An experiment designed by two eighth-graders from a North Charleston charter school soon will be out of this world. Literally.

Griffin Eslinger and Alexander Puckhaber, who attend Palmetto Scholars Academy, created an experiment that is headed for outer space as part of the national Student Spaceflight Experiments Program. That program is run by a nonprofit in cooperation with a for-profit company.

Theirs is the only South Carolina school experiment that will be aboard the Orb-1 Cygnus Rocket as it journeys to the International Space Station, and at least one of the pair plans to be in Virginia this month to watch the rocket launch.

“It’s just really cool,” Eslinger said.

“The whole process has transformed the entire school,” said Kellye Voigt, the school’s science and research teacher who spearheaded its spaceflight program.

Voigt said she thought this program would be a good fit for the sixth- through 11th-grade school (it will have a 12th grade next year) that caters to gifted and talented students. It’s important to meet their intellectual needs, she said.

She saw this as a way to engage her students in STEM (science, technology, engineering and math), and a chance to expose them to what its seniors will do, a capstone research project.

“Part of my goal was to give them a research experience that would be unforgettable,” she said.

She wrote and received a local grant that covered the $21,000 cost to participate in the program.

Students from 11 schools nationwide are sending experiments on this flight into space. One Colorado school is investigating the effect of a lack of gravity on making beer, while a Michigan school is studying calcium absorption in bones.

Eslinger and Puckhaber are hoping to find out the effect of microgravity on the oxidation of metal exposed to a salt water solution. Simply put, they want to know whether a lack of gravity changes the way iron rusts.

They have invested months in this project. During the 2012-13 school year, Voigt held hour-long after-school sessions twice a week and three-hour sessions on Sundays for six weeks for students to develop proposals with the help of community mentors. Eslinger and Puckhaber were “regulars,” she said.

The school-wide competition generated 78 proposals, and those were submitted to an expert panel at SPAWAR for judging.

“We thought there was a slim chance of being picked,” said Puckhaber, who at that time was a seventh-grader competing against high schoolers.

The SPAWAR judges whittled down the field to three finalists, and those were sent to the National Center for Earth and Space Science Education, which runs the spaceflight program. It picked the winning experiments that will go into space.

Eslinger and Puckhaber are friends and had worked together on the school’s award-winning robotics team, so they decided to collaborate on this project. They had a number of ideas and eventually honed in on this one.

“It sounds like a pretty simple thing, but writing a proposal is hard,” Eslinger said.

They’ve put a small, tensile bar in one end of a tube and salt water in the other end. A clamp separating each side will be removed once the tube reaches space, and Eslinger and Puckhaber will do the same with their controls back on Earth.

When the tubes return in March, the pair will use microscopes and a specialized machine from the College of Charleston to determine whether the rust affected the bars in different ways.

Their hypothesis is that the tensile bar will rust more in space because of the lack of gravity and the way the salt water will cover the bar.

Eslinger is the son of Dave and Sandy Eslinger of Summerville, and Puckhaber is the son of Edmond and Kasia Puckhaber of Daniel Island.

Reach Diette Courrégé Casey at @Diette on Twitter or (843) 937-5546.