VOA科学技术2024--Evidence of 'Rotten Egg' Gas Found on Jupiter-like Exoplanet

Scientists say they have found evidence that the smelly molecule¹ hydrogen sulfide exists in the atmosphere of a Jupiter-like planet. Hydrogen sulfide is the chemical compound that gives rotten eggs their bad smell.

The planet is called HD 189733b. It is an exoplanet, a term used to describe planets that exist outside of our own solar system. It was discovered in 2005.

Scientists had already identified similarities between HD 189733b and Jupiter, the oldest and largest planet in our solar system. But the exoplanet was previously² not thought to hold hydrogen sulfide.

Astronomers³ who study this gas giant have said it is deep blue in color and that severe conditions exist in the atmosphere.

It has winds that can blow up to two kilometers per second. The exoplanet is believed to reach temperatures up to 930 degrees Celsius⁴ on the side facing the star that it orbits. Scientists also say it rains glass, which can be blown by fierce winds.

The weather on HD 189733b is so extreme, the American space agency NASA once described the planet as a "nightmare world."

New observations by NASA's James Webb Space Telescope suggest that this is the first exoplanet where hydrogen sulfide has been identified. Scientists say the discovery has helped give them a better understanding of this stormy world.

The finding was recently explained in a study appearing in the publication Nature.

One of the leaders of the research was astrophysicist Guangwei Fu of Johns Hopkins University in Maryland. He told Reuters, "This is not a planet we humans want to visit, but a valuable target for furthering our understanding of planetary science."

Fu said HD 189733b is known as a "hot Jupiter" planet. However, it orbits 170 times closer to its star than Jupiter does to the sun. It completes one orbit every two days. Jupiter takes about 12 years to orbit the sun.

Fu noted⁵ that hot Jupiters are not found often. "About less than one in 100 star systems have them," he said.

Fu said he thinks the newly discovered "stinky smell" just adds another interesting element to what is already known about the planet. It is 64 light-years from Earth, in the constellation⁶ Vulpecula. A light-year is the distance light travels in a year, about 9.5 trillion kilometers.

It is closer to Earth than many exoplanets. This makes it "bright and easy for detailed⁷ studies," Fu said. He noted, for example, that hydrogen sulfide would have been much harder to find on planets that are further away.

The Webb telescope - which became operational in 2022 - is able to observe a wider range of radiation wavelengths⁸ than earlier telescopes. This permits more detailed examinations of exoplanet atmospheres.

"Our research finds that HD 189733b is more similar to Jupiter than previously known," said Arizona State University astrophysicist Luis Welbanks. He was a member of the research team. "This planet is very much like Jupiter, but just hotter."

Jupiter, too, has small amounts of hydrogen sulfide in its atmosphere. But the exoplanet is about 10 percent larger than Jupiter in diameter and mass.

The Webb observations also confirmed earlier evidence showing the exoplanet has water and carbon dioxide in its atmosphere.

"With these three molecules⁹, we are able to count the amount of oxygen, carbon and sulfur¹⁰ the planet has," Welbanks said. That information, he added, gives scientists a chance to learn more about how the planet may have formed. It should also provide data on whether it is different from planets in our solar system.

Welbanks said the scientists are clearly not searching for life on such a hot, harsh planet. However, he noted that understanding its atmosphere permits them to "understand how physics and chemistry behave under different environments and to begin to put together the 'recipe' for forming planets."

Words in This Story

rotten - adj. suffering from decay

nightmare - v. a frightening or unpleasant experience

stinky - adj. having or producing an unpleasant smell

constellation - adj. a group of stars that forms a particular shape in the sky and has been given a name

range -n. a series of numbers or values that include the highest and lowest

harsh - adj. unpleasant, unkind or more severe than is necessary

recipe - n. a set of instructions explaining how to prepare and cook food

1 molecule   

n.分子，克分子

参考例句：

• A molecule of water is made up of two atoms of hygrogen and one atom of oxygen.一个水分子是由P妈̬f婘̬ 妈̬成的。
• This gives us the structural formula of the molecule.这种方式给出了分子的结构式。

2 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。

3 astronomers   

n.天文学者，天文学家( astronomer的名词复数 )

参考例句：

• Astronomers can accurately foretell the date,time,and length of future eclipses. 天文学家能精确地预告未来日食月食的日期、时刻和时长。 来自《简明英汉词典》
• Astronomers used to ask why only Saturn has rings. 天文学家们过去一直感到奇怪，为什么只有土星有光环。 来自《简明英汉词典》

4 Celsius   

adj.摄氏温度计的，摄氏的

参考例句：

• The temperature tonight will fall to seven degrees Celsius.今晚气温将下降到七摄氏度。
• The maximum temperature in July may be 36 degrees Celsius.七月份最高温度可能达到36摄氏度。

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 constellation   

n.星座n.灿烂的一群

参考例句：

• A constellation is a pattern of stars as seen from the earth. 一个星座只是从地球上看到的某些恒星的一种样子。
• The Big Dipper is not by itself a constellation. 北斗七星本身不是一个星座。

7 detailed   

adj.详细的，详尽的，极注意细节的，完全的

参考例句：

• He had made a detailed study of the terrain.他对地形作了缜密的研究。
• A detailed list of our publications is available on request.我们的出版物有一份详细的目录备索。

8 wavelengths   

n.波长( wavelength的名词复数 )；具有相同的/不同的思路；合拍；不合拍

参考例句：

• I find him difficult to talk to—we're on completely different wavelengths. 我没法和他谈话，因为我们俩完全不对路。 来自《简明英汉词典》
• Sunlight consists of different wavelengths of radiation. 阳光由几种不同波长的射线组成。 来自辞典例句

9 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。

10 sulfur   

n.硫，硫磺（=sulphur）

参考例句：

• Sulfur emissions from steel mills become acid rain.炼钢厂排放出的硫形成了酸雨。
• Burning may produce sulfur oxides.燃烧可能会产生硫氧化物。