Spiiker新聞萬(wàn)花筒，VOA新聞，帶您看世界，聽(tīng)世界，

感受世界的點(diǎn)點(diǎn)滴滴。

練聽(tīng)力，提能力，小編與您共努力！

 

Gamma Ray Observatory to Open Soon in Mexico

American and Mexican scientists have completed construction of the world's largest gamma ray observatory, situated high in central Mexico’s Sierra Negra Mountain. The observatory's huge array of water-based detectors will soon start discovering secrets about black holes and supernovas.

Extreme cosmic events, such as explosions of stars, pulsars or black holes, emit huge bursts of highly-charged particles, called gamma rays, that under certain circumstances can travel faster than the speed of light.

Scientists say the rays are so powerful that some of them can be detected coming from distances up to 10 billion light years away.

Jordan Goodman, a physics professor at the University of Maryland, said, “They are [the] highest-energy light so they let us understand where the highest energy particles in the universe come from. So our idea is to build this observatory to give us a wide field view of the sky at the highest energies.”

Cosmic glow

When cosmic gamma rays hit a medium like water, they create a soft bluish glow called Cherenkov electromagnetic radiation, a glow that can also be seen at the cores of nuclear reactors.

Three hundred tightly-sealed water tanks at the High Altitude Water Cherenkov Experiment observatory, or HAWC for short, also contain sensors that detect and record Cherenkov radiation.

By measuring the angle and intensity at which gamma rays hit the sensors, scientists can calculate where they came from.

Volcanic site

Goodman said along with studying deep space, the new observatory also can study our own star.

“This technique is unusual because someone yesterday, at the conference we had, said, 'you know, we should look at gamma rays from the sun, very high energy.' No one who does a telescope can look at the sun but we can look at the sun because we don't use the daylight, we use the gamma rays,” said Goodman.

The site, at the bottom of an extinct volcano in central Mexico, was chosen for its favorable climate conditions.

After 10 years it will be dismantled and the site's environment will be returned to its original condition.

 

詞匯解析

conservative

難度：3星常用詞匯，屬常用6000詞

英漢解釋

adj.保守的；守舊的

n.保守派(黨)；保守的人

參考例句

用作形容詞 (adj.)

The professor's a radical in politics but a conservative dresser.

教授在政治上是激進(jìn)派,但衣著卻很守舊。

用作名詞 (n.)

He listed himself as a conservative.

他自稱是一個(gè)保守主義者。

************************

aggressive

難度：4星核心詞匯，屬常用3000詞

英漢解釋

adj.侵略的；進(jìn)攻性的；好斗的；有進(jìn)取心的

參考例句

用作形容詞 (adj.)

His style of argument in meetings is not so much aggressive as pertinacious.

他在會(huì)議上的辯論態(tài)度并非鋒芒逼人而是堅(jiān)持己見(jiàn)。

But what impresses most is that they are aggressive in their career and responsible to their families and respectful to females.

但最印象深刻的,上海男人在事業(yè)上有進(jìn)取心,對(duì)家庭有很強(qiáng)的責(zé)任感,而且尊重女性。

************************

northeast

難度：2星擴(kuò)展詞匯，屬常用10000詞

英漢解釋

n.東北

adj.東北的；向東北的；來(lái)自東北的

adv.向東北；來(lái)自東北

參考例句

用作名詞 (n.)

At this point the road turns northeast.

路在這里轉(zhuǎn)向東北。

用作形容詞 (adj.)

Hereby he is presenting the fellows in Northeast China.

在這里他向我們呈現(xiàn)的是東北的父老鄉(xiāng)親。

用作副詞 (adv.)

Another ocean current flows northeast along the steep continental shelf.

還有一股沿陡峭陸架坡向東北流動(dòng)的海流。

************************

assemble

難度：3星常用詞匯，屬常用6000詞

英漢解釋

v.集合；收集；裝配

參考例句

用作動(dòng)詞 (v.)

The students assembled in the school garden.

學(xué)生們?cè)谛@集合。

************************

yearly

難度：3星常用詞匯，屬常用6000詞

英漢解釋

adj.每年的

adv.每年地；一年一次地

參考例句

用作形容詞 (adj.)

Many Greek cities had to send yearly tribute to Athens.

許多希臘城市不得不每年向雅典進(jìn)貢。

用作副詞 (adv.)

I get a physical examination yearly.

我一年做一次身體檢查。

************************

craft

難度：3星常用詞匯，屬常用6000詞

英漢解釋

n.工藝；手藝；狡詐；船舶；航空器；行會(huì)成員

vt.手工制作；精心制作

參考例句

用作名詞 (n.)

He graduated from a school of crafts and arts.

他畢業(yè)于一所工藝美術(shù)學(xué)校。

用作及物動(dòng)詞 (vt.)

He told us a carefully crafted story.

他給我們講了一個(gè)精心編織的故事。

************************

marine

難度：4星核心詞匯，屬常用3000詞

英漢解釋

adj.海的；海事的；海生的；航海的

n.海運(yùn)業(yè)；船舶；水兵

參考例句

用作形容詞 (adj.)

His father is a marine biologist.

他父親是位海洋生物學(xué)家。

用作名詞 (n.)

He sought an officer's berth in the merchant marine.

他在商船上找了一個(gè)高級(jí)船員的職位。

 

See more information, you can visit us

英語(yǔ)口語(yǔ)測(cè)試  http://www.demadzwfz.com/daily/ 

在線學(xué)英語(yǔ)口語(yǔ) http://www.demadzwfz.com/english-plaza.jsp