In 2019, Nickelodeon's green slime, the gooey substance made famous by the network's children's shows and its long-running tradition of dousing celebrities, traveled to the International Space Station as part of a genuine scientific experiment. The television network teamed up with NASA to send the sticky material into orbit and study how liquids behave in microgravity.
The project, called Slime in Space, used the station's weightless environment to observe what happens when a highly viscous material is freed from the effects of gravity. The slime was a non-Newtonian fluid, meaning its viscosity changes depending on the force applied to it. According to information from the experiment, its consistency was roughly 20,000 times greater than that of water, which made it move very differently from an ordinary liquid once in orbit.
How the experiment worked aboard the station
The slime reached the space station aboard SpaceX's 18th commercial resupply mission. Once inside the orbiting laboratory, astronauts Christina Koch, Drew Morgan and Luca Parmitano ran a series of tests with the substance and with water for comparison. To handle the materials, they used tools including ping-pong paddles coated with a superhydrophobic finish designed to repel water.
The program included at least eight separate demonstrations. The astronauts spun the substances, tried cutting the slime with dental floss, created bubbles using syringes, and examined how the material responded to stretching and movement. One of the most striking moments came when a jet of slime shot from a syringe passed through a bubble in front of Parmitano, who became the first person to be hit by slime in space. In another test, two paddles coated in the substance formed a long liquid bridge that eventually broke apart into five separate drops.
What the slime revealed in microgravity
Behind the playful setup was a serious research goal. Mark Weislogel, a professor of mechanical engineering at Portland State University, and his research assistant, Rihana Mungin, helped design and analyze the demonstrations. Their aim was to gather data on properties such as density, surface tension and viscosity in conditions where gravity no longer dominates how a liquid behaves.
The breakup of the slime bridge was of particular interest to Mungin. She said she had previously observed a similar phenomenon under a microscope, but at a scale roughly 1,000 times smaller and over a time interval more than 1,000 times shorter. The station tests made it possible to see fluid dynamics that on Earth are normally obscured by the weight of the substances involved.
Possible uses for liquid handling and space farming
The project's value went beyond simply watching a sticky substance float around. In space, many systems built to handle liquids work differently because they were designed around gravity, creating challenges for technologies that manage, contain or move fluids.
NASA said the knowledge gained from the experiment could contribute to technologies for creating, shrinking and containing droplets in low-gravity conditions. It could also prove useful for hydroponic growing systems, where delivering water to plants is expected to be an important task on future space missions.
The project also had an educational component. The space agency produced a 15-minute virtual field trip aimed at students in third through fifth grade. According to the public viewing figures cited in the experiment's information, the material has drawn more than 600,000 views, turning a slime experiment into an accessible way to explain concepts in space physics.
