by Bob McDonald
It takes a little time to get used to floating all the time. First-time fliers tend to bump into other people and bounce off walls because they push too hard and have trouble controlling themselves. But they soon learn to do everything in slow motion and move using mostly their fingertips. No one wears shoes because no one walks. Everyone flies!
One way to experience weightlessness on Earth is in a swimming pool. If you are really good at holding your breath, you can go to the deep end of a pool. Take a deep, deep breath, then slowly let the air out of your lungs until your body begins to sink. Hold your breath at that point and try to suspend yourself in the middle of the water so you are halfway between the bottom and the surface.
When you’re floating still like that, neither sinking nor rising, you’re what is called neutrally buoyant. You’re experiencing what it is like to have nothing touching you anywhere on your body. That is what weightlessness feels like. It’s like leaping off a diving board, then, just before you hit the water, the pool disappears and you just keep on falling and falling. It sounds scary, but for astronauts, it is a lot of fun.
At the end of the day, astronauts still have to go to sleep, just like the rest of us. But how can you lie on a bed if you don’t weigh anything?
Simple. You hang yourself on the wall.
Sleeping quarters on the space station are about the size of a small closet. There is a laptop mounted on one wall so you can check messages from Earth, a small window to look out, and a sleeping bag attached to the opposite wall. You crawl into the bag and then you can either tuck your arms inside or stick them through holes in the side of the bag and let them float free in front of you. Some astronauts have slept floating in the middle of the space with their legs crossed and arms folded. Whatever the position, everyone finds sleeping in space extremely comfortable because there is no pressure on any part of their body from the bed, pillow, or covers.
Astronauts make spaceflight look easy, but some say that after returning to Earth, getting used to gravity again is just as confusing as going up in the first place. After living in a world where your body weighs nothing, the return of gravity feels cruel. Everything is heavy, your head feels like a bowling ball on top of your neck, and your arms feel like logs. One cosmonaut who spent more than a year in space said that even his eyelids felt heavy when he opened them. Some astronauts have trouble balancing when they get back—the organs in the body that tell us where up and down are get turned off in space, which makes it tricky to walk on Earth when you get back, especially when you’re going around corners.
If all of this training to become an astronaut is not for you, there are thousands of other jobs that keep those astronauts up in space: engineers who build the spaceships and launchpads; technicians who work on space suits; doctors who monitor the health of astronauts; scientists who design experiments for space; and robotics people who work on the Canadarm and other systems.
While you’re waiting to become an astronaut, try spotting their spacecraft from down here on the ground. The space station is so big it can be easily identified in the night sky. It looks like a very bright star or an airplane moving smoothly across the sky, except it doesn’t have any blinking lights on it. You can see it from every major city in North America. You just have to know when it’s passing over your city and where to look in the sky. There are a number of web pages that will tell you when the International Space Station is passing over your city or town. As you watch the station fly overhead, think about the fact that there are people living inside it. If you dream hard and work hard, perhaps one day you will be one of them.
YOU TRY IT! Spin Cycle
Want to know what your first couple of days in space will feel like? Try this.
WHAT YOU NEED
Lots of floor space, or a wide space outside
WHAT TO DO
Bend over and tilt your head down as far as possible so you’re looking straight down at the ground.
While holding your head in this position, spin yourself around as fast as possible at least five times (or more, if you can).
After the last spin, stand up and try to walk in a straight line. You’ll probably find yourself staggering to one side.
What just happened? Any time you move your head, the fluid in your ear canals sloshes around, sending signals to your brain that your head is moving. When you stand up after twirling around, the fluids keep spinning for a few seconds, signaling to your brain that your head is tilting to the side when it’s really not—your brain thinks you’re falling over and tries to compensate, so you stagger until your brain receives the new message that you’re balanced.
In space, the false signals to the brain make astronauts lose their sense of up and down. Thankfully, that feeling goes away as the brain learns to ignore the false signals from the body and relies just on the eyes to figure out what the body is doing.
17 Who Was First in Space?
When you think about traveling in space, you might picture the American space shuttles or maybe the giant Apollo rockets that went to the moon. But Russia is also a space-faring country. In fact, it was the first to get there.
More than one hundred years ago, Konstantin Tsiolkovsky, a Russian scientist and schoolteacher, came up with the idea of a rocket-powered spaceship that could carry people into space. His idea of how a rocket works is the founding principle of rocketry still used today.
Russian rockets have flown into space more often than any others and are still the most reliable way to reach space. Since the Americans retired their space shuttle fleet in 2011, they have been hitching rides on Russian rockets to get astronauts and supplies up to the International Space Station. The two countries help each other and work together. But it hasn’t always been that way…
The beginning of the Space Age was actually a space race, and it was all about rockets. The United States and Russia, then called the Soviet Union, were both in a race to build a rocket big enough to get into space.
