How do astronauts train for the microgravity of space when they’re on Earth? One well-used method is clever, effective, and simple: they use a pool! A water environment simulates the feeling of near weightlessness, or microgravity. It makes the perfect space to engineer, build, and get comfortable moving around in space-like conditions. NASA astronauts use the Neutral Buoyancy Laboratory in Houston Texas. Bigger than an olympic sized pool, it contains over 6.2 million gallons of water!
Why does a pool simulate microgravity? It’s not that objects in water are pulled on by gravity less, because the amount of gravity is the same regardless of the medium you’re in. It’s just that water is more dense than what we’re used to being in, air. Because of this density difference, we feel another force opposing gravity. The buoyant force! We’ve all felt the buoyant force and seen buoyancy in action, even if you didn’t know what to call it. The buoyant force is the force that springs a beach ball to the surface when you shove it under water, the force that makes a helium balloon float in air, and the force that makes humans feel like they’re floating when they’re in water.
In a pool, it’s buoyancy that opposes gravity, and effectively makes gravity feel less intense when we’re in it. As long as you’re in something denser than our average density, you’ll feel the buoyant force pushing up on you, and feel lighter! That’s why people float even more on saltwater than freshwater; saltwater is more dense. Our microgravity activity challenges campers in the same way astronauts are challenged in space. Their mission is to work together and build a “satellite communication system” with pipes and other pieces while floating and communicating without words.
After debriefing the mission to hear about the hardships and victories during their underwater adventure, campers may also have time to learn, hands-on, about the interesting physics of space and pool physics (think buoyancy, density, and pressure) with instructors. This activity is adapted to the needs of the group, to ensure each camper is sufficiently challenged but poised to succeed in the pool, both school year and summer. Lifeguards are on deck to supervise and create a safe space! There are many ways to do this class, but each camper should walk away feeling a little more confident working together, engineering in a unique environment, and with the experience of training like an astronaut in the AstroCamp pool!