How STEM Shows Up in Every Part of Christmas 🎄

The holiday season is here. The air smells like cinnamon, cookies are baking, and houses are glowing with strings of lights. Most associate it to magic, but if you really think about it, it's all to do with STEM. All thanks to science, technology, engineering, and math, we are able to enjoy and make the most of the holidays!

From the physics of lights to the chemistry of candy canes, here is how your living room becomes a small lab every December. Take a look!

Christmas Lights: Physics in Action

In every tiny bulb on a string of lights, electricity flows through the filament, which heats it until it glows. This process is called incandescence. Most traditional strings of lights use series circuits, which means if one bulb is damaged or removed, the current cannot flow through the rest of the string (so none of the lights work).

The way the lights are arranged also use concepts of geometry. Wrapping a tree in spirals or patterns uses of spatial math. Untangling a string of lights utilizes entropy, the natural tendency of systems to move from order to disorder. Who would've guessed something as simple as lights involves basic principles of physics?!

Candy Canes: Chemistry You Can Taste

Candy canes are more than a holiday treat.

Have you ever taken a mint and felt that tingling feeling when you breathe in the cold air? Well, that's due to the peppermint flavor, which comes from menthol. It triggers a cooling sensation on the tongue.

The crunch of a candy cane comes from sugar crystallization! How it works: heating sugar to a precise temperature and then cooling it quickly creates a brittle, glass-like structure.

The Christmas Tree: Engineering at Work

The triangle shape of a Christmas tree gives it a low center of gravity, which allows the tree to hold ornaments without tipping over. In nature, conical shapes help snow to simply slide off the branches so they do not break.

Ornaments also embed elements of engineering. Glass ornaments are molded to maintain shape, artificial ornaments are designed to resist damage and artificial snow reflects light to create a winter effect.

Santa’s Sleigh: A Physics Challenge

If Santa’s sleigh were real, delivering all the presents in one night would be impossible without incredible speeds and huge distances. Scientists have tried calculating how fast and far he would need to go, based on time zones, Earth’s size and the number of homes that celebrate Christmas.

Because of time zones, Santa can chase midnight around the world. This gives him about 31 hours to deliver gifts instead of just 24 (Cho, 2025).

Even with extra time, the sleigh would need to travel at mind-blowing speeds. One estimate says 10 million km/hour, which is 2,800 kilometers per second: more than 200,000 times faster than the fastest human runner (Phys.org, 2016).

At these speeds, physics gets a bit insane. Light could look different because of the Doppler effect, and sounds like bells and footsteps might be almost silent (Phys.org, 2016).

Another calculation suggests Santa would need to travel around 5.4 million kilometers per hour, which is 4,700 times faster than a commercial jet (Mission Astro, n.d.).

Even though no sleigh or reindeer could actually do this, and this is purely hypothetical, thinking about it shows how physics, math + astronomy explain what seems impossible. Imagining the laws of motion in action makes Santa’s journey even more fascinating!

Baking and Wrapping Paper: Everyday Science

Baking is all about chemistry. Heating butter and sugar triggers the Maillard Reaction, which gives cookies their golden-brown color and distinct aroma. Yeast or baking soda acts as a leavening agent, which produces gas bubbles that make dough rise.

Wrapping paper patterns use symmetry and curled ribbons demonstrate elasticity. Even small traditions like stacking gifts require an understanding of balance and structure, so they don't tip over! Science really is present in every detail of holiday preparation!!!

Why STEM Makes Christmas Cooler

Science does not take away from the holidays, but instead, it makes traditions more impressive. From lights and candy canes to trees, sleighs, and baked treats, STEM is omnipresent (and no, you can't escape science even during winter break or your time off of school, but it is undeniably more fun learning about it way!). Recognizing the science behind these activities adds a whole new level of appreciation and shows that the holidays are not only magical but also cool from a scientific perspective.

Happy holidays and may your lights stay untangled this year. Wishing you a Merry Christmas from STEMiscope!⠀⠀

References:

Cho, E.-J. (2025). The mystery of Santa Claus. Tom Rocks Maths. https://tomrocksmaths.com/wp-content/uploads/2025/06/e-jay-cho-maths-essay-the-mystery-of-santa-claus-eca1b0ec9d80ec9eac.pdf

Phys.org. (2016, December 14). Mystery of how Santa fits down chimneys, can deliver presents without being seen ‘solved’ by relativity theory. https://phys.org/news/2016-12-mystery-father-christmas-chimneys-relativity.html

Mission Astro. (n.d.). Santa’s speed: How physics explains his Christmas Eve journey. https://missionastro.org/santas-speed-how-physics-explains-his-christmas-eve-journey/⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