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The Perseverance rover, which has been on Mars since July 2020, was able to extract oxygen from the planet’s atmosphere for the first time. Understanding what this event means for future space travel
The atmosphere of Mars is significantly different from the Earth’s – it is much less dense and almost 96% consists of carbon dioxide, therefore, people will not be able to breathe Martian air. However, the latest news proves that it is still possible to obtain oxygen on Mars. We tell how we managed to get oxygen and whether it brings us closer to traveling to the Red Planet.
How did you get oxygen?
Before being sent to Mars, the Perseverance robot was equipped with seven scientific developments aimed at studying the planet, but now all the attention is directed to a device called MOXIE.
MOXIE is a whole experimental system aimed at the utilization and processing of local resources, in this case, into oxygen. In other words, MOXIE creates oxygen in the same way that trees do, inhaling carbon dioxide and exhaling oxygen. But the recycling process involves a lot of detail, and Mars’ atmosphere is thinner than Earth’s and is 96% carbon dioxide. First, MOXIE draws Martian “air” into itself with a special pump, then, using an electrochemical process, separates one oxygen atom from each carbon dioxide molecule. Such a conversion requires high temperatures – about 800 ° C, so the system is equipped with heat-resistant materials, and the surface is completely covered with a thin layer of gold, which perfectly reflects infrared rays and does not allow high temperatures to damage other parts of Perseverance. As the gases pass through the system, MOXIE analyzes how much oxygen is being produced, how pure it is, and how efficient the machine is. After each test, all gases are vented back into the Martian atmosphere.
Can we now breathe oxygen created on Mars?
Not really. The fact is that MOXIE itself is a toaster-sized experimental prototype built into Perseverance, not a full-fledged standalone system. Specifically, this device will not be able to produce enough oxygen for a long mission: for a year of work on the surface of Mars, four astronauts will need about 1 ton of oxygen, and on its first run, MOXIE produced, even according to NASA, a rather modest mass – about 5 g, which is enough for 10 minutes of one person’s breath. But the current prototype is not designed for large volumes, the main goal of scientists is to see if it can cope with the main technical task, namely, to produce about 6 g of oxygen of 98% purity at least ten times per hour.
The first launch was quite successful, but more difficult tasks lie ahead for MOXIE. Since the future full-fledged system will have to work under all weather conditions on Mars, the next nine MOXIE test cycles will take place at different times of the day, different temperatures and, if possible, even during dust storms, which can be very dangerous not only for future astronauts, but and for robots: in 2019, due to a giant storm, the Opportunity rover stopped communicating, and NASA was forced to end the mission.
What will it give to space expeditions?
По сути, речь идет о реальной возможности не только отправить, но и вернуть астронавтов домой с Марса. Конечно, кислород нужен самому экипажу, но научный руководитель проекта MOXIE Майкл Хэтч считает это лишь приятным бонусом, а главной целью — обеспечение достаточным количеством кислорода ракеты, чтобы произвести запуск с поверхности планеты. Чтобы сжечь топливо во время запуска, космическому кораблю понадобится около 25 т кислорода. Везти такой объем с Земли на Марс очень дорого и небезопасно.
Therefore, the success of the small MOXIE showed scientists the most important thing – the technology works, which means that NASA’s manned expedition to Mars by 2030 is becoming more and more real. The development of a new prototype is already underway, and in the near future the updated MOXIE will be almost like Perseverance itself – weighing about 1 ton, a little larger than a household stove, and the device will already produce tons of oxygen.
Another important consequence of MOXIE’s success is a step towards improved systems for the recovery and recycling of local resources. In the future, such devices will be able to produce not only oxygen from extraterrestrial products, but also, for example, drinking water, building materials, rocket fuel, hygiene products, and even create conditions for growing plants. This means that people on other planets will not depend on earthly resources, but will be able to get everything they need on their own on other planets, which is critical for long-term space missions. NASA expects to demonstrate and test such technologies before an expedition to Mars during the Artemis mission to the Moon in 2024 – as part of the Lunar Surface Innovation Initiative, it is planned to create products using lunar materials – for example, convert ice on the Moon into drinking water.
Are there other ways to get oxygen on Mars?
There are alternative approaches – for example, scientists from the State Research University of North Carolina suggest that oxygen can be obtained from plants grown directly on Mars. Work is already underway to create such plants that can survive in the conditions of the Red Planet. The idea is to combine the characteristics of extremophile microorganisms, which can live in the most adverse conditions on Earth, with plants. To do this, the technique of genetic separation is used – the necessary genes are separated from extremophiles and introduced into plants. But even such hybrids cannot be planted in the very soil of Mars, but presumably they will be able to grow in a greenhouse on a Martian base, although conditions there will still be far from earthly. If the experiment is successful and the hybrids take root on Mars, they could provide astronauts with oxygen, food, and even medicine.
Another possible way to get oxygen on Mars has come up with scientists from Washington University in St. Louis: Professor Vijay Ramani and his team suggest using salt lakes under the surface of Mars for this. In 2020, a network of salt lakes was discovered under the glaciers at the South Pole of the planet – due to the high concentration of salt, the freezing point is lowered, and water can be in liquid form. The technique Ramani is working on involves taking water from such lakes and electrolysing it—separating it into hydrogen and oxygen. Scientists expect that in 10-15 years their development can complement MOXIE and other resource processing systems.