VOA科学技术2023--New Space Telescope Aims to Show 'Dark Universe'

New Space Telescope Aims to Show 'Dark Universe'

European astronomers¹ released the first images from the new Euclid space telescope last week.

The European Space Agency (ESA) and the U.S. space agency, NASA, designed Euclid to study dark matter and dark energy. Scientists think those hidden forms of matter and energy make up 95 percent of the universe.

ESA is leading the six-year mission with NASA as a partner. ESA said the images were the most detailed² of their kind. They show the telescope's ability to observe billions of galaxies³ up to 10 billion light years away.

The images covered four areas of the sky. They include 1,000 galaxies belonging to the Perseus cluster of galaxies 240 million light years away. In the background, the image shows more than 100,000 galaxies, ESA said.

The cluster is called the Perseus cluster because it appears in the star group, or constellation⁴, Perseus.

Scientists believe such large structures like the Perseus cluster could only have formed if dark matter exists.

ESA's science director Carole Mundell said, "We think we understand only 5 percent of the universe: that's the matter that we can see."

"The rest of the universe we call dark," she continued, "because it doesn't produce light...But we know its effect because we see the effect on visible matter."

One sign of dark matter's hidden force is that galaxies rotate more quickly than scientists expect.

Mundell said it seems to have the effect of pulling together some of the largest structures in the universe, like groups of galaxies.

Dark energy is a new mystery

In the 1990s, scientists largely established the existence of dark matter after studying exploding stars called supernovas. That work resulted in a 2011 Nobel Prize shared between three U.S.-born scientists.

Looking at images from the earlier Hubble Space Telescope, scientists came to believe that the universe was not only expanding but that it was expanding faster and faster. That surprising discovery relied on a new concept: dark energy.

A new galaxy⁵ map

Euclid has been in a period of testing since its launch. Now it will start taking the images to make a 3D, or three-dimensional, map covering about a third of the sky. Scientists will use that map to look for small differences caused by the dark universe. Scientists hope the new understanding of dark energy and matter will help us learn about how galaxies formed, and why they are found across the universe.

Mundell said, "The purpose of the Euclid mission is really to start to probe that dark sector⁶ of the universe in ways that we've been unable to presently with current ground and space missions."

She added that the Perseus cluster is a good example of this huge gathering⁷ of mass. "We think there's lots of dark matter in that cluster and pulling these galaxies together."

A SpaceX Falcon⁸ 9 rocket launched Euclid from Florida in July.

The mission is expected to last six years. However, ESA hopes that Euclid will continue another six months if there is enough fuel to keep it in orbit around the sun. Euclid is orbiting the sun about 1.5 million kilometers away from Earth at "Lagrange Point Two," or L2. That is a place where the gravity of the sun, moon and Earth are balanced. A spacecraft can stay there, using less fuel. NASA's James Webb Space Telescope is also at L2, but it is not in danger of crashing into Euclid.

Other images released by ESA included an unusual galaxy with no exact form. Another was a spiral galaxy, sometimes called the "Hidden Galaxy," which looks much like our home galaxy, the Milky⁹ Way.

Speaking of the Perseus cluster, Mundell said, "You'll also see lots of background galaxies there as well, which is phenomenal. I think I spotted¹⁰ a new one there last night."

Words in This Story

galaxy – n. a very large group of stars and planets that extends over many billions of light years

light year – n. the distance that light travels in one year; 9.46 trillion kilometers

cluster – n. a group of objects gathered close together

rotate – v. to turn with a circular movement

probe – v. to ask questions or try to discover facts about something

sector – n. a part of something or area

spiral – adj. a shape that winds around and around, with each curve above or outside the previous one

phenomenal – adj. unusually great or good

1 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》

2 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。

3 galaxies   

星系( galaxy的名词复数 )； 银河系； 一群（杰出或著名的人物）

参考例句：

• Quasars are the highly energetic cores of distant galaxies. 类星体是遥远星系的极为活跃的核心体。
• We still don't know how many galaxies there are in the universe. 我们还不知道宇宙中有多少个星系。

4 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。

5 galaxy   

n.星系；银河系；一群(杰出或著名的人物)

参考例句：

• The earth is one of the planets in the Galaxy.地球是银河系中的星球之一。
• The company has a galaxy of talent.该公司拥有一批优秀的人才。

6 sector   

n.部门，部分；防御地段，防区；扇形

参考例句：

• The export sector will aid the economic recovery. 出口产业将促进经济复苏。
• The enemy have attacked the British sector.敌人已进攻英国防区。

7 gathering   

n.集会，聚会，聚集

参考例句：

• He called on Mr. White to speak at the gathering.他请怀特先生在集会上讲话。
• He is on the wing gathering material for his novels.他正忙于为他的小说收集资料。

8 falcon   

n.隼，猎鹰

参考例句：

• The falcon was twice his size with pouted feathers.鹰张开羽毛比两只鹰还大。
• The boys went hunting with their falcon.男孩子们带着猎鹰出去打猎了。

9 milky   

adj.牛奶的，多奶的；乳白色的

参考例句：

• Alexander always has milky coffee at lunchtime.亚历山大总是在午餐时喝掺奶的咖啡。
• I like a hot milky drink at bedtime.我喜欢睡前喝杯热奶饮料。

10 spotted   

adj.有斑点的，斑纹的，弄污了的

参考例句：

• The milkman selected the spotted cows,from among a herd of two hundred.牛奶商从一群200头牛中选出有斑点的牛。
• Sam's shop stocks short spotted socks.山姆的商店屯积了有斑点的短袜。