Both countries built bigger and bigger rockets, trying to beat each other and prove who was more powerful by becoming the first country to successfully send a man-made object into orbit. Eventually, in 1957, the Russians won the race when they launched a small, shiny, spherical satellite about the size of a basketball. Sputnik became the first object other than the moon to orbit the Earth. It was our first artificial satellite and it marked the beginning of the Space Age.
Sputnik wasn’t very big, but it did prove that the Russians had rockets powerful enough to reach space. On their third launch, they sent another probe, not much larger than Sputnik, past the moon. Then, to prove their rockets were even more powerful, they sent up a dog named Laika—the first living creature to fly in space. Unfortunately, she also became the first animal to die in space because the Russians didn’t have a way to bring her capsule home. She was followed by two other dogs—Belka and Strelka—who did make it back to Earth and can now be seen stuffed in a museum in Moscow.
But there was still one more big, important step that the Russians and Americans wanted to take… and they each desperately wanted to be the first to take it. They wanted to put a human being into space.
In 1961, a young Russian pilot named Yuri Gagarin climbed to the top of a Vostok rocket and blasted into orbit. He was the first spaceman. The Russians called him a cosmonaut. He was an instant hero. The name Yuri Gagarin is now in history books around the world. Following Gagarin’s flight, Valentina Tereshkova became the first woman in space—another Russian first.
The rockets that sent Gagarin and Tereshkova into space might look simple compared to a space shuttle, but the amazing thing is that the Russians still use a similar design to fly people into space today. Sure, the rockets are bigger, but Russian rockets have not changed much since the early days because Russians believe that if you get it right the first time, you don’t mess with it.
Today’s Soyuz rockets have the same shape as their predecessors, and they still use small capsules—only now they carry three
people instead of one. It is very cramped inside, with the three cosmonauts jammed in shoulder to shoulder. Fortunately, they don’t have to spend very long inside because the Soyuz is used only as a taxi to get up to the space station and back down again.
SPACE PLACES
If you want to fly in space “Russian style,” it all starts at Star City outside Moscow. Star City is also known as the Yuri A. Gagarin Research and Test Cosmonaut Training Center. All Russian cosmonauts, including Gagarin himself, trained here. That’s where they learned to fly the Soyuz capsule, which carries cosmonauts and astronauts into space and back.
A second place is the “Cosmos” Pavilion in Moscow. This huge building contains life-size models of Russian spacecraft past, present, and future. You can step inside the Russian section of the International Space Station and see their version of a space shuttle, called Buran, which flew in space only once.
Landing in a Soyuz is still somewhat primitive. The capsule has no wings, so on reentry, it falls through the atmosphere like a meteor and then opens a parachute. Just before the capsule hits the ground, retro-rockets fire, slowing it before it thumps and lands. There isn’t much control, so if the round capsule happens to land on a hill, it rolls.
The one part of the space race that the Russians lost was the race to land a man on the moon. They did build a giant rocket called the N1 that was designed to carry two men to the moon. But unfortunately, it exploded during the four times it was launched, and the program was canceled. So American astronauts were the first to plant a flag on another world. But that didn’t mean the Russians were out of the space business.
While American astronauts were collecting rocks on one part of the moon, Russian robots were roaming on another. One of them, called Lunokhod, was the first remote-controlled car to be driven on another world. It was about the size of a bathtub.
Russian robots continued to make other firsts in space by visiting other planets. Their Venera robots are the only probes to have landed on Venus. Instead of sending people to the moon, the Russians became experts at building space stations in orbit around the Earth. They’ve built lots of them—seven successful altogether. The last and largest was called Mir.
In space, where everything is weightless and floats, the modules of the Mir space station were assembled like the branches of a tree, sticking out in many different directions and joined by hatches. It got very weird when you went from one room to another. When you floated through a door or hatch in the Mir space station, you had to change your idea of where up and down was, roll your body into that position, and go into the next room. Imagine going through a door to find that the floor and ceiling are in completely different positions from what you’d expect.
Russian cosmonauts who lived on Mir for extended periods got used to this, but astronauts from the space shuttle who came up to visit Mir for only a few days at a time found it very confusing. They had to tape red arrows on the walls inside Mir pointing the way back to the shuttle because they were getting lost in this maze. The new International Space Station has solved that problem by making sure all the modules have up and down in the same direction.
The Russians did make one attempt to build a space shuttle. They called it Buran, which means “snowstorm” in Russian. It’s no coincidence that it looked similar to the American shuttle, because the Russians copied the American design, which had already been proven to work in space.
Buran flew in space only once, on a short test flight with no people on board. That one flight was just to prove that the Russian shuttles could fly, but since then, no others have left the ground.
