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Can You Survive In Space With Only A Helmet?

What does it actually take to survive in space? Is it the suit, is it the helmet? What is more important for an astronaut, and what item is more important to their survival? Fascinated by the topic, I spent time researching. Here is what you want to know.

So, can you survive in space with only a helmet? Technically yes, but only for a very short period – perhaps up to a minute at most. This is because the oxygen supply is in the suit; so you would soon run out of this essential gas and suffocate. Aside from that, the pressure of the atmosphere would cause severe swelling across the body, resulting in organ failure.

How the elements and physics of space operate are scary enough. 

But, making sure that you’re protected from head to toe during a spacewalk has many purposes for combating outer space’s unforgiving nature!

So, let us now delve much deeper into all that is required to survive in this perilous environment; it’s entirely fascinating – I promise!

Can You Survive In Space Without A Helmet?

Unfortunately, you’re not surviving a spacewalk without a helmet. You would immediately asphyxiate and lose consciousness within roughly 15-45 seconds. 

Since your organs are being starved for oxygen, you would die within a few minutes. 

Your head would be exposed to unfiltered UV radiation, and gamma radiation would start destroying your DNA. 

Your body would also be exposed as the tight seal between the helmet and the body has been separated. 

The first issue you’ll run into here is something called Eubillism, which is when bubbles form in the body’s fluids. 

This comes from the decrease in ambient pressure. 

Gas bubbles in your fluids will cause you to swell about twice your size, and although you’ll be pretty uncomfortable, don’t worry; you won’t explode. 

It also wouldn’t be a good idea to hold your breath to try and survive longer. 

It would be versus the vacuum of space trying to suck the air out of your lungs, causing them to rupture. 

Interestingly enough, some places in the solar system where you can take your helmet and survive. 

One of the most famous examples would be Saturn’s largest moon, called Titan. 

The moon has quite a few Earth-like elements and a surface pressure of 1.45 times that of Earth. 

You need about 0.5-5 times the air pressure of Earth to survive. 

Although you wouldn’t need the force provided by the helmet, you would need some kind of heat source, as the temperature on Titan is -290 degrees Fahrenheit.

So – don’t take your helmet off in space – it doesn’t end well!

What Do You Need to Survive In Space?

It’s imperative that Earth-like conditions are being simulated at all times to survive. The human body and general biology have evolved to survive Earth’s gravity and atmospheric conditions but not the vacuum of space. 

There’s are also psychological effects of being in space, specifically speaking, the suprachiasmatic nucleus. 

It has an impact on our circadian rhythm, our internal day and night schedules. 

When speaking of the International Space Station (ISS), the interior keeps the astronauts safe, providing them the conditions they need to survive as comfortably as possible. 

Even then, the ISS orbits the Earth in about 90 minutes, traveling at a speed of 17,150 miles per hour, covering five miles per hour. 

This causes the astronauts to have the feeling of jet lag nearly all the time. 

For a spacewalk, your suit will need oxygen and a system to remove carbon dioxide, maintain extreme temperature changes, protection from radiation, and even micrometeoroids which can quickly kill you. 

The astronauts will have to bring a sufficient amount of food to survive the voyage, ranging from an array of items. 

Water, of course, is also essential, not only for personal hydration, but many different foods will need rehydration to be edible. 

How much food is required is calculated quite precisely to ensure that there’s enough for the entire expedition. 

With a dedicated team of multi-talented astronauts, there’s a lot they can handle on their own, but they still need a team on Earth helping them along the entire voyage. 

To stay in contact, NASA has to use all three of their space communication networks. 

Orion, the space capsule that carries the crew to space, will switch from the Near Earth Network to the Space Network after entering cislunar space. 

Lastly, there’s the Deep Space Network for more distant spacecraft. These are all made possible by the Data and Tracking Relay Satellites. 

Of course, Orion has backups in place if any of its systems fail, including a new backup system called optical navigation.

A camera on Orion will take pictures of the Moon, Earth, and the stars to triangulate the position of Orion autonomously. 

