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So one
more try.
OK, at least I'm getting audio on my
monitoring and here, so.
I'm very sorry, it seems like the
obvious finally started
dying on us after having run
for like one and a half
weeks straight.
So there's a technical limitation of
what we can do.
I'm very sorry about that.
Let's hope that now everything works
fine again.
Our technical person in the background,
Daksh was fixing stocks now
has full control again and will hopefully
switch back to Earth.
So and you can just
start again again.
Very sorry.
OK.
No worries. OK.
Hello, everybody. And
now we had a little bit of a chance
to see my beautiful,
but now the old who is working, so I
shall start and this talk, I'll
give you an overview of spacecraft
life support systems, maybe a
more in-depth overview than you ever
cared about, but that is how I roll.
So here we go.
I'm worse, I'm sitting
in Finland right now, as you can see
behind me, I'm sitting in a wooden hut
next to a lake where the lake is frozen
over, and I've been sitting here since
March to keep my distance
from people because it's the farthest I
could be from people without actually
going to space.
And the whole time I'm giving is
basically a Part three in this year.
The first one I gave in 2013 at the Glass
program here in Germany.
How to fly spacecraft, which was
basically orbital navigation.
Then there was the second possible
Typekit spacecraft in 2016, also in
Germany, which talked about materials
and how to get it all to space and how to
keep it together.
And now this is part of how to survive in
spacecraft, concentrating on life
support systems in my
normal everyday job.
I mean, space physicist I do big
plasma physics simulations of the new
space, magnetic field, solar, wind and
so on.
But that's not what I'm going to talk
about you.
All right. So where are we at?
We are in a spacecraft.
We are outside the atmosphere, which
means there's no air, no pressure.
There are cosmic rays hitting us.
There are temperature fluctuations.
Micrometeoroid is running around and all
these kind of things.
For most of these, especially the cosmic
rays and micrometeoroid, you can go back
to the talk about how to build spacecraft
because you basically just need something
shooting to get around.
But this will especially focus on
the fact that we are outside the
atmosphere and you need
to somehow bring your own air
that you can breathe.
So what does the life support system
actually do? I mean, it gives you a life,
but what does a human need to
be like on average?
And this is from a massive statistics
page. One human on a space station
consumes 830 grams
of oxygen, but doesn't actually seem like
much because it's not very
heavy.
This corresponds to about 12 liters of
oxygen or the economic pressure.
But of course, you are breathing in much
more air. The air that you breathe only
contains a small amount of oxygen, and
when you're breathing it out, a little
bit reduced.
So about you only once you mate the 30
grams of oxygen per day,
you also eat food.
And the average estimate is about 620
grams of food per day. This is very
strongly from person to person.
And you drink water, and
these three point five kilograms are not
just water that you drink.
So few people drink three and a half
liters of water. This is also air
moisture, the jobs or to your lungs.
This is the overall water balance that
you put into your body, and
your body does all kinds of funny things
with it, and it produces output about
one kilogram of CO2.
You notice already.
You breathe in 800 grams
of oxygen and you get out one kilogram of
CO2, so this carbon atom is like
a transfer from the food, so your
metabolism into the CO2,
then you lose about
100 10 grams of what knots equals
metabolic solids.
So that's the stuff you drop in the bowl
and then you produce.
Flewitt is an output, and that's
Europe, and you can see all here that
the Moss has increased a little bit
because some part of your food with salt,
for example, goes into urine and then
some other products, metabolic
products that people.
So the job of your life support system is
to supply the stuff on the left and
get rid of the stuff on the right.
In a way that does not make you
uncomfortable.
It also needs to keep the temperature in
the comfortable range and keeps notes
away, especially ones that are
involved with it.
Bottom two things on the right.
Now, let's talk with air,
we want to have
reasonable air.
And on Earth, we hear
around us what one bar of
it is refreshing and that is consisting
of different things, and now I'm talking
specifically about partial pressures
here. So when we have this one bar
of ambient pressure around us,
78 percent of that is nitrogen.
I'm talking just 0.78 bar
nitrogen, 21 percent oxygen,
one percent others, especially that's
helium, CO2, argon, these
smaller constituents of the atmosphere.
You can also just as easily
leave out the nitrogen and
run in in in an atmosphere that's
entirely on the oxygen.
But then you need to have a much lower
pressure because otherwise you get oxygen
toxicity.
The other way round.
You can also reduce the oxygen amount
in the air, but then it gets quickly
problematic as soon as you go under
about zero point one five bar
of oxygen, partial pressure, you get
headaches, it's loss of concentration.
And then if it goes even further down,
starting at around 0.1 to a bar,
you get unconsciousness and death.
So you don't want these factors
this this.
Boundaries here are quite specific
from person to person and especially
people that live high in the mountains,
in the Andes or the Himalayas.
They have a much higher
tolerance for low oxygen demand because
they produce more red blood cells
and so on.
Then this is something I heard in the
talk a while back.
The first symptom of hypoxia is
consciousness, and that is a problem.
If the oxygen amount goes
down slowly, you get headaches and
you'll notice that you only see black and
white. But if your oxygen content rises
quickly or slowly falls down quickly,
you will not notice your missing oxygen
until you pass out.
And then it's too late to act.
So it's really important that the system
keeps this on a good level.
This already sets breathing without
nitrogen isn't a problem.
You can just reduce pressure and only
have 0.1 oxygen, which
is, for example, what you do in
spacesuits.
If you do that in the spacesuit, they're
much less baloney and much easier to move
in, so you have lower pressure.
But the disadvantage of this is that you
then have a pure oxygen atmosphere and
you will have lots and lots of increased
fire risk stuff that you would normally
not expect to ignite ignites suddenly
in the pure oxygen atmosphere, for
example, aluminum or.
Plastic or any
kind of thing that can burn will burn.
The Americans learned this quite
uncomfortably in Apollo one, which had a
disastrous fire accident on the launch
pad before takeoff.
Well, three estimates died.
So because of this, you try to
avoid oxygen out in space as much as
possible and try to work in, well,
imitating what you have both at
sea level.
Now, how do you do this?
How do you supply air that you can be?
The obvious and easiest way to do this is
to just take air and compress it
in a bottle and breathe directly
from the bottle via a pressure regulator.
