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How Do Astronauts Communicate In Space?

You would think that communicating with your fellow astronauts while you’re up in space is no problem at all. In fact, you’d probably think that it’s as easy as it is on Earth. You simply open your mouth and relay the words. Well, the view might be good for astronauts up in space, but the reality is that they won’t be able to talk about it as if they were here on Earth. Space is a whole different ball game when it comes to socializing activities. Does this mean that astronauts don’t communicate at all? Are they forced to give each other the silent treatment? No, of course not. That wouldn’t be practical at all for anyone. Astronauts do communicate up in space, but the question is how?

So, how do astronauts communicate in space? Astronauts communicate in space by using a Communications Carrier Assembly (CCA), which is installed in their space suits. The CCA consists of microphones through which astronauts can speak and listen to one another via radio communication. Natural communication can’t occur as sound waves are unable to travel through space due to there being no air up there. Fortunately, radio waves can travel through space despite the absence of air.

Amazing, right?

And it gets even more interesting.

So sit back, relax and keep reading, and you’ll find out why!

Can Astronauts Speak To Each Other In Space?

Astronauts cannot speak to each other in space just by using their voices and ears. However, they are able to communicate with one another up amongst the stars with the help of technology.

So they can…but they can’t. At Least not by themselves. 

Now it’s important to note that we are not talking about communication inside the space station. Astronauts can talk normally without the assistance of technology…well, kind of without the existence of technology. 

They’re able to communicate inside the space station because there is air there. Air which is provided by technology on the station, but it still means they can talk naturally.

But it’s when astronauts exit the space station that they find they cannot communicate with one another naturally.

You see, the problem that astronauts would run into when trying to have a chat up in space is that there is no air up there.

Sound waves, which we can generate through talking, need air so that they transport through it.

If sound waves cannot transport through space, then they won’t be able to reach our ears, which are integral to the hearing process, funnily enough.

It doesn’t matter if you’re shouting at the top of your voice. If there’s no air for those sound waves to travel through, then your voice won’t get the person you are trying to communicate with.

Now, this sounds like a big, big problem for astronauts. There are all sorts of dangerous situations that could arise from them not being able to talk to each other up in space.

For example, how will they warn each other about the aliens sneaking up on them? 

See what I mean? It’s essential that astronauts communicate.

But they can’t…at least not with their own natural tools, as in their voices.

Fortunately, astronauts are able to communicate with the use of technology. Without this, they would not be able to.

So, what’s this technology they use to communicate with? Time to find out

How Do Astronauts Talk In Space?

Astronauts talk in space by using a Communications Carrier Assembly, which is installed in their space suit. It consists of microphones through which astronauts can speak and listen to one another via radio communication.

So, we know that astronauts can’t talk normally up in space. But at the same time, we know that it is essential that they communicate up there.

So how is this conundrum resolved? Well, although radio waves cannot travel without air in space, they can be picked up by radio receivers. This is a vital stroke of scientific luck!

Astronauts, as you know, have to wear these big protective suits when they venture outside the space station they are on. These suits protect them from the deadly cold temperatures of space and also provide them with an oxygen supply. But that’s not all they do.

Space suits also possess what is called a Communications Carrier Assembly (CCA). This is a fabric hat that is fitted with microphones so that astronauts can both speak and listen via radio communication.

It doesn’t matter how close the astronauts might be floating next to one another; without the CCA, they won’t be able to communicate.

If the CCA malfunctions, they might need to start doing sign language…which isn’t part of their basic training as far as we know.

But it’s important to remember that astronauts don’t need to use the CCA when they’re inside the space station. There’s air inside the station, which means the sound waves from their voices can travel.

NASA is always looking to improve the method through which their astronauts communicate. 

There are a few disadvantages with the current CCA system, including that they are susceptible to interference caused by sweating, and they also cannot be adjusted out in space as they are trapped underneath the astronaut’s helmet.

The future seems to be an integrated audio system that would be built directly into the astronaut’s space helmet.

Can Astronauts Talk In Space Without Any Device?

Astronauts cannot talk in space without a device whilst there is no air for sound waves to travel through. This means that astronauts can’t communicate when outside of the space station, but they can when inside as there is a supply of oxygen that sound waves can travel through.

Yep. We really are relying on radio waves here, folks.

When I said sound waves need air to travel through, I meant it.

Although it’s not just air, the scientific phrase we use is a medium for propagation. 

This can be air or water or whatever, so long as it classifies as a medium for propagation.

Without a medium for propagation, sound waves cannot travel. 

In space, there is a vacuum. Which means there is nothing. No space. No water. No medium for propagation. This means that astronauts cannot communicate via their own voices when out in space at all.

They will have to use technological devices, in most cases CCA, to communicate in space.

Now, this is only the case when astronauts are outside of the space station.

When they’re inside the space station, there is a medium of propagation, which is air. 

You’ll probably remember seeing pictures of astronauts onboard space stations without space suits on.

That’s because they don’t need to protect themselves from space’s hostile temperatures and also because they can breathe.

The space station provides a supply of oxygen inside its walls, meaning astronauts can breathe naturally without their space suits on.

As there is oxygen inside the space station, sound waves have a medium of propagation through which they can travel through.

Astronauts can therefore communicate inside the space station without the assistance of any technological device.

FUN FACT: You might have realized by now that astronauts can hear their own voices when inside their space suits. This is because there is a supply of oxygen in there, through which the sound waves in their voice can travel through. So if they feel like chatting to themselves, they can fill their boots. But they might find the other astronauts mute them on the CCA system when they become annoying. 

So, to summarise! 

Communication outside of the space station DOES require assistance from technological devices.

Communication inside the space station DOES NOT require assistance from technological devices.

Can Astronauts Talk To People On Earth?

Astronauts can talk to people on Earth through a variety of methods. These include radio waves communication and, believe it or not, social media.

That’s a relief! How on Earth would astronauts be able to check the score in the game…wait! I mean, how would astronauts be able to catch up with their families?

Luckily astronauts have plenty of methods for communicating with us folks back here on Earth.

There are three primary methods of communication between astronauts and Earth. Let’s take a look at each one.

Radio Waves Communication

They use radio waves to communicate with one another, but they also use them to communicate with people on Earth as well.

It makes sense, really. Although there is a medium of propagation, that being oxygen, on Earth, there are still obstacles to no medium of propagation up in space.

To be honest, this is irrelevant anyway, as the distance between astronauts in space and people on Earth is so vast that not even the astronaut with the loudest scream could be heard.

So, radio waves also aid Earth-to-space communication. By using radio waves, messages can be sent and received between satellites both situated on the space station and on Earth.

It’s a fantastically efficient method for long-distance communication, which is by it is the primary method used for communication between astronauts and mission control.

It’s also how astronauts will communicate with loved ones. But there is another method for doing this as well, which is…

Social Media

Whatever you may think about social media, one can’t deny how useful it is for astronauts.

Whilst up in space, they can use it to easily communicate with people on Earth, sending and receiving photos or status updates via the internet

Some astronauts tweet their adventures for the world to see. 

But for obvious reasons, this isn’t a method really used for communication between astronauts and mission control.


There you have it.

Whether or not astronauts can communicate with each other depends on the presence of a medium of propagation.

Human invention has found a way for astronauts to overcome any obstacles faced when looking to achieve efficient communication in the cosmos.

But if they do get fed up with talking to each other, astronauts can always have a chat with a random follower on social media!

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