How Astronauts make Oxygen in the space from their bodies.
Introduction.
So, imagine you’re an astronaut on International Space
Station, looking out the window, and you’re craving a pizza. Pepperoni. Cheesy.
Umm. Let’s say it’s possible to order delivery. What would that bill look like?
I’ll just put it this way: sending 1 lb of cargo into space costs about
$10,000! Not including tip! So, how do space agencies afford to send supplies like
oxygen, water, and food to their astronauts?
Do they send it with the crew?
Before they found a more efficient solution, they’d pack all
the water into space with them in their rockets. The water took up a lot of
room that could ’ve otherwise been used for other supplies. That, and the added
weight wasted fuel. So short answer: nope, it doesn’t go with the crew from the
get-go. – That means they deliver it, right? Eh, that’d be too risky…and
expensive! There’s no 100% guarantee that something bad won’t happen to the
cargo ship at launch or on the way to the International Space Station. (Like,
space pirates?) If the cargo doesn’t get to the station, then the next delivery
will have to wait a very long time. That’s not an option since it’s dangerous for
the astronauts. Ok, so let’s break it down item by item. First, where do
astronauts get their… – Water The primary source of water for the crew is… the
astronauts themselves! Whether it’s drops of sweat, condensation from
breathing, or going to the toilet, all this water gets processed through
complex filtering systems.
When it comes out, it’s clean drinkable water. Yes, you
heard that right: astronauts recycle…their own body’s H2O! In fact, 85% of
their “tinkle” can be turned into clean water! (off mic) We can say “tinkle”,
right? [ding] Okay. (back on mic) Sorry just checking with Mr. Strudel meyer,
the sensor. We’re cool. Water in separate cargo deliveries is still sent to the
ISS. But with the invention of the onboard Water Treatment System (WRS),
everything has become much simpler. And with the help of a process called
electrolysis, they’ve learned how to extract the necessary reserves of oxygen
from the water itself! But more on that here in a bit. For now, let’s see… –
How the WRS works The astronaut goes to the toilet and flushes it all down. The
[sensor’s honk], pardon me……the liquid contents fall into a compartment that
rotates very quickly and works like a centrifuge. This centrifuge is then
heated. Under c pressure and high temperature, the liquid evaporates and
collects condensation in an external chamber. From there, the condensed water
enters a tank.
All other moisture
from the ISS – sweat and exhaled air – goes to this same tank. From there, the
water enters a separator where the liquid is cleaned of doors. After going
through several levels of filtration, it gets heated once again and
disinfected. And, presto – clean water is ready! After knowing that, do you
think you could live on the ISS? Let me know down in the comments! Ok, moving
on to… – Oxygen Ah, the question of the day! Like I briefly mentioned, they can
get oxygen from that same water. Remember your chemistry classes in school?
Oxygen is the “O” part of H2O. Here’s how they do it: an electric currentis
passed through water molecules to break them down. This process is called
"electrolysis." So after that, you’ve got 2 hydrogen atomsand 1 pure
oxygen atom. They collect those now separated oxygen molecules in special
cylinders, and astronauts can breathe easy!
But where do the remaining hydrogen
molecules go?
They’re also used to the maximum benefit of the entire crew.
Through something called the Sabatier reaction, they mix the hydrogen with
carbon dioxide (the stuff you’re breathing out right now!)to create… water! Incredible,
right? So, the ISS is completely independent of the Earth as far as its water
and air reserves go? Unfortunately not. Thanks to this complex system, it’s
possible to produce a little over 4 lb of oxygen per day. That’s only enough
for 2 people. The ISS crew usually consists of 6. To make up the difference,
oxygen is delivered from Earth. So, what about… – Food Here, the ISS is
entirely dependent on supplies delivered from Earth. All those freeze-dried
packets of astronaut food go along with the crew when they head to the station,
or separate cargo is sent. But you’d be surprised by the number of options they
have.
According to NASA, astronauts dine on fruits, nuts, chicken,
beef, seafood, candy, and even brownies! They also have coffee, tea, juices,
and lemonade. But why can’t they plant an indoor garden on the station to eat
fresh fruits and veggies? Well, it’s not as easy as it sounds. How can plants
grow in the vastly different conditions of outer space? There’s no gravity, day
and night are all over the place (the ISS sees 16 sunrises and sunsets each
day!), the air is dry, it’s cold. Plus, the ISS might be as long as a foot ballfield,
but it’s not like they have a lot of room for a sprawling garden. Well, the
good news is, they’ve already figured out a solution to all this, and
astronauts are growing food up there! In 2015, members of the 44th ISS crew
atelettuce that was fully grown on board! The seeds had been sent from Earth.
Once in the station, they were put in a Veggie box with red, blue, and green
lamps that each provided a certain growing condition for the seeds. The
experiment was successful, and the astronaut seven said that the lettuce tasted
exactly the same as it does on Earth! Their next crop idea? Tomatoes and
cucumbers to go with that space salad! – What do they do with their trash? Just
like you and me, astronauts have garbage too. Disposable utensils, used towels,
raw materials, empty food packets – you name it! You’d think they could just
chuck it out into the endless void of space, but that would be littering!
Whenever they get a delivery, the cargo ship is docked to the station. The
astronauts get what they need from it, and then they load this ship with their
trash. After a few weeks, the supply vehicle is disconnected from the station,
and it heads back to Earth. It might make it to the surface or burn up in the
atmosphere. In short, astronauts don't litter! – Then where does space debris
come from? Right now, there are tons of satellites floating around Earth. You
have them to thank for your GPS or satellite TV. But there are so many of these
things up there, that they sometimes crash into each other. Their remains
create space trash. In addition to them, the uncoupled parts of launch vehicles
become garbage too. This garbage, seemingly harmlessly soaring in outer space,
is a serious threat to the ISS. Even a dime-sized fragment of a satellite can
penetrate the station's casing and lead to major problems. In all of the ISS’s
21 years, the station carried out 25 maneuvers to evade space debris. Plus, the
station is covered with protective plates that guard against a tiny piece of
debris shredding through it! – From the ISS to Mars! The cool thing about the
International Space Station becoming more and more self-sufficient is that it’s
almost like a trial for larger missions in the future. I’m talking about
colonizing the Red Planet, baby! Instead of being a “mere” 250 miles from Earth,
we’d be 140 million miles from home! That means deliveries (and trash dumps!)
won’t be an option! So,
what will they do with their garbage?
Two words: – Waste recycling The plan is to process all
garbage using the "liquid combustion" system. Simply put, organic and
inorganic waste would be collected, crushed, and mixed with hydrogen peroxide.
After a day, an electric current is passed through this mass, and the oxidation
reaction starts. All the garbage will be stored in a device, where they’ll put
a colony of microorganisms. They eat the trash and emit free electrons as a by product.
Electrodes and a battery will be connected to the device, which will accumulate
energy.
You know what all that means? Scientists have learned how to
recycle garbage and turn it into electricity with the help of germs! That
battery can hold a charge of 400 hours, after which the bacteria will need to
be replaced. If this all just sounds hypothetical, they’ve already pulled it
off here on Earth in terrestrial conditions. The next step is to try it out in
space! Besides creating electricity with the help of bacteria, recycling waste
will also be good for gardening since it’ll contain nutrients and minerals for
the plants! (off mic) Oh, hey thanks Mr. Stude lmeyer![ding] Sure glad I didn’t
say P[honk]. Oh well… (on mic) Hey, if you learned something new today, then
give the video a like and share it with a friend! And here are some other cool
videos I think you'll enjoy. Just click to the left or right, and stay on the
Bright Side of life!

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