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Science Instrument of Mars 2020 Perseverance Rover

MOXIE of the Mars 2020 Perseverance Rover – part 3

The Perseverance Mars Rover‘s MOXIE runs the oxygen-making experiments autonomously and there are two challenges it is facing.

The first challenge is from the harsh Martian environment. The temperature can fluctuate for over 65 Celsius or 150 Fahrenheit during day and night, and it is yet to find out how the Perseverance Mars Rover‘s MOXIE will react to this abrupt temperature change. Moreover, in every Winter, around 30% of the Martian atmosphere vanishes and the temperature is so low that carbon dioxide solidifies and drops to the Martian surface. Ideally, the Perseverance Mars Rover‘s MOXIE should be able to operate at all times without stopping since it is designed to produce oxygen for human survival. Therefore, the record for how the Perseverance Mars Rover‘s MOXIE will respond to Mars’ harsh environmental condition will be extremely valuable data for MOXIE’s developers and researchers, so that the future MOXIE can be designed to work smoothly no matter the environmental changes. The Perseverance Mars Rover‘s MOXIE is planned to run 10 times totally during the mission under as many different conditions as possible. Our 1:2 Mars Rover Replica may or may not replicate the MOXIE instrument. If we do replicate it, it will not be able to make oxygen, and will not produce that much heat. But we may design it so that it will make the motor running sound effects.

If you are interested in our 1:2 Mars Rover Replic, you may check [1:2 Perseverance Mars Rover Replica Design and Building Diary].

The second challenge the Perseverance Mars Rover‘s MOXIE instrument faces is the byproduct generated. Theoretically, the carbon dioxide will be split into oxygen and carbon monoxide. However, scientists are still researching how to properly run the Perseverance Mars Rover‘s MOXIE instrument. If operating it too gently, the carbon dioxide will just go through the instrument and not produce enough oxygen so the oxygen conversion rate will be very low. But if operating it too heavily, not only will you get carbon monoxide, but also there will be some single carbon atoms. For now, the unwanted solid carbon is cleaned manually to avoid it from blocking the normal operation.

In the future, if humans can set foot on Mars, a much larger version of the Perseverance Mars Rover‘s MOXIE will need to make around 30,000 kg, or 66,000 lbs of oxygen to support a trip home from Mars to Earth. If the Perseverance Mars Rover‘s MOXIE is successful, this means it will save 4 to 5 trips from Earth to Mars for transferring that much liquid oxygen.

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Science Instrument of Mars 2020 Perseverance Rover

MOXIE of the Mars 2020 Perseverance Rover – part 2

Even though the Mars 2020 Perseverance Rover itself cost around 2.7 billion dollars to build, the value MOXIE will produce and the experiences that will be gained are far more than that. As mentioned before, the Mars 2020 Perseverance Rover‘s MOXIE’s goal is not only to make oxygen for humans to breathe but also potentially to help with burning rocket fuel. This ensures that astronauts can come back to Earth from Mars (if human exploration on Mars becomes possible one day). Oxygen tanks are always the heaviest items on a spacecraft. If the Mars 2020 Perseverance Rover‘s MOXIE is successful and scientists can see that in the future more and larger MOXIE instruments will make enough oxygen on Mars and store it into tanks, it will save countless resources and money for space missions.

The Mars 2020 Perseverance Rover‘s MOXIE can produce oxygen at a rate of up to 10 g/h. To make it more realizable for us, this can support a puppy to live. But for humans, we will need the rate to go up to 20 to 30 g/h. For the time being, it only runs for one hour each time as instructed. The Mars 2020 Perseverance Rover‘s MOXIE is only a prototype to run trial tests to make oxygen. In the future, around 20 years from now, a full-size MOXIE is expected to be built for Mars human exploration missions, and the oxygen rate will be needed is around 2000 to 3000 g/h, which is about 200 times more than the MOXIE on Mars 2020 Perseverance Rover can so now. Even though MOXIE now cannot produce a big amount of oxygen due to lack of sufficient space and power, nor can it store the oxygen produced, needless to say, this is a necessary start.

There are three main components for the Mars 2020 Perseverance Rover‘s MOXIE: sensor panel assembly, scroll compressor, and the SOXE(Solid Oxide Electrolyzer) assembly. MOXIE will collect carbon dioxide from the Martian atmosphere and then get rid of the unwanted particles by a filter. We might or might not make the MOXIE replica for our 1:2 Perseverance Mars Rover

Since the Martian atmosphere is around 170 times thinner compared to Earth, if letting the air at ambient pressure enter the reactive core, it won’t make enough oxygen. Therefore, the Mars 2020 Perseverance Rover‘s MOXIE will need to compress the air by itself in order to have a high carbon dioxide density. The compressor will compress the filtered air to a pressure level similar to Earth’s pressure. Then a process called electrolysis will split the carbon dioxide into oxygen and carbon monoxide by heat and electricity at 800 Celsius, or 1472 Fahrenheit. At the same time, since the electrochemical reaction is running at such a high temperature, a very sophisticated insulating system is protecting all the equipment from being damaged by the heat. The final step is to measure the amount, the purity of the oxygen and calculate the efficiency of the system before releasing the oxygen into the Martian atmosphere.

Since the Mars 2020 Perseverance Rover‘s MOXIE instrument is located inside of the rover’s body and you cannot really it from the outside unless you open it up, we may or may not replicate it. If we do make a MOXIE replica for our 1:2 Perseverance replica in the future, we will replicate the appearance structure, but not the functions, so you won’t need to worry about it getting too hot like the real Mars 2020 Perseverance Rover.