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NASA to Launch Newest Mars Explorer to Seek Signs of Life

The United States is preparing to return to the planet Mars. The U.S. space agency NASA plans to have a spacecraft, called Perseverance¹, deploy² a rover on the planet's surface. The vehicle has been called the brainiest Martian rover yet. NASA officials say its mission will be to search for signs of life on the Red Planet.

This will be the space agency's fifth rover to explore Mars. The first, named Sojourner³, was sent in 1997. Then came Spirit and Opportunity, which landed in 2004. The fourth rover, Curiosity, has been exploring the planet since 2012.

The missions have resulted in valuable information. The vehicles helped gather data showing Mars was not always the cold and empty place it is today. Experiments provided evidence that at one time, the planet held several chemical elements that may have supported life. These included running water, organic molecules⁴, and a more favorable climate.

In 2018, Curiosity found large amounts of organic molecules in 3.5 billion-year-old rock in an area that once had a large lake. Scientists have yet to show that the molecules were a product of biological processes linked to life as we know it.

NASA says Perseverance "aims to take the next step" in searching for signs of ancient microbial life. The rover will also study the planet's climate and surface materials.

Perseverance is NASA's largest, heaviest and most technology-loaded vehicle ever sent to Mars. The six-wheeled rover is three meters long, a little over two meters tall and weighs 1,000 kilograms. It has 19 cameras, two microphones and a two-meter-long robotic arm.

A machine connected to the robotic arm will drill down into the surface to gather rock and soil samples. These particles will then be put in special tubes and stored away for eventual⁵ return to Earth. NASA says the tubes went through an extreme cleaning and baking process to remove any microorganisms from Earth.

A mission to collect the samples is planned for 2026. NASA said that back on Earth, "we can investigate the samples with instruments too large and complex to send to Mars."

The rover is equipped with X-ray and imaging systems to study the chemical makeup⁶ of Martian surface materials and to identify possible organic compounds.

It will be a long trip for Perseverance, which is expected to reach the Jezero Crater⁷ on Mars in February 2021. The area is 45 kilometers wide and sits just north of the planet's equator.

Researchers suspect that a river flowed into a large body of water at Jezero between 3 and 4 billion years ago. This was the main reason the crater was chosen for the Perseverance mission, notes NASA project scientist Ken⁸ Farley.

The crater area is a promising⁹ place "for finding organic molecules and other potential signs of microbial life," he added.

One experiment planned for Perseverance will involve a device designed to convert carbon dioxide from Mars' atmosphere into oxygen. The experiment aims to demonstrate a way to produce the important gas, which could be used by astronauts or as fuel on future missions.

Perseverance also is carrying a small experimental helicopter called Ingenuity¹⁰. NASA says the 1.8 kilogram-aircraft will attempt its first flight a few months after arrival on Mars. NASA officials hope it will be the first helicopter to ever fly on another planet.

Ingenuity project leader MiMi Aung told The Associated Press the helicopter will start out like a baby bird, attempting to rise about 3 meters off the surface. It will then try to push forward into the planet's extremely thin atmosphere. Other flight tests will be carried out, with Ingenuity trying to go a little higher and farther each time. "It really is like the Wright brothers' moment," Aung said.

If the tests are successful, such helicopters could assist astronauts on future search and collection missions.

I'm Bryan Lynn.

Words in This Story

mission – n. an important task, usually involving travel somewhere

microbial – adj. relating to microbes (very small living things)

data – n. information, especially facts or numbers

drill– v. to make holes in hard materials with a machine

sample – n. a small amount of something to represent what the rest is or should be like

baking – n. making something hot by heating it

crater – n. a big hole

equator – n. an imaginary line drawn¹¹ around the middle of a planet

potential – adj. having or showing the capacity to become or develop into something in the future

convert – v. to cause to change in form

1 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。

2 deploy   

v.（军）散开成战斗队形，布置，展开

参考例句：

• The infantry began to deploy at dawn.步兵黎明时开始进入战斗位置。
• The president said he had no intention of deploying ground troops.总统称并不打算部署地面部队。

3 sojourner   

n.旅居者，寄居者

参考例句：

• The sojourner has been in Wales for two weeks. 那个寄居者在威尔士已经逗留了两个星期。 来自互联网
• A sojourner or a hired servant shall not eat of it. 出12:45寄居的、和雇工人、都不可吃。 来自互联网

4 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。

5 eventual   

adj.最后的，结局的，最终的

参考例句：

• Several schools face eventual closure.几所学校面临最终关闭。
• Both parties expressed optimism about an eventual solution.双方对问题的最终解决都表示乐观。

6 makeup   

n.组织；性格；化装品

参考例句：

• Those who failed the exam take a makeup exam.这次考试不及格的人必须参加补考。
• Do you think her beauty could makeup for her stupidity?你认为她的美丽能弥补她的愚蠢吗？

7 crater   

n.火山口，弹坑

参考例句：

• With a telescope you can see the huge crater of Ve-suvius.用望远镜你能看到巨大的维苏威火山口。
• They came to the lip of a dead crater.他们来到了一个死火山口。

8 ken   

n.视野，知识领域

参考例句：

• Such things are beyond my ken.我可不懂这些事。
• Abstract words are beyond the ken of children.抽象的言辞超出小孩所理解的范围.

9 promising   

adj.有希望的，有前途的

参考例句：

• The results of the experiments are very promising.实验的结果充满了希望。
• We're trying to bring along one or two promising young swimmers.我们正设法培养出一两名有前途的年轻游泳选手。

10 ingenuity   

n.别出心裁；善于发明创造

参考例句：

• The boy showed ingenuity in making toys.那个小男孩做玩具很有创造力。
• I admire your ingenuity and perseverance.我钦佩你的别出心裁和毅力。

11 drawn   

v.拖，拉，拔出；adj.憔悴的，紧张的

参考例句：

• All the characters in the story are drawn from life.故事中的所有人物都取材于生活。
• Her gaze was drawn irresistibly to the scene outside.她的目光禁不住被外面的风景所吸引。