Once you travel past the magnetic field of the Earth, you can now be exposed to harsh radiation, and this can cause damage to avionics, as well as other crucial equipment. 

Being exposed to large amounts of radiation can be highly damaging to the human body, causing radiation sickness and various forms of cancer. 

The spacecraft itself also has to be able to hold immense heat from the outside. 

When Orion re-enters Earth’s atmosphere, it will be traveling at a speed of around 25,000 miles per hour. 

So, the outside of the spacecraft will need to withstand temperatures nearly half as hot as the sun. 

As crazy as that may sound, NASA has the equipment to handle it. 

Orion has a heat shield with a special coating that can withstand temperatures of up to 5,000 degrees Fahrenheit.

Why Do Astronauts Wear Space Suits

The line between Earth’s atmosphere and outer space is called the Karman Line. Once you travel past this line into space, conditions are no longer habitable unless you have your spacesuit, of course, which comes with its much-needed PLSS or Primary Life Support System. 

This piece is the “backpack” unit on the back of the suit, providing pressurized oxygen and ventilation. 

It also removes water vapor and carbon dioxide. 

When it comes to the harsh changing temperatures of space, the suit has a sun visor and the suitable material to protect the face and body from intense heat and radiation. 

When the sun is in full view, the suit can feel the heat of 248 degrees Fahrenheit and -248 degrees when the sun is not in view. 

This can change very rapidly as there is no atmosphere in space. 

The human body requires a certain amount of air pressure to function correctly. 

Spacesuits provide this through inflating the suit; another reason the suit is airtight is essential. 

This is also required so that body fluids stay in a liquid form. 

When out a spacewalk, there is a slew of hazards to be prepared for. 

One of the most dangerous being meteor dust or micro asteroids. 

Meteor dust is orbiting the Earth all the time, traveling at a speed of 14,912 miles per hour; it can do quite substantial damage to the spacesuit. 

There’s protection built into the suit called the Hard Upper Torso, acting as armor against these dangerous micro asteroids. 

Sometimes, spacewalks can last for hours, the longest recorded at almost 9 hours long. 

So, astronauts need a way to eat and drink while outside the spacecraft. 

There’s a water compartment in the suit for dinking and a high-calorie bar in the helmet. This is fixed close to the mouth for easy access. 

Do Astronauts Have to Wear Space Suits All the Time?

Astronauts only have to wear their spacesuits during spacewalks or during launch and re-entry. 

Additionally, there are different suits for different purposes. 

The suit used for spacewalks is equipped with loads of equipment to protect the human body from hard radiation, temperatures, and potential debris while providing proper oxygen, ventilation, food, and water. 

When it comes to launch or re-entry into Earth’s atmosphere, astronauts wear a semi-pressurized suit as well as a parachute pack. 

Inside the suit are bladders that automatically fill with air to combat the effects of low cabin pressures. 

This causes blood to pool in the lower body, which would cause the astronaut to pass out, and the air-filled bladders prevent this from happening.

During spacewalks, astronauts use a suit called the EMU or the Extravehicular Mobility Unit. 

Even though they can cost up to $12 million each, they are deemed cost-effective because they can be reused and have interchangeable parts to fit different body shapes and sizes. 

For mobility and more control, a nitrogen-propelled backpack called the MMU or Manned Maneuvering Unit can be attached to the EMU.

Astronauts are free to wear their regular clothes inside the spacecraft, as their internal environment is built to livable conditions. 

Astronauts must double-check their suits top to bottom before a spacewalk, as there is nearly zero room for error. 

It can take 15 minutes to put a suit on and the same amount of time to take off, so most astronauts prefer not to return to the spaceship for just a snack or to use the restroom. 

A primary reason for the water and convenient food available within the EMU itself, as well as a way to relieve yourself if you need to use the bathroom.

With all the equipment, technology, and engineering that goes into these suits, it doesn’t take much for things to go wrong. 

Luckily, precautions and multitudes of backups are ready to protect our astronauts, whether on a spaceship or on an 8-hour spacewalk.