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The Science Behind the Summer Solstice

The Science Behind the Summer Solstice

As the longest day of the year, the traditions surrounding the Summer Solstice are almost as ancient as the humans they originated with. Known as the First Day of Summer, Midsummer or St. John’s Day, the Summer Solstice is one of the most scientifically intriguing and culturally important days in the calendar year!

Ancient Traditions

According to the Farmers Almanac, in Ancient Egypt, the solstice coincided with the rising of the Nile River — as it was crucial for the civilization’s survival to predict this annual flooding, the Egyptian New Year began with this important day. In early Irish cultures, townspeople would cut hazel branches on the Solstice eve to be used during hunts for gold, water and precious jewels.

Across different Scandinavian cultures, Midsummer celebrations and festivals hold huge importance because of the Summer Solstice’s vast difference from its snowy counterpart (a Norwegian Winter Solstice is marked as the shortest day of the year, with limited sunlight all day long!)

The Science

(Photo by: The Bureau of Land Management)

In the Arctic Circle, in the days surrounding the Summer Solstice, the sun can be seen during all 24 hours of the day — hence the name “The Longest Day of the Year”. The day itself isn’t actually longer, it just seems that way because the Earth’s northern hemisphere is receiving the most hours of sunlight it will get for the entire year!

But, why?

Well, while early humans thought the Summer Solstice was a mystical day marked by magic and rituals, today, we know that this special day is a byproduct of the Earth’s 23-degree axis tilt. Instead of spinning vertically, the Earth is tilted 23-degrees to its side, which means that the sunlight hitting our planet’s surface is not equal throughout the year — the amount of sunlight that reaches the Earth changes throughout the year as the planet orbits the Sun.   

(Photo by: Przemyslaw "Blueshade" Idzkiewicz)

"Our Summer Solstice in the northern hemisphere is the point in the Earth's orbit when the North Pole is most inclined towards the Sun," says Manchester University's Dr. Tim O'Brien, Associate Director at Jodrell Bank Observatory.

"Over the year, the North Pole can be tipped towards the sun — summer in the northern hemisphere — or away from it, which is winter.”

“On the Summer Solstice, the sun rises at its farthest point around the eastern horizon," adds Dr. O'Brien. "At noon the sun is as high above the horizon as it will ever get, and it sets at its farthest point around the west, so daylight lasts longer than on any other day in the year." (Hastie.)

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Looking to bring the science of the Summer Solstice to your classroom? Check out or Enrichment Camp, Unleash Your Wild Side! As globetrotting artists, this STEAM camp gets students up and excited about exploring the diversity of the planet through art! 

 

 

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References
Farmer's Almanac. (2018, June 18). Summer Solstice 2018: Facts and Folklore - Farmers' Almanac . Retrieved June 20, 2018, from https://www.farmersalmanac.com/the-summer-solstice-facts-and-folklore-2958
Hastie, P. (2013, June 20). The science of the summer solstice. Retrieved June 20, 2018, from http://www.bbc.co.uk/science/0/22956681