VOA科学技术2023--NASA Rover Finds New Evidence of Organic Matter on Mars

NASA Rover Finds New Evidence of Organic Matter on Mars

Scientists say they have found new evidence of organic matter on Mars that could be linked to past life on the planet.

The Perseverance¹ explorer, which is operated by the American space agency NASA, discovered the organic materials. The explorer, or rover, has been collecting data on Mars since landing on the Red Planet in February 2021.

The goal, or mission, of Perseverance is to collect Martian soil and rock material as part of a search for signs of ancient life. Scientists on Earth using the equipment on the rover examine this material as closely as possible. The collected soil and rocks are to be picked up in future missions and returned to Earth for examination.

Researchers said the latest findings suggest the presence on the Martian surface of the same kinds of carbon "signals" that are linked to living organisms on Earth. The presence of carbon may suggest that biological life once existed on Mars. But the carbon material could also be related to nonbiological processes.

In the past, data from two other NASA explorers – the Phoenix² lander and the Curiosity rover – found evidence of organic carbon on the surface of Mars. But both of those discoveries were made with gas-based methods used for examining organic matter. The latest findings were made through a different method.

This time, the research team used an instrument attached to Perseverance's robotic arm known as SHERLOC. It uses cameras, spectrometers and a laser to search for organic matter and minerals, NASA said. The instrument centers on materials that might have been changed by watery³ environments and could provide biological evidence of past life.

One of the leaders of the latest research was Amy Williams, an astrobiologist and assistant professor at the University of Florida. She was one of the writers of a study that describes the latest findings in the publication Nature. The study suggests the new research method provided evidence "of a more intricate organic geochemical cycle on Mars than previously⁴ understood."

Williams works on the Perseverance mission team. She said in a statement that the SHERLOC instrument appears to have observed several kinds of organic carbon matter. She added that the discovery "has implications for understanding the carbon cycle on Mars," as well as the possibility that the planet once supported life.

Williams said SHERLOC was very effective at mapping the positions of organic molecules⁵ and minerals on rock surfaces around an area of Mars called Jezero Crater⁶.

Ashley Murphy was another writer of the study. She is a research scientist at the Planetary Science Institute in Arizona. Murphy said the SHERLOC instrument produces "the spatial⁷ resolution needed to observe important mineral-organic relationships" to study possible biological signals.

"The big takeaway here is, with SHERLOC's grain-by-grain resolution we can finally observe variation in organic preservation⁸ within the rocks on Mars," Murphy said. She added, "This is also one of the first reports of (possible) organics in Jezero Crater."

Scientists believe Jezero Crater contains the remains⁹ of an ancient river system. NASA considers the area a good place to look for possible signs of past life. Scientists believe if life ever existed on Mars, it would have been present 3 to 4 billion years ago, when water flowed freely on the planet.

Williams suggested the latest findings mark important progress in the search for signs of ancient life forms on Mars. "We are just now scratching the surface of the organic carbon story on Mars, and it is an exciting time for planetary science."

Words in This Story

spectrometer – n. an instrument that measures levels of chemical elements and gases in the Martian atmosphere

intricate –adj. having fine detail or made of many parts

imply – v. to suggest or show something, without saying it directly

spatial – adj. relating to the position, area and size for things

resolution – n. a measure of the sharpness of an image or the fineness a device operates at

takeaway –n. a fact or idea that comes from a discussion or meeting

variation – n. a difference in amount or quality

scratch the surface – idiom. to deal with only a small part of a problem or subject

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 phoenix   

n.凤凰，长生(不死)鸟；引申为重生

参考例句：

• The airline rose like a phoenix from the ashes.这家航空公司又起死回生了。
• The phoenix worship of China is fetish worship not totem adoration.中国凤崇拜是灵物崇拜而非图腾崇拜。

3 watery   

adj.有水的，水汪汪的；湿的，湿润的

参考例句：

• In his watery eyes there is an expression of distrust.他那含泪的眼睛流露出惊惶失措的神情。
• Her eyes became watery because of the smoke.因为烟熏，她的双眼变得泪汪汪的。

4 previously   

adv.以前，先前（地）

参考例句：

• The bicycle tyre blew out at a previously damaged point.自行车胎在以前损坏过的地方又爆开了。
• Let me digress for a moment and explain what had happened previously.让我岔开一会儿，解释原先发生了什么。

5 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。

6 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。

7 spatial   

adj.空间的，占据空间的

参考例句：

• This part of brain judges the spatial relationship between objects.大脑的这部分判断物体间的空间关系。
• They said that time is the feeling of spatial displacement.他们说时间是空间位移的感觉。

8 preservation   

n.保护，维护，保存，保留，保持

参考例句：

• The police are responsible for the preservation of law and order.警察负责维持法律与秩序。
• The picture is in an excellent state of preservation.这幅画保存得极为完好。

9 remains   

n.剩余物，残留物；遗体，遗迹

参考例句：

• He ate the remains of food hungrily.他狼吞虎咽地吃剩余的食物。
• The remains of the meal were fed to the dog.残羹剩饭喂狗了。