do curve (Check out this page). How? It all depends on how the baseball is spinning when it leaves the pitcher’s hand. Proper curveballs spin in such a way to create an area of high-pressure on the top of the ball (or slightly off to the side) to force the ball downwards faster than it would fall with gravity alone (Thank you Wikipedia).

But wait! It turns out that those who thought curveballs were merely illusion were not totally wrong! While a curveball does actually curve, its movement is exaggerated by an optical illusion. The illusion was recently shown by Arthur Shapiro of Bucknell University in Pennsylvania (and can be seen here), whose illusion was voted the best visual illusion in the world. So what is Cole Hamels really throwing at the plate? Looks like part curving ball, part optical illusion.

By now you’re probably wondering why there is a cute picture of a group of kids wearing Phillies gear gathering around a large metal bowl and not a picture of someone throwing a baseball. Good eye! This is a picture from when Wondergy was at the Phillies to make ice cream and explore the science of states of matter (our CoolScience program). This year is our third season with the Phillies!