Space is a mystery and a fascination to most of us. We read so much information about living in space and the effects that space can have on the human body that we do not always know what to believe.

In the video below, retired astronaut Chris Hadfield debunks common space myths and answers the questions that will help us understand what it is really like to live in space.

Astronaut Chris Hadfield Debunks Space Myths

The questions below summarise common misunderstandings that people have about space.

1. What Happens To A Person In Space Without A Space Suit?

After about 10 seconds or so, your skin and the tissue underneath will begin to swell as the water in your body starts to vaporise in the absence of atmospheric pressure. You won’t balloon to the point of exploding, though, since human skin is strong enough to keep from bursting; and, if you’re brought back to atmospheric pressure, your skin and tissue will return to normal.

Because you will be exposed to unfiltered cosmic radiation, you can expect some nasty sunburn, and you’ll probably also get a case of decompression sickness.You would not, however, freeze straight away, despite the extremely cold temperatures; heat does not leave the body quickly enough for you to freeze before you suffocate, due to the lack of both convection and conduction.

f you do die in space, your body will not decompose in the normal way, since there is no oxygen. If you were near a source of heat, your body would mummify; if you were not, it would freeze. If your body was sealed in a space suit, it would decompose, but only for as long as the oxygen lasted.

2. Do You Need To Exercise In Space?

On Earth, except while sleeping, human beings are always moving against the force of gravity, with their muscles and bones supporting their body. In space, however, the body does not need to do this supporting work, since there is no force of gravity. This has an adverse effect on the body with the bones and muscles becoming weaker.

In order to keep the body working, the astronauts need a proper amount of exercise. They will exercise approximately two hours every day using exercise machines, such as treadmills and ergometers.

The treadmill is a machine on which, the astronauts do running exercises with their bodies strapped to it. The Ergometer is a machine similar to a bicycle without wheels. The amount of exercise can be adjusted by changing the pedal’s pressure.

Exercise is an important part of the daily routine for astronauts aboard the station to prevent bone and muscle loss. On average, astronauts exercise two hours per day. The equipment they use is different than what we use on Earth. Lifting 200 pounds on Earth may be a lot of work. But lifting that same object in space would be much easier. Because of microgravity, it would weigh much less than 200 pounds there. That means exercise equipment needs to be specially designed for use in space so astronauts will receive the workout needed.

3. Does Space Have A Smell?

Though a pure, unadulterated whiff of outer space is impossible for humans (it’s a vacuum after all; we would die if we tried), when astronauts are outside the ISS, space-borne compounds adhere to their suits and hitch a ride back into the station. Astronauts have reported smelling “burned” or “fried” steak after a space walk, and they aren’t just dreaming of a home-cooked meal.

The smell of space is so distinct that, three years ago, NASA reached out to Steven Pearce of the fragrance maker Omega Ingredients to re-create the odor for its training simulations. “Recently we did the smell of the moon,” Pearce says. “Astronauts compared it to spent gunpowder.”

4. Will Travelling At The Speed Of Light Prevent Ageing?

When traveling at speeds near the speed of light special relativity says that time is dilated. Thus relative to another inertial frame (where perhaps a stationary twin sits) time for the moving twin is slowing down. Hence the stationary twin is aging faster. While the moving twin remains in an inertial frame (that is, continues to move at a constant velocity) the moving twin will observe time running slower for the stationary twin. If they could ever be at the same place and the same point of time again, someone would have to be wrong! This is the Paradox.

The rub is in trying to get the twins back together at the same place and the same time so they can compare their ages. That’s the ‘return’ in your question. This will necessarily require a change in velocity — hence an acceleration. But an accelerating frame is not an inertial frame. Thus, without knowing the details of how we bring the twins together, there really is no way to say for sure who will be older — but in most cases it will be the travelling twin.

5. Do Explosions Make A Sound In Space?

In empty space, there is no air, and what we call “sound” is actually vibrations in the air. Now, like you’ve said, there are indeed light waves and radio waves in space, but these waves are not sound, but light. Light does not need air to travel, but then you don’t hear it; you see it, or it is interpreted by your radio set and then translated into sound.

Astronauts in space do talk to each other. In the spacecraft, there is plenty of air, so they just talk normally. When they are spacewalking, they talk by means of radios in their helmets. The radio waves, again, have no problem in space, but they’re not sound. They’re radio, which has to be converted into sound by the astronauts’ headsets.

So say you were in a spaceship in the middle of a big space battle and a nearby ship exploded. The exploding ship would release gases and technically sound could travel along with them. However, since space is a vacuum, these gases will spread out very rapidly and the density will drop off very fast with distance from the explosion. (If you think about it, the amount of air in the ship is probably not very large compared to the volume of space between two ships.) So by the time the explosion reached your ship nearby, any sounds carried by the gas would still be too faint to hear.