So you get air to breathe that and then
you breathe it out. And since you're in a
spacecraft, you can just be the in space
and gas it off.
And that works quite OK.
This is like the diving apparatus,
the disadvantages in this bottle, you
have 78 percent nitrogen, so
that does actually nothing to your
breathing. You're just wasting mosquito
and in space like you always want to have
stuff as light as possible not to waste
moths.
So it would be much nicer to somehow
recycle the air that you breathe out
because you're breathing in 21 percent
oxygen and you're still breathing out
about 14 percent.
So why not reduce that oxygen?
But you've just based on?
So this system is impractical for more
than a few hours of spaceflight and
actually no spacefaring nation
has ever used the system like this
already the first Mercury flight of the
Vostok system in
honor of the Russians, also the Chinese
capsules, all of them are already using
more advanced systems.
As far as I know, some of the commercial
space space planes are
now employing simply this method.
If they're just doing it properly, fly
for a couple of minutes.
Fine.
But you should go beyond that right away.
Better oxygen sources you can use, for
example, 100 percent compressed oxygen,
you just use an oxygen bottle and breathe
on that.
Right now, watch out, though, if you're
not careful with this, then you have an
explosive.
This is a picture of a life support
backpack from an American extravehicular
mobility unit in
the beginning of the shuttle program,
where this was just being developed and
tested.
And you can see the oxygen bottle
on the site was feeding oxygen
into the pressure regulator here at the
bottom, and that was made out of aluminum
and it caught fire and the entire thing
exploded.
Two people got hurt.
Nobody.
Fortunately, died, but
that means that even Nazar who are
building these professionally have to
sometimes find out that they are not
careful the same design, despite
the waste that they just replaced as one
regulator. And ever since then, the same
life support pack has been used in the
shuttles and the International Space
Station ever since.
Now there's an even better oxygen source,
and that is.
Called a oxygen candle.
In this, depending
on who designs this, either if it's a
Russian design, yes, sodium chlorate
or for the US systems, you have lithium
chloride packed with iron
powder.
And if you ignite, that's if you
heat it up at one ignition point high
enough, they start to burn.
This sodium chloride
just decays to
basically, that's a redox reaction to
normal table salt rust
powder. And then there's two oxygen atoms
left, and so that goes
out of the system and supplies oxygen.
So this is a compact,
solid device that you can switch
on by igniting it at one end, and then it
slowly burns to over multiple hours.
So this design, for example,
burns for eight hours and supplies
oxygen for three people for eight hours,
which is very nice because then you don't
need to care about pressure regulation
and so on. Just ignited on one end, and
it's replaced with oxygen.
This is actually typically used in
space stations as the backup system.
Here's a picture from the old Mir space
station, where one of these oxygen
candidates was just being taken into use
next to the regular life support system.
This very much up here is also
the point where the fire broke out
on the space station Mir at the
middle of the 90s, which eventually
caused the space station to be
decommissioned. Because this thing gets
very hot on the left, you see
the labeling on one of the American
oxygen candles hot surface activated.
They get up to 500 degrees or so.
So you need to be careful with that, but
it's a very nice way to produce oxygen
without needing any further equipment.
These are typically used as the backup
system for the more complicated ones that
we're getting to next.
Now, before we go through the more
complicated ones, however, we have to
talk about the second half.
You remember the initial looks like you
have oxygen coming in and then the humans
breathe CO2 out.
So what do we do with the CO2
just bringing oxygen doesn't make
it for life support system it.
If you have too much CO2, if you, for
example, don't care about removing it
collects in the spacecraft and did
partial pressure of CO2 will rise in
price and you will get lots of problems
starting from 10 millibars partial
pressure and that's much lower than the
O2 pressures you have before you start
to tire.
You have concentration problems, you get
tingly fingers and so on,
and then starting from about 70 millibars
again, you have loss of consciousness and
death, so you want to do something
about it before it gets so far.
And what can you do against CO2?
The straightforward method is chemically
binding. It's the so-called
CO two scrubber approach.
You take
CO2 and put it into water and it forms
carbonic acid. You all know this from
fizzy drinks. That's just CO2 will
dissolve water carbonic acid.
If this is an asset you can neutralize,
so you just let
your CO2 flow through a container that
contains some sort of basic
material. For example, lithium hydroxide,
you can also use potassium hydroxide.
But lithium is a very favorite
element in space flight because it's so
light.
So your CO2 reacts with the lithium
hydroxide and it produces water
and it produces lithium carbonate,
and then the CO2 is gone from your
system.
These canisters look, for example, like
this. This is one from the Apollo
command module where you have one site
where the eye gets pushed in by a fan
flows to the to the surface in
there with this lithium hydroxide, and
then it comes out purged of CO2.
These canisters, indestructible
shapes are working to remove
the Earth that one person, except for a
couple hours. So this one, for example,
had to be replaced every 12 hours in the
Apollo flights that lasted three days.
They had just had enough of the balloon.
But again, this is not yet a renewable
system.
And in the Apollo flights, there was an
additional problem.
In the flag of Apollo 13,
there was an explosion on the way to the
Moon.
This was actually an oxygen tank that
exploded, but not one of oxygen
for the life support system, but one
that was supposed to fuel the fuel cells
for the electrical system.
So the electrical system was gone and
they couldn't use the command module
anymore, and the astronauts would all
have died. If not, they had
the lunar lander attached to the
spacecraft. So they evacuated to the
lunar lander and were just living in
there while they were flying around the
moon and back to Earth.
The problem with that is that the lunar
lander was designed to support two
people for two days.
And now it had three people for three
days.
So it's lithium hydroxide canisters
simply were full before
before plant and there was no backup.
They brought the canisters from
the main command module and
found that actually, since this is a US
government spacecraft, the command
module and the lunar lander were built by
separate contractors, and these
contractors were not talking to each
other. So they used very different
design of their canisters, and these did
not fit together.
So the thing on the right was what they
would have needed to put into the lunar
lander life support system.
But those were full, so they only had the
ones on the left.
And then they had to get creative, and
which for me is the best proof
that you can fix everything with gaffer
tape if you only have enough of it.
So they built an adapter out of some
space spacesuit horses and a small
ventilator, a book to cover lots of
gaffer tape around the lithium
hydroxide canister.
