Collectively known as “the holidays”, this time of year brings people together to share beliefs, family traditions, religious rites, and, for many, the celebration of miracles. I honor the beliefs of all, and those who celebrate the miracles that are a key part of their faith. I also value the science all around us, everyday. Today’s blog will be about the science of candles within and surrounding the traditions and rites common to this holiday season.
Holidays I celebrate
My family is an interfaith family. We celebrate both Hanukkah (however you choose to spell it) and Christmas. One of the major symbols of Hanukkah are the candles of the menorah, or chanukiah. The menorah has space for nine candles. Eight of these represent the miracle of the oil in the destroyed temple lasting eight days. The ninth is the shamash, the attendant or helper candle used to light all of the others.
Christmas, too, has an association with candles. Candles have traditionally been used, even long before our current rites and celebrations, to provide light in the dark of December. In addition, candles placed in windows are a traditional Christmas celebration. These could represent the openness of the dwelling to provide shelter to others, or the waiting for or missing of loved ones.
Other holidays, at this time of year and others, also celebrate with candles. Kwanzaa is an annual celebration of African-American culture and features the seven candles of the kinara. These represent the seven principles of Kwanzaa.
And of course, a nod to all of those people born from mid-December to mid-January, whose birthdays and associated candles too often get subsumed by the winter holidays.
The science of candles
What is the science of candles for the holiday season? How do candles work? What is actually burning, and what happens to the wax? Before we get into the details, I will let you in or a secret. The constant flame you see is not (or at least not directly) from the burning of the wick.
I pulled the following information from the site scienceabc.com.
The two main parts of a candle are the wick, a piece of string, and the wax, the source of fuel that surrounds the wick. When the wick is lit, usually with a match, wax near the lit end of the wick begins to melt, turning from a solid to a liquid.
The wick absorbs the now liquid wax and pulls it upward. That pulling is called capillary action. If you dip the corner of a paper towel into colored water, you can see capillary action in progress. The color will travel up the paper towel.
As the fuel (the liquid wax) reaches the initial flame of the wick, it vaporizes. Vaporization is when a liquid turns into a gas. The now gaseous fuel combusts. Combustion is the burning of a substance in the presence of oxygen. The oxygen in this case is in the surrounding air, combining with the hot gaseous fuel that was once solid wax. So long as there is still wax around the wick, the flame, due to this combustion, continues.
So what happens to the gaseous fuel? It combines with oxygen to form carbon dioxide gas, which is odorless and colorless. You will likely still see some smoke, though, because of contaminants or other substances, such as they dye used to color it, in the candle. These may not burn cleanly to produce carbon dioxide, and therefore produce smoke.
A holiday season
May you and your loved ones enjoy the holiday season, and the light it brings.