6. Is Spinning A Ship The Only Way To Create Gravity?

If you change the velocity of the spacecraft, you will have an acceleration. If this acceleration is in the direction from the feet to head of the astronaut, there will also be a force from the floor pushing up and the astronaut will feel an apparent weight. Of course it would be quite difficult to continue to accelerate by speeding up for a significant time (but not impossible).

There is another way to have an acceleration for an astronaut and it has to do with the vector nature of velocity. The acceleration depends on the change in velocity. Since velocity is a vector, changing either the magnitude or the direction of the velocity will result in an acceleration. Boom. There’s your answer. If you just move in a circle (at a constant speed), you will change direction all the time and be accelerating.

7. Is Nasa Working On Warp Speed?

Ever since the sound barrier was broken, people have turned their attention to how we can break the light speed barrier. But “Warp Drive” or any other term for faster-than-light travel still remains at the level of speculation.

The bulk of scientific knowledge concludes that it’s impossible, especially when considering Einstein’s Theory of Relativity. There are certainly some credible concepts in scientific literature, however it’s too soon to know if they are viable.

Science fiction writers have given us many images of interstellar travel, but traveling at the speed of light is simply imaginary at present.

In the meantime, science moves forward. And while NASA is not pursuing interstellar flight, scientists here continue to advance ion propulsion for missions to deep space and beyond using solar electric power. This form of propulsion is the fastest and most efficient to date.

There are many “absurd” theories that have become reality over the years of scientific research. But for the near future, warp drive remains a dream.

8. Can You Survive Interstellar Travel By Freezing Yourself?

It is impossible to prove experimentally that the ideas of the cryonists are possible as no one has learned to revive people yet. Although it has already been proved, for example, that if you freeze threadworms alive, they retain conditioned reflexes after awakening (if they survive, of course — this is not possible for everyone). But many scientists consider such experiments unconvincing. “In my opinion, this is a purely commercial exploitation of the dream of an afterlife,” said Yevgeny Aleksandrov, Ph.D. in Physical and Mathematical sciences, the head of the RAS commission which stands up to the pseudoscience. “Mankind will hardly ever find a cure for all diseases because it means the recipe for immortality. I don’t believe in eternal life and suppose that it would be terrible: the evolutionary process will stop”.

9. Can You Fly Into The Stratosphere With A High Altitude Balloon?

Weather balloons can rise to an altitude of 24 miles (39 kilometers) or more before they burst, and a payload may land (via parachute) up to 75 miles (120 km) away, depending on wind conditions at the launch site, Maydell said.

Though outer space doesn’t technically begin until you get 62 miles (100 km) above Earth’s surface, the views are still great from 24 miles up. At that altitude, the sky is black and the curvature of the Earth is clearly visible, Maydell said.

“It’s about the closest an average person can get to being in space, and you can do it for about the price of a nice iPad,” Maydell said.

10. Will Your Body Grow Taller During Space Travel?

Astronauts in space can grow up to 3 percent taller during the time spent living in microgravity, NASA scientists say. That means that a 6-foot-tall (1.8 meters) person could gain as many as 2 inches (5 centimeters) while in orbit.

Past studies have shown that when the spine is not exposed to the pull of Earth’s gravity, the vertebra can expand and relax, allowing astronauts to actually grow taller. That small gain is short lived, however. Once the astronauts return to Earth, their height returns to normal after a few months. But still, scientists haven’t been able to examine the astronaut’s spinal columns when experiencing the effects of microgravity until now.

11. Does Bacteria Multiply Faster In Space?

The E. coli in space showed a 73 percent reduction in their volume, giving the bacteria much less surface area that can be exposed to antibiotic molecules, Dvorsky reports. Along with this shrinkage, the cell membranes of the E. coli grew at least 25 percent thicker, making it even harder for any antibiotic molecules to pass through them. And the defense mechanisms weren’t only the individual level—the E. coli also showed a greater propensity for growing together in clumps, leaving the bacteria on the edges open to danger, but insulating those within from exposure to the antibiotics.

All of these differences allowed the E. coli on the International Space Station to grow to 13 times the population of the same bacteria grown on Earth under the same conditions, according to the study. And understanding why and how these defense mechanisms form could help doctors better prevent the scourge of antibiotic resistance here on Earth.

Perhaps even more terrifying, compared to the bacteria grown in the same conditions on Earth, the space-bound E. coli developed fluid-filled sacs called vesicles on their cell membranes, giving them tools that can make them even better at infecting other cells. This means that astro-bacteria could make people ill more easily, creating an infection that is harder to treat.

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