Why Do Santa’s Eyes Twinkle?

Whenever you see Santa Claus, he always seems to have a twinkle in his eye. You might notice that in people as well; Paula did and asked me to find out how that happens. Whether you’re Christian, Jewish, Muslim, Hindu, or anything else, if you live in the U.S., you’ve probably heard lots of Christmas lore, so let’s find out why Santa’s eyes twinkle.

There appears to be two reasons. First, it conveys some form of emotion. The eyes release tears that are spread over the eyeball, just enough to make them seem slightly misted. As the light hits someone’s eyes, they appear to twinkle or sparkle.

The second reason also has to do with light. The effect seems to be greater when someone’s eyes are dilated, as from walking from a dark room into the light. Combined with the emotional misting, it really makes someone’s eyes twinkle.

Understanding why it happens doesn’t make it less meaningful—those twinkling eyes are really glad to see you, just like Santa who seems glad to see everyone. We’ll explore the science behind Santa’s dimples on Thursday.

Happy Hanukkah, a belated Happy Mawlid al-Nabi, happy Dhanu Sankranti, Merry Christmas, and Happy Holidays to everyone!

What are you prepared to do today?

Dr. Chet