VOA科学技术2023--NASA: Oxygen-producing Device on Mars Performed above Expectations

NASA: Oxygen-producing Device on Mars Performed above Expectations

The American space agency NASA says a device placed on Mars to produce oxygen has performed better than expected in a series of experiments.

The system is called MOXIE. It is designed to change, or convert, carbon dioxide captured from the Mars atmosphere into oxygen. The instrument works through a process called electrolysis. This process uses extreme heat to separate oxygen atoms from molecules¹ of carbon dioxide.

Carbon dioxide makes up about 95 percent of the Martian atmosphere, NASA reports. The rest is mostly molecular² nitrogen and argon. Molecular oxygen makes up just 0.16 percent of the Martian atmosphere.

But future exploration of Mars and possibly other planets by humans will require a large supply of oxygen. NASA has said the chemical element will be necessary for astronauts to breathe and to produce rocket fuel for launches carried out from the Martian surface.

NASA financed the MOXIE demonstration³ experiment. A team from the Massachusetts Institute of Technology (MIT) created the device.

The MOXIE instrument was carried to Mars aboard NASA's Perseverance⁴ explorer, or rover. Perseverance arrived on the Red Planet in February 2021. The device is a box-shaped instrument attached to the rover.

NASA reported its first results with the MOXIE system in April 2021. At the time, the space agency reported the device had successfully converted carbon dioxide from the Martian atmosphere into oxygen. In the first experiment, MOXIE produced 5.4 grams of oxygen in one hour. NASA then carried out a series of additional experiments to test the effectiveness of the system.

In a statement issued earlier this month, leaders of the demonstration project said MOXIE had completed its 16th and final experiment. They noted⁵ the device's "impressive performance" had proven it was possible to capture oxygen from the Martian atmosphere. Such oxygen "could help supply breathable air or rocket propellant to future astronauts," the statement said.

NASA said that MOXIE had produced a total of 122 grams of oxygen since Perseverance landed on Mars. This amount is about what a small dog would breathe in 10 hours. While the amount of oxygen is small, it represented the first experimental capture of a natural resource from the environment of another planet.

When working at its highest level of effectiveness, the instrument was able to produce 12 grams of oxygen in one hour. NASA says this is twice as much as its engineers first estimated the system could produce.

The MOXIE team has also been measuring the purity of the oxygen the device produces. Overall, it has reported the instrument produced oxygen that was at least 98 percent pure.

The latest experiments with MOXIE on Mars are designed to help NASA build a much larger version of the system. A full-sized device could be deployed⁶ on Mars in the future.

A NASA explanation of the instrument states: "The goal of a Big MOXIE would be to make and store all the oxygen that the astronaut and their rocket would need for their mission before they even launch." Such a system would need to make between 2,000 to 3,000 grams of oxygen per hour, the space agency noted.

Trudy Kortes is the director of technology demonstrations⁷ at NASA Headquarters in Washington D.C. She said the agency was pleased to be able to support such a technology. "By proving this technology in real-world conditions, we've come one step closer to a future in which astronauts ‘live off the land' on the Red Planet," Kortes said.

MIT's Michael Hecht leads the MOXIE development operation. He said in a statement the team's work will next center on working on the larger version of MOXIE. In addition, scientists will need to create equipment to liquefy and store the produced oxygen.

Words in This Story

impressive – adj. making or attempting to make a marked impression

propellant – n. an explosive substance of fuel that causes something to move forward

mission – n. a flight by an aircraft or spacecraft to perform a specific task

1 molecules   

分子( molecule的名词复数 )

参考例句：

• The structure of molecules can be seen under an electron microscope. 分子的结构可在电子显微镜下观察到。
• Inside the reactor the large molecules are cracked into smaller molecules. 在反应堆里，大分子裂变为小分子。

2 molecular   

adj.分子的；克分子的

参考例句：

• The research will provide direct insight into molecular mechanisms.这项研究将使人能够直接地了解分子的机理。
• For the pressure to become zero, molecular bombardment must cease.当压强趋近于零时，分子的碰撞就停止了。

3 demonstration   

n.表明，示范，论证，示威

参考例句：

• His new book is a demonstration of his patriotism.他写的新书是他的爱国精神的证明。
• He gave a demonstration of the new technique then and there.他当场表演了这种新的操作方法。

4 perseverance   

n.坚持不懈，不屈不挠

参考例句：

• It may take some perseverance to find the right people.要找到合适的人也许需要有点锲而不舍的精神。
• Perseverance leads to success.有恒心就能胜利。

5 noted   

adj.著名的，知名的

参考例句：

• The local hotel is noted for its good table.当地的那家酒店以餐食精美而著称。
• Jim is noted for arriving late for work.吉姆上班迟到出了名。

6 deployed   

（尤指军事行动）使展开( deploy的过去式和过去分词 )； 施展； 部署； 有效地利用

参考例句：

• Tanks have been deployed all along the front line. 沿整个前线已部署了坦克。
• The artillery was deployed to bear on the fort. 火炮是对着那个碉堡部署的。

7 demonstrations   

证明( demonstration的名词复数 )； 表明； 表达； 游行示威

参考例句：

• Lectures will be interspersed with practical demonstrations. 讲课中将不时插入实际示范。
• The new military government has banned strikes and demonstrations. 新的军人政府禁止罢工和示威活动。