And then they plucked it into the life
support system in the back.
You still see this is where the original
canisters were supposed to go in, and
then these were patched in.
It also contains a dirty sock in the
middle, they have to stop this little
hole somewhere.
I wanted to throw something.
So yes, with enough gaffer tape, you can
fix everything, even in space.
And then we get to space, huge life
support systems, they're basically the
same idea, except built in a compact
way. This is the backpack from an Apollo
moonwalking suit and you see here all
the components we had before.
There's an oxygen bottle that supplies
breathing air.
There's a CO2 scrubber that's sitting
here horizontally.
And then this power supply in some pumps
and at the top here is a
evaporation device to cool the
space you and you're in direct sunlight
on the Moon.
That's basically all there is to it.
The more modern designs
look kind of similar, this is a
Russian Orlan spacesuit that is nowadays
being used as this.
You flip open the back of it and you
climb in behind and then you open the
door of your cosmonaut colleague, opens
your closed the door behind
you and seals at you.
And here you can see as well there's an
oxygen bottle, there's a scrubber
container and so on that supplies oxygen
for eight, since it's only
only about 800.
You can carry it all around in your
spacesuit. And since you are in
weightlessness anyway, weight doesn't
matter.
Now, if you want something like this,
if you know, thinking, whoa, I want my
own spacesuit, I don't want to breathe
the air of the people around me, which is
very understandable in 2020.
You can actually buy these,
for example, scuba breathing systems
are commercially available.
They set you back about 7000 euros,
but you can just go to a diving
store and buy one of these.
And these work very much by the same
principle. You have a oxygen
bottle attached to the back and you have
a container with soda, lime and soda.
Lime is nothing else but potassium
hydroxide.
Mixed with some of the stuff, some days
to see when the Dakota has saturated
it and so on, but that's exactly what it
is for.
And I know some people from
the diving club of Aalto University shout
out to them for from here that own these
devices and they have actually been going
to the supermarket with a breathing
glue to shop for
groceries during the crisis.
So if you don't, for whatever reason,
want to breathe the same air as the
people around, you get
a scuba repeating device.
It might also be useful if later you
get to own a spaceship or something.
Right now,
now that we know how it works
in the basic form and in a space suit,
let's look at some actual life support
systems that are being used nowadays.
The SpaceX Dragon two, which is currently
attached to the International Space
Station, has a
pretty much run of the mill life support
system that we can now
understand. Here's a diagram from the
from the basics publication about that.
You can see the capsule, the pressure
vessel and basically at the bottom or
under the floor covers is where all
the magic happens.
There you have a bunch of things that we
can now identify here.
On both sides of it are these bottle.
They have two times three bottles
of these, actually only one.
The top bottle each is filled with
pure oxygen and the bottom two are filled
with a mixture of nitrogen and oxygen.
The idea with that is if the
capsule were to be evacuated, either
because somebody needs to climb out or
this leak that can be pressurized
with basic compressed
air from these two bottom bottles.
And then to refresh the air as
astronauts are breathing, they only need
one of these bottles each.
Also, during reentry, in order
to cool the system, they just about
cooling their open the valves and blow
air through it, which causes the capsule
so they don't have any need for a more
complicated cooling mechanism.
In addition to that, they have
these sort of lithium hydroxide
canisters that actually a commercial
model that apparently you can buy it for
submarine operations.
And these are a bit larger than the ones
we've seen before from the Apollo thing.
So this actually can be
left in place for one day or
four person crew and spacecraft.
And you can take them out and exchange
them. They have this replacement rack to
the site you.
If you're in the spacecraft and you look
down and you open the covers,
it looks something like this.
You see the bottles here on site and
then you see the active
lithium hydroxide canister for CO2
scrubbing there and then the three
replacement ones. Once a day, one of the
crew members open it and swap the
kind of stuff. But then you also have the
urine container and the waste container,
so maybe you don't want to put your hand
in there in space.
One funny feature
of this life support system is also the
toilet, which is part of this
sits on the ceiling.
So when you launch you, you're actually
sitting under the toilet of the
spacecraft. Of course, during launch,
it's probably unused it.
I'm not sure how trustworthy
this seems to the astronauts on reentry
window then suddenly sitting under the
toilet.
But apparently this works well.
I've heard no complaints about it.
All right. So another
real life life support system is
the so use cockpit, and
you may have seen something like this in
the movie gravity or something like that.
It's full of displays and buttons
and levers and so on.
But the user interface of the life
support system is actually completely
supplied by these three valves.
After two middle ones, which can
be used to regulate the oxygen
flow from the main and backup systems.
And then for the last stage of reentry
and also for emergency cases, the
valve left open see emergency
oxygen flow, and that's all there is.
The fans are always running
the CO2 scrubbers, all the scrubbing,
and you do not need more than this
as a user interface for your life support
system. So you don't need to worry that
much when you're in the Soyuz craft.
If after a night of drinking
with some Russians, you suddenly find
yourself waking up in a Soyuz craft.
You don't need to mess with many
controls. If you have too little oxygen,
you just turn this off.
That's.
So now we've been talking about all these
practical things that have been used in
spacecraft, but these are not really
reusable. I mean, we have oxygen bottles
when they're empty, they're empty.
We can't get new oxygen in space
and we have CO2 scrubbers.
And when they're saturated with CO2, then
therefore then you need to go back to
Earth.
So both the Soyuz spacecraft and the
Dragon two have very reasonable life
support systems for what they're built
for the flight to the ISIS, and then they
come back in 90 minutes if you want.
They don't need anything more fancy.
But for the space station itself or
anything more complex than that, you want
something reusable and how do you do
that?
There is a very practical, endless source
of oxygen available if you have
electrical power because you can simply
take water, H2O
and with electricity,
split it into hydrogen and oxygen.
On Earth, it's quite easier just to
electrodes, water at life, electric
current. You see the.
One side if you hydrogen or the other one
side gives the oxygen.
It's not that easy in
space because the
if you put an electrode into
water in zero gravity,
it forms the bubble around the electrode.
And then the electrode no longer touches
the water because the bubble doesn't go
with.
But you can do it, and I can show you in
a second how you do it.
First thing, though, you need to
have a good source of water
that you are not planning to use for
anything else, like drinking.
