Dear Zamaria,

When astronauts leave Earth, a spacesuit can help them stay safe in places that are quite different from their home planet.

I learned all about it from my friends Stasia Kulsa, Lauren Reising and Ian Wells, a few members of a team at Washington State University researching how to clean moon dust from spacesuits.

On Earth, dust can sometimes be annoying, but dust from the moon can cause lots of problems for astronauts. The team is working on a “spacesuit car wash” that will keep astronauts healthy and their equipment clean. They told me that spacesuits help astronauts stay safe in lots of different ways.

Let’s say you were an astronaut heading to the moon. Here on Earth, we breathe oxygen all day, but on the moon there isn’t nearly enough oxygen to breathe. Astronauts may carry oxygen tanks on the back of their suits or use a hose that connects their spacesuits to a space station and delivers oxygen they can breathe.

On the moon, it can also reach about 260 degrees Fahrenheit during the day and -200 degrees Fahrenheit at night. The human body can’t handle those temperatures, so spacesuits are designed with materials that allow astronauts to survive in extreme conditions.

Some of these materials are called insulators, and they work similarly to a sleeping bag. When the astronaut’s body temperature rises, the material absorbs the heat. But when the temperature drops, the material gives off heat. The spacesuit can help astronauts maintain a healthy body temperature.

Another reason astronauts need spacesuits has to do with changes in air pressure. As we go about our day, air is always pressing down on us. We don’t get crushed by this pressure because just as air pushes down on us outside of our body, it’s also pushing from the inside out. These two opposing forces help keep things in balance, or equilibrium.

If you left Earth’s atmosphere and headed to a place like the moon where there was less air pressure around you, that equilibrium would get out of balance. The body would likely start swelling as it tried to find balance again. A spacesuit also helps provide just the right amount of air pressure. It’s not quite as much air pressure as there is on Earth, but it’s enough to keep the astronauts safe.

There are many details that go into an astronaut’s complex spacesuit, but those are just a few. It turns out astronauts even wear a Maximum Absorption Garment which allows them to go to the bathroom in space. They also have helmets that contain a little block of foam they can use to scratch their noses. People who design spacesuits think of everything, don’t they?

Of course, spacesuits have changed quite a bit over the years. Creative people—like my friends at WSU— are always coming up with ways to help improve spacesuits. Who knows, maybe one day you can help design spacesuits or become an astronaut who wears one on a mission.

Sincerely,
Dr. Universe

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