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Springing forward: Understanding Daylight Saving Time

image of a clock

As clocks spring forward this weekend, moving from Standard Time to Daylight Saving Time (DST), the debate still continues as to how efficient DST really is.

Many people believe keeping time dates back as early as 1,500 B.C. from ancient Egyptian and Babylonian astronomy; although some think it dates back even farther.

“Historically, the sun kept the time,” explained Tom Willmitch, the director of Illinois State University’s planetarium. “Time keeping has deep ties to astronomy and the sky is essentially a big clock.”

The early methods of time keeping involved the use of a sundial, which is what Standard Time is based upon today. The sundial is placed in a certain position and the sun casts shadows on the dial, which indicates the time of day. “When the sun is due south, that indicates noon on the sundial for Standard Time,” said Willmitch. “When time switches to Daylight Saving Time during the summer months, the sundial shows one o’clock when the sun is due south.”

The history of Daylight Saving Time is quite complex.

“It’s considered a relatively modern idea. Wide adoption began in the early 1970s in response to the energy crisis,” said Willmitch, who noted Congress passed a bill believing the time change would save energy.

As recently as 2007, the start and end dates of Daylight Saving Time was changed to begin three weeks earlier and end one week later than its original inception. Although there are several reasons for the push for these changes, Willmitch said the candy and retail industries have had a huge impact. “Both industries heavily lobbied Congress. The candy companies wanted more daylight on Halloween to increase sales,” he said. “Therefore, Congress pushed the end of Daylight Saving Time back one more week in the fall to end after Halloween.”

Willmitch also explained how the retail industry has benefited from DST. “Research shows that people shop more during daylight hours, and longer hours of daylight after work means more revenue for merchants,” he said.

Despite the positives, Willmitch also added that he isn’t a big fan of Daylight Saving Time, “It just seems wonky. It seems very unnatural.” He said he isn’t the only one against DST. “The farmers have not been in favor because the best time to plant seeds is after the dew evaporates. This means farmers have to begin planting an hour earlier.” Entertainers don’t typically like DST either. “They like to perform in the dark. This time change in the summer means they have to perform much later into the evenings.”

There are many other reasons that have been proposed throughout the years against DST. “It isn’t good for our health. Statistics show there is an increase in heart attacks during the first week of Daylight Saving Time,” he said. “There have also been some studies conducted by utility companies that show a rise in electricity consumption instead of a decline, as Congress suggested would happen.”

Willmitch believes the Daylight Saving Time debate will continue. Nevertheless, time will march on.