So what's a good source of water that you
do not want to drink anymore
on the ice?
They simply use the toilet.
Astronaut P gets recycled
into the oxygen system on the
ISS. The oxygen system looks like this,
so sometimes people ask if you are on the
International Space Station and you're
staying there for six months, do you have
to drink your own pee in space or
something like that?
And the answer can be a resounding no.
You don't need to drink your own pee.
You will breathe your own penis.
So.
How does this work, then you see these
two wrecks are the life support
water recycling system of the SS.
We have here a centrifuge where
the water gets boiled
and separated from salt and
any other more complicated components of
it. And then we have two more centrifuges
that are the electricity
system that actually takes the hydrogen
and the oxygen apart.
There are also other things like.
Filter system to get any other pollutants
out and then you need to regulate the
level and so on.
But in the end, pee goes in one side of
this device.
Oxygen comes off the other.
And since you have solar panels and
much more effective solar power and space
on Earth, you can produce
basically endless amounts
of oxygen by just splitting
up.
Which leaves you with the problem of CO2.
How do you do a reusable CO2
scrubbing?
And here nature gives us
some wonderful materials, for example,
activated charcoal.
If you have a surface of activated
charcoal, actually let air continue
to run over it.
CO2 molecules like to attach to
the surface.
But only one molecular layer.
There are others that are working even
better than charcoal, for example, there
are some zeolites and some amines that
useful that not going into too much
detail at you.
So you let it run over and it
touches on the CO2 molecule
stick to the surface. And after about one
hour, the shockable filter is full.
No more CO2 attaches to it.
What you can then do is you
close the valve to your spacecraft and
open the valve on the other side and open
this surface to the vacuum of space
and you heat it up a little and
evaporates off to space.
And then you've got a clean piece of
charcoal again.
That's exactly what this device does on
the International Space Station.
This is the so-called carbon dioxide
removal assembly, and it has these fancy
violet connectors.
I like the design of this very much.
It has some zeolite
absorption bits by the cabin
egg it's run into.
And then after an hour or so when
it's full, it gets closed off and open
to the vacuum of space.
And because then it's half the time
up and half the time closed, there are
actually two systems that are alternating
between open and closed state.
Here at the bottom, you see these two
openings where it then attaches out to
the other side of the spacecraft, and
that leads off to the vacuum of space.
This method is called pressure swing
adsorption because you are swinging
between inner pressure and pressure
outside.
Now, if you have your CO2 removed,
you can just vent it out, and that's
mostly what is being done in
International Space Station, but there is
another helpful chemical reaction
that makes even more sense to
do after.
We have CO2 and we're just separated it
using our precious wing mechanism.
And we also didn't have the hydrogen left
from splitting our water.
I mean, we split the water and we're
breathing the oxygen. What do we do with
the hydrogen?
If these two are put together,
they can chemically react to methane
and water.
Isn't that nice because we have something
that we don't want and something that is
no use for us and we get something
at least part of it.
All that is food again, water
as an input in order to do this.
Unfortunately, it requires pretty high
temperatures, so you need to heat these
up to 300 tubes and you need to do
it under high pressure so that the
molecules actually react with another.
You also need two catalysts.
Nickel is quite normal for this.
Ruthenium is more efficient, but much
more expensive. So that's what's used in
space because money doesn't matter.
And then you need to
first compress it to that and expand
it again for use in the space station.
But the advantage of this is from the
original water that you put into the
splitting. You have four
water molecules that went in.
You still recover two of them back.
So you are getting half of your water
recovered in these cycles.
This is what the device looks like on the
International Space Station, and it has
lots and lots of troops and complicated
mechanisms. Because it contains
decompression stage, it needs to
mix the input gases, needs to separate
the output gases and then expanded to.
So it's installed right next to
the carbon dioxide removal assembly.
The second output have methane
at the moment is just dumped overboard
from the International Space Station, but
in principle, this one can also still be
used for something useful.
It can be used as a rocket fuel space.
This new rockets run with this,
or it can be heated and
electrically decayed to
decompose to carbon and hydrogen
again. Then you have the hydrogen used
reusable.
The problem with this is that you need to
basically put this in a steel tube and
heated 2000 degrees, and then you have
the carbon starting to lay on your steel.
So this is not something you want in the
space station right now, and this is
not something that's overly, overly
practical, but it's
a possibility for the future, maybe on a
Mars. You can do this to get
carbon for also for
of virtualization of sorts.
So let's plug it all together.
This is life support system looks
like this. This is the American life
support system in its original design
when the ISIS was launched in 1998.
You still see here is a fancy tube screen
that was used for computer controlling
it and so on.
This is also still the design that
was supposed to include a shower kit in
the shower never actually made it to the
space station due to weight restrictions.
But this the toilet.
Then there's the water processing
assembly, the O'Toole generation,
the carbon dioxide removal and all that.
So it's not small,
but it's also not too big, given that
it's mostly
regenerative as
a diagram.
It looks like this.
It has all the parts we never talked
about. It generates oxygen by
splitting water, it
removes CO2 from the air,
and then part of the CO2 is still
vented overboard and part is fed
Sabatier system.
Also, part of the hydrogen is vented
overboard and part is fed into the system
and then the methane gets into global.
Noteworthy here is there
are only two inputs.
This one is nitrogen, which
is just used to regulate the atmospheric
pressure. That's actually a very small
amount. Basically, you only need to
contract some leaks in your station.
Not much.
And the other one is only water.
So the only thing you need in the ice is
to keep people alive is water
and electricity.
How much water?
I found some conflicting reports.
I look to is a status report
of the last couple of years.
One thing I found from 2010 was
talking about the entire station using a
seven and a half liters of water per day,
which is not that much.
But then, with newly updated systems, a
more recent report was talking about only
a little bit of a one liter of water per
day. And that would be quite amazing
because that's a tiny amount to
supply all the tremendous.
Yet there's still a venting of bullet,
and especially it's it's kind of
unsatisfying that this carbon atom.
I mean, it came into the human body as
food and we breathe that out CO2 and then
be vented overboard.
Wouldn't it be nice if there was somebody
who would like to make use of
the carbon? Wouldn't it be great if
something produced the carbon from CO2?
