Spacey s’mores were on the menu at A Place for Girls on Aug. 10, as day campers made the traditional campfire treats using solar ovens created from pizza boxes.

Becky Jaramillo, a senior educator at the National Institute of Aerospace and a Girl Scout alumna, was invited as a guest speaker to talk about the science behind making the gooey camp delicacy in celebration of National S’mores Day.

Jaramillo came armed with baskets full of what looked like craft supplies, but in reality were the makings for experiments.

The girls made their own lenses and used filters to bend and spilt light into wavelengths, which allowed them to see the colors that make up white light. Since it was a cool and cloudy morning, the girls were able to see more ultraviolet than infrared rays through their filters, so they decided to set up their solar ovens to reflect the ultraviolet light rays onto their s’mores, rather than rely on infrared heat from the sun for cooking.

“At NASA, we are always looking at sunlight and how it travels through the atmosphere,” Jaramillo told the girls. “Being able to understand the sun and light makes it possible for us to stay safe while making new discoveries.”

The girls also made bracelets with ultraviolet color-changing beads so they have a reminder of when they are exposed to harmful rays of light and need to protect themselves from the sun. After their lesson in science, the girls had the opportunity to make and enjoy their own s’mores.

The first printed recipe for s’mores dates back to a Girl Scout handbook published in 1927 and is credited to Loretta Scott Crew, who reportedly made s’mores by a campfire for a group of Girl Scouts.

Originally, the treats were called “some mores.” It is unknown when the name was shortened to “s’mores,” but recipes using the longer name can be found in various Girl Scout publications through 1971.