Today, Russians and Americans work together in space, along with other countries, such as Canada, Japan, England, France, Germany, and Italy, who all got together to build the International Space Station. And there are two control centers for the Space Station—one in Houston, Texas, and one in Moscow, Russia. Both English and Russian are spoken in space.
In the future, if humans travel to Mars, it will likely be done through a similar international effort involving many countries because the cost of going to Mars is so astronomically high. No single country would want to pay so much to visit another planet. So, instead of the competitive space race that led us to the moon, a Mars trip will be accomplished through cooperation—we’ll all get there at the same time, rather than trying to be there first and doing it alone.
YOU TRY IT! Floating Freely
Spaceflight is actually falling all the way around the Earth without hitting it. That’s all that weightlessness is—just falling without ever hitting the ground. On Earth, we can only experience this for a few seconds before we hit the ground, but here is a way you can show how all objects fall at the same speed, and why objects in space float in front of your face.
WHAT YOU NEED
A swimming pool with diving board
A ball
WHAT TO DO
Stand at the end of the diving board and hold the ball straight out in front of you.
Jump off the diving board as high as you can.
Let go of the ball while you are in the air (don’t throw it).
You and the ball should hit the water at the same time.
You have just experienced weightlessness like an astronaut!
When anything is falling, it’s weightless. Both you and the ball are weightless when you are in the air. And the neat thing about falling is that gravity makes all objects fall at the same speed.
When you see astronauts floating around inside their spaceship, it looks like there is no gravity in space. Actually, there is lots of gravity up there, almost as much as there is down here on the ground. The reason the astronauts are floating is because they’re falling all the time.
So just like you and the ball hitting the water together, astronauts, their spaceships, and everything inside them is falling together around the Earth, which is why everything is weightless and why everything you do in space—moving from one side of a room to another, eating dinner, brushing your teeth—happens while floating freely.
18 What Happens to Your Body in Space?
Space is a lazy place. Your body floats all the time, so you don’t have to walk. And anything you pick up floats along with you, so your muscles don’t get much of a workout. It sounds wonderful to be able to fly everywhere you want to go, but that lazy environment causes your body to change in many different ways that are not healthy. And if you stay in space for too long, you may not be able to walk when you return to Earth.
When astronauts first arrive in space, they sometimes don’t recognize themselves. The fluids inside their bodies that would normally be pulled down by gravity float up into their chests, necks, and faces. Astronauts find that their chests expand a bit and their legs become skinny—“bird legs,” as they say. It also produces an effect called “puffy face.” The face becomes rounder and puffy. The astronaut’s eyes start to look squinty because of the swelling.
On Earth, gravity is always pulling the blood in our bodies down toward our feet. If it weren’t for the pumping action of our hearts, we would all have really fat legs and big feet from all the blood flowing down there. We’d also be unconscious because our brains need blood to think. Thankfully, our heart is always working to pump blood upward, against gravity, so that it’s circulated throughout the body to reach all the other parts, including our heads.
In space, that force of gravity is not present, so the blood is no longer pulled down toward the feet. The heart keeps pumping blood up toward head, but it remains there because there’s no force to pull it back down. All that extra fluid in the head makes astronauts feel stuffy in the nose, like they have a cold. To counteract that effect, some astronauts take cold medicine while in space.
Another effect of the puffy face and chest is that the body thinks it has too much blood, so it starts to get rid of red blood cells. That’s not a good thing because we need all of our blood to carry oxygen and other good stuff around the body. Our bones are affected in space as
well. Our bones grow stronger the more we use them, and we use them all the time on Earth. Just standing up puts weight on your bones, allowing them to build strength as they hold you up. The more you walk, run, play sports, carry heavy things, or work out, the stronger and thicker your bones will become. Unfortunately, in space, where the body is weightless, our skeletons feel almost no force at all. When bones are not used, they become thinner. That’s a problem for astronauts because they need those bones when they return to Earth. In fact, when astronauts return home, they have to take it easy at first so they don’t break their bones while they regenerate.
To help prevent muscle and bone loss, astronauts living on the International Space Station have to exercise for two hours every day. They strap themselves onto a stationary bicycle, use bungie cords to hold themselves down to run on a treadmill, or use a spring device that simulates lifting weights.
If you’ve ever wanted to be a little taller, though, space flight might be for you. Your spine is a long chain of bones separated by soft discs. These discs act as shock absorbers so that walking on Earth is not so rough. In space, there’s no downward force on your spine, so the spongy discs expand, pushing the bones of the spine apart. And what does that mean? It means you get taller by several centimeters. While that sounds great in theory, the expansion also pulls on nerves in the spine, which can cause uncomfortable back pain.