And indeed, there
is. I mean, we humans turn
oxygen to CO2 through respiration
and the other way around plants and
other marine life forms, for example,
cyanobacteria and some
other micro-organisms.
So in CO2, back into oxygen through
photosynthesis.
And experiments have shown that many
plants do just fine in space without
gravity. There's a picture of salad
growing on the SS as they grow these on.
Not actually in soil, but in some growth
pillows that contain nutrients.
And then you put the seed in and a little
bit of water and the gold
in general, plants that want to grow
upwards and want to form stalks or grow
away from gravity have a bit of problems
in zero gravity because they don't know
where to grow. And then they get weird
shapes and sometimes don't properly work.
But if you have something like this,
which is just a cell, it just wants to be
a leaf.
It grows just fine.
So the question is, why not just stuff
your space plant roof full of plants and
see if that works as a life support
system? This is not just a good idea
to support you to get your CO2
away and supply you with oxygen.
It's also such that
plants are psychologically
been shown to be a big comfort factor.
I mean, if you are
living in a gray box office spacecraft
all the time, it's actually very nice to
be able to tend to a little flower now
and then maybe even talk to it if you're
starting to go crazy.
Well, before you started to go crazy,
this picture here shows the first flower
that has ever bloomed outside the Earth.
That's Xenia.
That was the video zero one experiment
on the Earth. You see the same plant
pillows being used.
So this begs the question how much green
stuff does one human
actually require for its life
support and.
Basically, all spacefaring nations have
done some experiments about that,
the Russians were the first ones they set
this up.
The Bio's facilities
by history, especially since 1972.
This is an underground steel and closed.
Well, the laboratory in the wonderful
city of Krasnoyarsk in Siberia,
where people have
been living since 1972
in continuous experiments,
they have successfully had people in
complete isolation.
So the system was shut off only
electricity, electric power going in
for 180 days and they
were eating the food that they were
growing and the plants were supplying
their oxygen worked fine.
Their research showed that you need about
eight square meters of plant growth area
to supply sufficient oxygen for one
person, which is not as big as you might
think. Of course, they chose plants
to be ideal yields, especially
there are small growing varieties of
wheat, super wheat and
dwarf wheat that grow very quickly
and produce lots of biomass.
So eight square meters, they found, is
sufficient to supply oxygen for one
person.
They also found that it's not sufficient
to supply food for one person, and
their calculations came two that you need
about 11 square meters to supply
food for one person.
Yet they supplemented protein
and some additional meat products and so
on from from
their stores.
So they did not just only eat
the stuff they
grew their.
The Chinese space agency
and China is very keen on going to the
Moon. They also have a very similar
experiment running since 2014.
The Moon Palace, one in Beijing looks
like this. It has two growing
chambers and one living chamber, and
three people have successfully lived in
there in isolation.
For the longest I found was one hundred
and five days, and the difference to the
Russian system is it's a more
modern form of of
enclosed
farming. They are using vertical farms
stacked in multiple layers with LED
lighting, so it's more energy efficient.
And then they are also recycling
the human waste as fertilizer,
and they are growing their own animal
protein by having mealworms.
And there was a very funny part of the
the article that they had invited Western
astronauts to participate in the study,
but they refused due to the idea of
eating mealworms as their primary diet.
But apparently mealworms.
They get about finger sized and they
are 75 percent protein and quite
practical on close ecosystems like.
Then the Americans always keen to overdo
things, also had a
experiment for enclosed ecosystems
called the Biosphere two.
In the end of the 80s, a billionaire
decided that he wants to do the biggest
and best ever biosphere
project like this and invested
enormous amounts of money building this
in the desert without consulting
scientists. Too much, though.
And it turned out not
so well.
The first experiment was unsuccessful
because, as it turned out,
if you put a greenhouse full
of plants, you have trees.
Here you'll see wood, which is
not me or just brown, who does not
photosynthesis. So a lot of the biomass
they put in was actually not doing
anything. They also had two parts
simulating desert. And as it turns out,
the cactus is not a good source for
photosynthesis. If you want to live off
it,
then they also wanted to make it look
like nature. So they built all
these stone structures out of concrete,
and they used the same kind of concrete
that, for example, Disneyland uses to
build artificial mountains and so on.
The problem is when concrete is freshly
set and curing it is absorbing
CO2 from the air because of the reactions
that are going on in the computer room.
So what happened there is that the
concrete absorbed all the CO2 from the
air, which was fine at first.
But then the oxygen, like
the plant stopped doing photosynthesis
because there was no CO2 for them to work
with. And then the oxygen gets dropped
and they had to resupply multiple times
oxygen from the outside because it did
not really work.
There are nowadays other and less
overdone closed ecosystem
research facilities.
One in Utah, one at the Johnson space is
Houston, and they are on smaller scales,
producing very successfully
enclosed by a life
support system. Results.
But this one was a quite famous
and quite unsuccessful one.
In spacecraft so far,
there has not been the attempt to supply
large amounts, the major amount
of life support to plants
there are, though, some experiments on
the Earth, apart from the plants that
we've seen earlier that have mostly
grown to test plant growing, per say,
there's now a so-called photo
bioreactor running the ices.
This is the wreck of the European life
support system that
works in a similar system as the one
described before.
And on its CO2 output lines
enriched to CO2 enriched air
gets fit into these boxes here on
the site. And in these boxes,
there are other microscopic
chloride bodies
in the water solution, and they are being
supplied to the CO2 rich air and
light, and they
turn it into oxygen and they also produce
edible biomass.
This very same alga is used, for example,
in Japanese cuisine as a seasoning, so
you can use it or you can
drink it as a protein. Shake me
inside these boxes.
This reactor looks like this.
You have a bit of a problem if you want
to bubble CO2 to
a solution in zero gravity
because bubbles don't rise.
So this system is pumping
the air and water mixed
around through this lighting source
all the time. And that way, the
water by erector produces oxygen,
so that works well.
Here's another picture of another
astronaut just
taking out the bottle where the other
solution is stored so you can.
After a while when the I have grown big
enough to take this out, you put some of
it or maybe drink it, maybe
bring it home to Earth for analysis and
fill in your water and some nutrients
and put it back in to continue
operations.
But as soon as you saw this is just a
small device, this is maybe 10
centimeters by 10 centimeters.
This is not enough to supply even a
single human.
