The Martian atmosphere is ninety five percent carbon dioxide, about a few percent nitrogen,
a few percent argon, trace amounts of everything else. But there’s still a lot of CO2, and
so that’s probably the most abundant resource on Mars other than dirt. CO2 has oxygen bound
in it. And if we can liberate that oxygen from some of that CO2, then we can use it
to do something useful. The goal is to pave the way for future human exploration of Mars
by demonstrating the ability to generate oxygen. That's where the magic happens is inside that
box. NASA is set to launch its next rover to the red planet in 2020. Stacked inside
are seven science instruments, six of which are focused on sample analysis like this SuperCam
and a spectrometer called PIXL that’ll measure chemical signatures inside Martian rocks.
And this box getting lowered inside the belly of the rover is MOXIE, or the Mars Oxygen
In-Situ Resource Utilization Experiment. It’s got an agenda separate from the others, and
that’s to make oxygen on Mars for the first time. Well, at least in real life. In the
Martian, there was something that was called the oxygenator. If the oxygenator breaks,
I’ll suffocate. If the water reclaimer breaks, I’ll die of thirst. So we jokingly refer
to MOXIE as the oxygenator. It's unclear in the movie what technology the oxygenator is
actually using, but it's very likely that it would be something like MOXIE but scaled
up. MOXIE uses a technology called solid oxide electrolysis. It works a lot like a reverse
fuel cell where instead of putting in a fuel and getting electricity out, we can put electricity
in and electrolytes and basically get a fuel and an oxidizer out. On the outside the rover,
we have a small box with a filter. The filter is to make sure that we don't draw in any
dust from the Martian atmosphere into our system, because the next thing in the path
is a scroll compressor. The scroll compressor takes this low pressure Martian gas from the
atmosphere and compresses it and brings it up to something closer to Earth's atmospheric
pressure. Because the next thing that we do is we run it into this thing. We call this
our solid oxide electrolysis stack and it is basically a layer cake of a bunch of metal
plates, which are the dark green things. And then these light colored layers are thin ceramic
cells that have particular chemical properties where at high temperature, they can conduct
electricity using oxygen as the charged carrier. We heat this guy up to about eight hundred
degrees Celsius. You have oxygen ions on one side and you apply a voltage, then you can
selectively dry the oxygen through the ceramic membrane and separate it out from whatever's
on the other side. It goes through a set of sensors very much like these sitting here
on the table in front of me. And we measure what fraction of CO2 is there. We put CO2
in here. Oxygen comes out here. And the waste product, which is a mixture of CO and carbon
monoxide and unreacted CO2 comes out here. It’s gold because we were concerned that
MOXIE itself would run hotter than everything else around it. And we wanted to make sure
we didn’t impact any of the nearby electronics boxes inside the rover. And so, gold has very
low emissivity, so it doesn’t radiate heat effectively. This particular chemistry process
is sort of unique to Mars in its applicability, and also the packaging and how we actually
build this system to survive launch and get to Mars. No one has ever done anything like
this. MOXIE is going to make about six grams per hour of oxygen. It's not very much. It's
about enough to keep a small dog alive. We don't have the resources available on the
rover to run MOXIE for long periods of time continuously because a lot of the rover energy
has to be used for other science that they want to do. We will probably run MOXIE at
roughly once every two months. The goal for us is to sample different environmental conditions
on Mars. So day versus night, summer versus winter, dust storm versus not dust storm...to
assess how the technology behaves in response to these changing environmental conditions.
What might happen in the future really depends on the technology that NASA decides to go
with on Mars. If you're assumption is that you only have the CO2 in the atmosphere available,
then you'd have something like MOXIE scaled up by about a factor of two hundred. You'd
launch it and deliver it to Mars about two years before humans set foot there. It would
have a bunch of supporting equipment like a power system and a storage system, and it
would sit for two years and just generate oxygen and collect it, and then it would be
ready for use by the humans when they show up two years later. It's really exciting for
me to be able to build something that's going to land on another planet. I hope that it's
gonna work the way we expect it to. And that paves the way for future human exploration
in the not too distant future.