VOA慢速英语--Saturn Becomes ‘Moon King’ with 20 New Discoveries

 

The planet Saturn¹ is being recognized as the “moon king” of our solar system.

Jupiter used to hold the record for most moons orbiting around it. It has 79. But scientists in the United States have announced the discovery of 20 new moons around Saturn. That gives the planet a new total of 82 moons.

The researchers made the discovery using the powerful Subaru telescope in Hawaii. They gathered information over a period of several years.

The team also used new computing² models to identify moons and follow orbiting activity.

Scott Sheppard led the research team. He is with the Carnegie Institution for Science in Washington, D.C. “Saturn is the moon king,” Sheppard told Reuters news agency.

The discovery was announced last week by the International Astronomical³ Union’s Minor⁴ Planet Center. The center is responsible for identifying all the world’s minor planets, comets and “outer natural satellites.” The organization also measures the orbital movements of such objects.

Researchers say the newly found moons are very small, measuring about five kilometers across. The team was able to discover them now because of better technology that became available in recent years. This includes more powerful telescopes and increased computing power.

Saturn is a gas planet made up mostly of hydrogen and helium. It is the second-largest planet in the solar system and the sixth from the sun. It measures about 116,000 kilometers across.

One of the newly identified moons orbits Saturn from a huge distance away, about 25 million kilometers from the planet. This is farther away than any of Saturn’s other moons. By comparison, Earth’s moon orbits about 386,000 kilometers from the planet.

Seventeen of the moons orbit Saturn backwards⁵. In other words, their movement is opposite of the planet's rotation⁶. The other three orbit in the same direction as the planet rotates.

The researchers said a number of the moons appear to have been formed from parts of larger moons. Those past moons likely broke up in crashes with other moons or with comets or asteroids⁸. This is similar to how some of Jupiter’s 79 moons were formed.

Sheppard said scientists can learn many new things from Saturn’s moons.

“These new moons show us the solar system was a very chaotic⁹ place in the distant past, with objects flying all over the place,” Sheppard said. He added that the moons are among the last pieces of evidence left over from the formation of the solar system. All other objects were either pushed out or became parts of other planets.

Sheppard hopes the discovery can help scientists keep learning more about how planets in our solar system came to be.

"Studying the orbits of these moons can reveal their origins, as well as information about the conditions surrounding Saturn at the time of its formation," he said.

Sheppard added that there are likely more moons around Saturn that are even smaller than the latest discoveries. But he says astronomers¹⁰ will need larger telescopes to find them.

The Carnegie Institution for Science is asking the public for help to name the newly discovered moons.

I’m Bryan Lynn.

Words in This Story

rotate – n. to turn in a circular direction

asteroid⁷ – n. a rocky object that goes around the sun like a planet

chaotic – adj. in a state of disorder¹¹

reveal – v. to give someone a piece of information that is surprising or that was previously¹² secret

origin – n. the cause of something, or where something begins or comes from

1 Saturn   

n.农神，土星

参考例句：

• 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。
• These comparisons suggested that Saturn is made of lighter materials.这些比较告诉我们，土星由较轻的物质构成。

2 computing   

n.计算

参考例句：

• to work in computing 从事信息处理
• Back in the dark ages of computing, in about 1980, they started a software company. 早在计算机尚未普及的时代（约1980年），他们就创办了软件公司。

3 astronomical   

adj.天文学的，（数字）极大的

参考例句：

• He was an expert on ancient Chinese astronomical literature.他是研究中国古代天文学文献的专家。
• Houses in the village are selling for astronomical prices.乡村的房价正在飙升。

4 minor   

adj.较小(少)的，较次要的；n.辅修学科；vi.辅修

参考例句：

• The young actor was given a minor part in the new play.年轻的男演员在这出新戏里被分派担任一个小角色。
• I gave him a minor share of my wealth.我把小部分财产给了他。

5 backwards   

adv.往回地，向原处，倒，相反，前后倒置地

参考例句：

• He turned on the light and began to pace backwards and forwards.他打开电灯并开始走来走去。
• All the girls fell over backwards to get the party ready.姑娘们迫不及待地为聚会做准备。

6 rotation   

n.旋转；循环，轮流

参考例句：

• Crop rotation helps prevent soil erosion.农作物轮作有助于防止水土流失。
• The workers in this workshop do day and night shifts in weekly rotation.这个车间的工人上白班和上夜班每周轮换一次。

7 asteroid   

n.小行星；海盘车(动物)

参考例句：

• Astronomers have yet to witness an asteroid impact with another planet.天文学家还没有目击过小行星撞击其它行星。
• It's very unlikely that an asteroid will crash into Earth but the danger exists.小行星撞地球的可能性很小，但这样的危险还是存在的。

8 asteroids   

n.小行星( asteroid的名词复数 )；海盘车，海星

参考例句：

• Asteroids,also known as "minor planets",are numerous in the outer space. 小行星，亦称为“小型行星”，在外太空中不计其数。
• Most stars probably have their quota of planets, meteorids, comets, and asteroids. 多数恒星也许还拥有若干行星、流星、彗星和小行星。

9 chaotic   

adj.混沌的，一片混乱的，一团糟的

参考例句：

• Things have been getting chaotic in the office recently.最近办公室的情况越来越乱了。
• The traffic in the city was chaotic.这城市的交通糟透了。

10 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》

11 disorder   

n.紊乱，混乱；骚动，骚乱；疾病，失调

参考例句：

• When returning back,he discovered the room to be in disorder.回家后，他发现屋子里乱七八糟。
• It contained a vast number of letters in great disorder.里面七零八落地装着许多信件。

12 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。