We've seen you need maybe eight square
meters of front.
It's a it's a test, but
since it seems to be running well, that's
something that can probably be scaled up
to run the entire spacecraft
life support systems.
The second one that's been on the.
ISIS, that's also very interesting.
This is an even smaller one, so this is
we can see the comparison to the fingers
has been using cyanobacteria.
And if you go to the supermarket
and buy spirulina tablets, it was all
like dietary additions, green
bean tablets that contain
protein. This is exactly the same
cyanobacteria that they use in that.
And this also manages to produce
oxygen quite successfully.
And I'm thinking this specifically
because this website about a
guy who just did this at home,
he took some, some
clear bottles, put
these cyanobacteria and water in there
and produces on oxygen that way.
So if you have a hackerspace and want to
run it like a spaceship, you can
think of just doing that.
You take some maybe clear glass
or plastic tubes, fill them with water,
put these cyanobacteria in and you
produce your own oxygen and get rid of
CO2.
So again, another hint for the year 2020.
If you don't want to breathe other
people's air, this is a very practical
way to do it, and this can be basically
done with hotspot material.
Then.
One thing to think of if you have
an enclosed ecosystem, even if you have
perfect CO2 removal and oxygen
replenishment, you are still
in a closed box and you're still
breathing the same air over and over
again. Whatever other gases
you produce, and I'm not specifically
talking about gases coming from your
butts, but I'm also talking about those
even small concentrations will accumulate
over time. So if you are not taking care
of them, your spacecraft will get
smelly and might also get in
other ways, problematic.
One example was a plant growth
experiment on the Russian space station
Mir. They were trying to grow wheat
just to see how well it goes in zero
gravity. It was a continuation
of this Russian Bio's experiment,
trying to run it in the middle and
everything drew well.
They even got large amounts of results.
This is from the research paper.
They found that everything
grew even better than on Earth.
And when they returned the seeds to
Earth, they found that all of them were
sterile.
And I didn't quite understand why.
I mean, there was no obvious DNA damage
from radiation or anything, and there was
also no obvious reason why Zero-Gravity
would make me see
it sterile.
And then they did a bunch of experiments,
and after many years, they published this
paper and found that actually
ethylene gas was trapped
in the space station and that didn't do
anything to remove it.
And ethylene gas is a plant hormone.
You probably know it's from the
supermarket bananas.
If you have a
supermarket, you can always buy fresh
yellow bananas.
But they're being harvested on the other
side of the planet. So how does that
work?
You ship them while they're green and
then you give them ethylene gas.
And that's a hormone for the bananas to
turn yellow and ripe and has
lots of different effects on different
plants. And as it happens in the
concentration that they had here, it made
the weeds grow.
Sterile, so this doesn't work.
So you have to take into account what are
used to trace gas concentrations
as you grow plants in space.
And this actually also leads to the
interesting question if plant hormones,
gases, plant hormones have some strong
effects in wheat.
How is it with humans?
I mean, so far, we've always
had astronauts under very controlled
conditions in space stations for a long
time.
But what is in control in commercial
space flight coming up?
You will suddenly have, let's say,
teenagers flying in a spacecraft to
do their hormones suddenly accumulate.
Does it cause psychological problems?
This is nothing that's been researched
yet, but I find the idea very interesting
that maybe there are
biological messengers that we actually
are unaware of that are very much
concentrated then causing some
issues in the future.
Another thing that is a problem
in space stations is smells,
not just smells produced by humans, but
also molds.
Here's a picture from the International
Space Station.
It's on the in the Russian, I think the
space, the module where the astronauts
typically hang their towels to dry off
the workout.
And as you can see, there's a nasty
looking black patch of mold growing
there.
I'm not quite sure which mode this one
is, but there have been samples from
different parts of the ISS brought to
Earth and analyzed, and I found that
Aspergillus nigar, for example, that's
the common black food.
The girl was very nicely on the ISS
and there were ideas. Maybe this needs to
be sterilized. Maybe we just go around
with a big UV light lamp because UV light
tends to kill fungal spores.
But as it turns out, Aspergillus
kneecapped produces melanin,
which is just the same brown
color, and that's also in skin and hair
and so on. And it produces so much of it
that it's basically resistant to UV
radiation, so we can't kill it like that.
You also can't kill it by shutting
all of the doors and evacuating
the air, because as it turns out, it has
spores that survive vacuum.
So it looks like you will not
get rid of mold in the spacecraft
anytime soon. At the moment, they're just
scrubbing the surfaces with alcohol now
and then. And that way, trying to keep
it in check on the space
station Mir.
There was in the end of its lifetime the
problem that actually mold was growing
through insulation foam layers on the
walls of the space station.
And the smell got so bad that astronaut
cosmonauts apparently developed
a so-called second space sickness.
The first one, their normal space
sickness you get when you fly to space
and you get weightlessness
and some people throw up.
And then there was the second from one of
our astronauts returned into the
space station from, for example, a
spacewalk where they had seen spacesuit.
And then they went to the space station
and it smelled so bad that they got
physically sick from it.
Likewise, there are stories of Soyuz
spacecraft landing in Kazakhstan and
the people that open these space capsules
for the first time, they have problems
that the astronauts brought
with them the ugly smell of space.
So spacecraft tend to be
quite smelly. It's it's how
do you get rid of that?
Well, one way, of course, is plants help
with this. If you have lots of plants,
they make you ask me a and they they feel
that they are especially the sort of
plants that have air roots.
They just make the
room atmosphere better.
This is, in this case, literally
the way they do it.
But you can, of course, also use chemical
methods for if you heat your air to 500
degrees, it destroys most
organic molecules.
They just simply do produce and fall
apart or burn
with suitable catalysts.
You can also make this
more efficient. You can also make
it destroy ammonia because
ammonia is a compound
that forms in your sweat.
And if ammonia accumulates too
much, it starts to attack plastic and
parts of the life support system, so you
want to get rid of ammonia
and sulfur and so on.
So lead still,
keep your air up, run it over a catalyst
and just keep cycling through it.
And that keeps the
trace contaminants on the ISIS control.
Activated charcoal filters also work well
to get more more complex molecules
out of the air. All of these are running
the analysis. The problem with this is
that they are still quite bulky.
If you have a small spacecraft, you just
want in a small capsule to return to
Earth, you normally don't have
these and these tend to get smelly.
So if you
are thinking in terms of science fiction
and and nice and fancy stuff that we
might be aware, most of this
spacecraft you see in such a cheap,
probably very smart.
Right, and that brings us to the
conclusion.
Life support systems have developed lots
and they are
practically surviving in space, and
they are not too bulky, but also not too
small.
It's almost time for completely closed
systems. We're still venting a bit of the
International Space Station into space
all the time, but with enough plants in
the roof, it's probably going to be seen
such that you are in a completely
enclosed, distant way when you need to
put electricity
by a regenerative systems are not just
important in space, you can also help
them at home and live nicely with
them.
So if you run your hackerspace like a
spaceship, maybe start building one
yourself. It's not that complicated.
If you want to learn more, I've published
a book about all this and even more.
There's also a German version if you
Google for it, it's
available in the typical places where you
find books.
So I am very much looking forward to the
questions and hope you learned something
for your life in space.
Yeah.
Blown
pretty amazing talk.
One thing, maybe that we want to fix
right away, we're still having some
audio issues and I'm very sorry about
that to the stream we luckily
did.
Back up, recording locally at
all this place, like, like we said
earlier, he's like
in the depths of Finland, somewhere
in the little hut and in connection
is not that great.
What's amazing is working as a this
was, if you could,
in there in the share that
we have this webcam share a small
icon on the bottom.
If you click on, that will
turn off your video.
And we are hoping that even though we
cannot see it anymore, that maybe the
audio now has a better bent with a
friend. At least, yeah, we
can hear you better.
Yeah, let's try it like this, see if this
works. OK, so
our lovely signal angel has collected
a bunch of questions and the chat was
super on fire.
Like I
actually had the IFC channel
open all the time and I saw messages,
scrolling feeds, so shout out to each
other.
Yeah, I think this was like
the worst shift ever for a signal
angel.
So much to do, but there are
a few questions.
So let's go through them.
First question was Wait, can you brief
just 100 percent oxygen
at 0.2 bar?
Yes, that works, this is how it's usually
done in space suits in order to reduce
their bulkiness, you just reduce the
pressure.
The problem is not breathing
100 percent oxygen, that 0.2 power.
The problem is getting there because
if you start from a normal environment
like sea level environment, you just.
Depressurize, you still have your blood
were born because you have lots of gases
dissolved in your tissue, in your blood
insulin, you need to really slowly
go down with your pressure.
Otherwise you are.
Your nitrogen is going to form bubbles
in your in your tissue and tear your body
apart.
So what they typically do on the
International Space Station is they go
to the airlock a couple of hours before a
spacewalk and start to
lower the price. I'd read you in
the past, what they used to do was
camp out.
So overnight they were already the night
before sleeping in the airlock and then
the next morning they went out.
Nowadays, they found a more efficient
method as they put on this spacesuit with
normal pressure,
start filling it with oxygen slowly and
reducing the pressure, and then sit on
the cycle ergometer and to cycle cycle
cycles because that pumps the air or the
nitrogen out of your system.
So it's a similar problem.
If you are diving and you are 50
meters depth and you suddenly come to the
surface, you would die because
of the compressed nitrogen expanse.
And that causes problems.
But apart from that, yes, you can easily
survive in 100 per cent oxygen atmosphere
as long as the pressure is low enough
that it doesn't get toxic.
Yeah, it's like when diving,
you know, normal atmosphere is sort of
space and diving as
your spaceship and you need
to slowly depressurize.
Next question regarding oxygen candles
if this thing burns through at least
oxygen, doesn't that need oxygen for
the burning process?
Again, I think there's maybe
a slight misnomer here,
and not really.
I mean, I can probably go back to
the slides wherever it was.
They don't need oxygen
for burning because it's a redox
reaction. I mean, you have
the potassium chloride sort of
chloride coming in, and
I reported that reacts with and it simply
passes one oxygen from this one
to the ihren. So the oxygen ends up here
red objects and just reduces
and oxidized at the same point.
So it brings its own oxygen along and it
actually has oxygen to spare.
That's why these produce oxygen stable.
Mm-Hmm.
Interesting. Yeah, something for the
chemistry nerds there.
So these slides will, of course, be up in
the recording and you can go through the
equations, probably and
found that out herself.
Is there any advantage to using either
sodium chloride or lithium
chloride?
The advantage of sodium chloride is that
it's just dirt cheap.
It's really just table salt that
you can get from anywhere and then you
just need to have the reactions
to get the oxygen on there.
In compressed lithium flow rate is
more of a problem.
It's more expensive, and B lithium
salts in general have psychological
effects if they get out.
If you have any dust coming out, defense
holes have been used for a long time
to try to cure depression.
So you don't want too much of that flying
around in the space station.
The advantage of lithium, on the other
hand, is that it's much lighter and
weight is almost a premium in space.
So it's a trade off
and the Russians have decided to go with
sodium, whereas the Americans have
decided to go with lithium.
So that's both.
Cool.
And that's the question, I think,
to the equation where,
you know, inputs of some Nessus and
output of some muscles.
And the question was
so the additional carbon that's
essentially coming from the food sources.
Could this be recycled and plant
materials?
Yes, I mean, that's basically what the
second half of my talk was about.
I mean, I saw the Christian scrolling by
as I was still talking about their
methods in the beginning.
That's exactly the point you have to
carbon coming from the food, going
through your system, being trained to do
so too. And then the plants do the
opposite and turn it back into their
sugar so that they continue to head
south. So that's where the idea comes
from to use plants as life support
systems.
Yeah, pretty much like a circle of life
inside a spaceship, essentially.
Yeah, I was I was thinking in the
beginning, should I draw this such that
these errors actually go around?
But then I thought, it's a bit disgusting
to just throw an arrow from the brain
back to the what?
Well, it seems to me like there's
lots of pretty disgusting smells
and everything, so people might
not have been shocked that that much.
When I was actually talking to
a Swedish astronaut a couple
of weeks back, he was giving a
seminar in Helsinki, and I ask him this
Did he have the feeling it was actually
working on the outside of the
International Space Station installing
one of these solar panels?
Did he have the feeling that it got
smelly in his spacesuit?
And he said that you were so busy doing
everything that you didn't notice?
But some of his colleagues remarked about
the smell all the time in the space
station. And apparently when
you look at web streams of astronauts
returning to the space station when
they've been there before and then come
back, it's always the first thing they
say. When they enter the space station,
they remark on this man are the Iceman.
It's apparently very characteristic
smell.
Wow. Yeah.
Sadly, most of us will not be able to
experience it, but apparently
it's legendary.
So let's leave it at that
again. Next question When scaling
up from space stations to bigger habitats
like Mars colonies or even O'Neale
cylinders, does something fundamental
changed about what to consider and
how to build life support systems?
Well, there's already some questions that
need to be addressed in scaling up from
what we have now.
Like we have, for example, the
The Dragon capsule that just wants to fly
for three days, go to the east, go
back to Earth. That's it.
So there you don't need to consider much.
You just built a scrubber and you have
oxygen bottles and you've got, of course,
this still needs to be reliable and work
very well about that's that's
where we are right now.
The International Space Station is
almost completely reusable
in terms of its life support system.
But the problem with that is it's still
designed as an experiment platform.
The system fails from time to time, and
then they had problems that they need to
change to the Russian system instead of
the American. Because something breaks
here, something fix that.
One thing that you really definitely want
if you fly to Mars or if you have
colonies, you want the system to be fail
safe, you need to build it tested.
It's serviceable. You need to build it
such that it is redundant
enough and that it
well, ideally that it cannot break down.
And that is one additional advantage of
plants because plants don't break down.
If one dies, the next one goes in its
place as long as you don't poison
their whole life support system
altogether.
You'll be able to just scale about by
just giving it more place to grow.
So these systems, if you want
to have more like you growing or you need
to put an additional bottle there,
put some lights up and you can grow more
of it.
So that is something that
is an active development because people
want to fly to Mars pretty soon.
I mean, you know, Musk keeps talking
about it in the next five years.
But nobody has proven yet that there
is a life support system that is reliable
enough to actually get you there.
You don't want to strand halfway with the
non-working life support system.
And then as soon as you are on a planet
and as soon as you can plant stuff in
the ground, then there's no reason not to
just go for bananas with growing
plants literally full bananas.
I suppose there have been experiments
with strawberries
growing in lunar soil.
As long as you give them water and a
little bit of nitrogen that they grow
in lunar soil just fine.
Then you have Martian dust
equivalent studies of people trying to
grow stuff on Martian soil,
and that apparently is also something
that is possible.
So then you just need to go there and
start growing things.
And as soon as you have an ecosystem
like like the closest ecosystems that
we've seen on Earth, we have eight square
meters per person. You can just scale up
by getting eight more square meters per
second person.
As soon as you have a life
support system where you have eight
square meters of plants growing for one
person, you can just scale it
up by adding another eight square
meters and you have capacity for a
second person.
Mm hmm.
Premeditated brings us to the to the
next.
Question.
Yeah, I think maybe you've answered
this already.
I'll just read it out.
Why is the entire system set up in one
place seems to be super dangerous, single
point of failure?
Why not have multiple smaller systems so
lots of one could be compensated by
sealing off a part of the station?
And yeah, I think that's essentially what
you just said right now.
Well, on the access, there is
the big system that I've showed.
That's the American system in the
military that does most
of the work for the station.
But the Russian part of the station
also has a system that works
in pretty much the same way.
It's not quite as redundant.
So if anything were to happen, you could
seal off the American pot and run with
the Russian system.
Since the last five years,
there's also the European advanced
closed loop system that has the
bioreactor attached, and that's in the
Columbus module. So that's again on the
other end of the station.
So right now, there are three redundant
life support systems running on the space
station.
Of course, the advantage of having it all
in one place and together is
that you can more easily feed stuff from
one system to the other.
If you want, for example, your water to
come from your toilet into your water
recycling system, and from there you want
the hydrogen and the oxygen to go further
into other systems.
So it's always a design question
how much redundancy and fail safety do
you want and how much compactness of the
system do you want?
I suppose it's similar
like any other.
Yeah, the audio is again breaking up a
lot.
I think I will
pick one last question here and
then we'll wrap it up.
Also, time starting to run out.
So last question
that I'll pick
so someone would like to know if due
to the growth of surface and square
and the volume in Cuba, it gets easier
or harder to create and maintain the
life support system on spacecraft.
Some.
Well, interesting
question.
So in general, as
as.
There are more people you just need
more life support system, a bigger
system, or you just build more smaller
ones. So that should not be
fundamentally a problem.
You just need more of them.
I would assume that the bigger systems
in general have high efficiency because
you can just devote more
space to smaller things to
do more little cleaning assemblies
and so on.
But then on the other hand, you need more
redundancy as well.
So that's actually a very good question.
Then there's also one thing now that I
still have to slide up here, the numbers
I have here oxygen, food and water
requirement, these are given by Nassau
for the standard crew member.
So that is for one human male.
Nassau always calculates this in terms
of human males.
On average, female crew members
have lower metabolic rates,
so they use less calories.
They also use less oxygen and
less water proportionately.
So actually, it makes no sense
that muscles since a majority of male
astronauts into space, all the other
space agencies as well because women
simply consume less resources
from their life support system
perspective. So if you wanted
to make an argument, why you should a
crew of women to Mars, this is your
argument here. They would use less
like support resources.
Yeah. Well, yeah, that's a pretty big
advantage right there, like you can't
argue with with that, you know?
Cool. So I think
we will wrap it up here.
I see that you're also active in the IOC
trend, so if you have any more questions,
feel free to hit up the IOC trip.
Maybe you can stick around a little bit
and answer some more questions there.
I'll also be walking around the
world in the cases where it works.
Yeah, great. So if you catch us, if
you catch or somewhere there hit them up
about the audio issues, I'm very sorry
again. We do have some back
up recording. Probably we'll take a look
at that and see if we can fix the audio.
So hopefully in the final release
that we will make to media CCC,
the E the audio will
be a little bit better again.
Sorry,
but yeah. Well, thank
you very much.
I'm very honored that we were able
to show like the first
part of the trilogy about Epic Space
Adventure and what they need to do to
make that happen on our
stage.
Thank you a lot.
And.
I hope we'll have a great
I'll see free for the rest of the day.