1 . In the endless sky, the unaided human eye should be able to perceive several thousand stars on a clear, dark night. Unfortunately, growing light pollution has impeded people from the nightly view.

New citizen-science-based research throws alarming light on the problem of “sky glow”-the diffuse illumination (漫射照明) of the night sky that is a form of light pollution. The data came from crowd-sourced observations collected from around the world as part of Globe at Night, a program developed by astronomer Connie Walker.

Light pollution has harmful effects on the practice of astronomy but also on human health and wildlife, since it disturbs the cycle from sunlight to starlight that biological systems have evolved alongside. Furthermore, the loss of visible stars is a great loss of human cultural heritage. Until relatively recently, humans throughout history had an impressive view of the starry night sky, and the effect of this nighty spectacle (壮观) is evident in ancient cultures.

Globe at Night has been gathering data on star visibility since 2006. Anyone can submit observations through the Globe at Night web application. Participants record which one best matches what they can see in the sky without any telescopes or other instruments.

Researchers find that the loss of visible stars indicates an increase in sky brightness of 9.6% per year while roughly 2% is measured by satellites. Existing satellites are not well suited to measuring sky glow as it appears to humans, because they can not detect wavelengths shorter than 500 nanometers (纳米). White LEDs, with shorter wavelengths under 500 nanometers, now are increasingly commonly used in outdoor lighting. But human eyes are more sensitive to these shorter wavelengths at nighttime. Space-based instruments do not measure light from windows, either. But these sources are significant contributors to sky glow us seen from the ground.

“The increase in sky glow over the past decade underlines the importance of redoubling our efforts and developing new strategies to protect dark skies,” said Walker. “The Globe at Night dataset is necessary in our ongoing evaluation of changes in sky glow, and we encourage whoever can to get involved to help protect the starry night sky.”

1. What does the underlined word “impeded” in the first paragraph mean?

A．separated.

B．disabled.

C．demanded.

D．protected.

2. What does the loss of visible stars lead to?

A．Poorer human health.	B．Fewer wildlife species.
C．More delicate biological systems.	D．Less nightly culture elements of the sky.

3. What does the author stress in paragraph 5?

A．Crowd sourced data are invaluable	B．Shorter wavelengths are hard to detect.
C．Satellites play a vital role.	D．White LEDs are widely used.

4. What can be inferred from Walker’s words?

A．Their consistent efforts pay off.	B．The dataset needs to be updated.
C．The sky glow has been over-emphasized.	D．More participants are expected to join in.

4 . If humans were truly at home under the light of the moon and stars, we would go in darkness happily, the midnight world as visible to us as it is to the vast number of nocturnal (夜间活动的) species on this planet. Instead, we are diurnal creatures, with eyes adapted to living in the sun’s light. This is a basic evolutionary fact, even though most of us don’t think of ourselves as diurnal beings. Yet it’s the only way to explain what we’ve done to the night: We’ve engineered it to receive us by filling it with light.

The benefits of this kind of engineering come with consequence called light pollution whose effects scientists are only now beginning to study. Light pollution is largely the result of bad lighting design, which allows artificial light to shine outward and upward into the sky. Ill-designed lighting washes out the darkness of night and completely changes the light levels and light rhythms to which many forms of life, including ourselves, have adapted. Wherever human light spills into the natural world, some aspect of life is affected.

In most cities the sky looks as though it has been emptied of stars, leaving behind a vacant haze (霾) that mirrors our fear of the dark. We’ve grown so used to this orange haze that the original glory of an unlit night—dark enough for the planet Venus to throw shadow on Earth—is wholly beyond our experience, beyond memory almost.

We’ve lit up the night as if it were an unoccupied country, when nothing could be further from the truth. Among mammals alone, the number of nocturnal species is astonishing. Light is a powerful biological force, and on many species it acts as a magnet. The effect is so powerful that scientists speak of songbirds and seabirds being “captured” by searchlights on land or by the light from gas flares on marine oil platforms. Migrating at night, birds tend to collide with brightly lit tall buildings.

Frogs living near brightly lit highways suffer nocturnal light levels that are as much as a million times brighter than normal, throwing nearly every aspect of their behavior out of joint, including their nighttime breeding choruses. Humans are no less trapped by light pollution than the frogs. Like most other creatures, we do need darkness. Darkness is as essential to our biological welfare, to our internal clockwork, as light itself.

Living in a glare of our making, we have cut ourselves off from our evolutionary and cultural heritage—the light of the stars and the rhythms of day and night. In a very real sense light pollution causes us to lose sight of our true place in the universe, to forget the scale of our being, which is best measured against the dimensions of a deep night with the Milky Way—the edge of our galaxy—arching overhead.

1. According to the passage, human being ________.

A．are used to living in the daylight	B．prefer to live in the darkness
C．were curious about the midnight world	D．had to stay at home with the light of the moon

2. The writer mentions birds and frogs to ________.

A．show how light pollution affects animals

B．provide examples of animal protection

C．compare the living habits of both species

D．explain why the number of certain species has declined

3. It is implied in the passage that ________.

A．human beings are curious about the outer space

B．human beings should reflect on their position in the universe

C．light pollution does harm to the eyesight of animals

D．light pollution has destroyed some of the world heritages

4. What might be the best title for the passage?

A．The Magic Light	B．The Orange Haze
C．The Disappearing Night	D．The Rhythms of Nature

5 . There is an increasing alarm about the extent of microplastics pollution, which has been found everywhere from Everest to the Arctic. However, it turns out there’s an even smaller and more poisonous form of plastic pollution entering remote reaches of the globe. A new study published in Environmental Research found significant quantities of nanoplastics (纳米塑料) in ice samples from both the North and South Poles.

“Now we know that nanoplastics are transported to these corners of the Earth in these quantities. This indicates that nanoplastics are really a bigger pollution problem than we thought,” study lead author Dusan Materic said in a press release.

Nanoplastics are plastics that are smaller than a micrometer in size. Their small size means they are more difficult to study than microplastics, or plastics between five millimeters and a micrometer. But they may be even more dangerous.

“Nanoplastics are very toxicological active compared to, for instance, microplastics, and that’s why this is very important,” Materic said.

Materic and his team used new methods to measure nanoplastic pollution in ice samples from Greenland and Antarctica. They sampled a 14-meter-deep ice core from the Greenland ice cap and sea ice from Antarctica’s McMurdo Sound. They found that there were an average of 13.2 nanograms per-milliliter of nanoplastics in the Greenland ice and an average of 52.3 nanograms per milliliter in the Antarctic ice

But what was even more surprising than the amount of nanoplastics in the remote ice was just how long they had sat there. “In the Greenland core, we see nanoplastic pollution happening all the way from the 1960s. So organisms, despite the lack of the solid evidence, likely all over the world, have been exposed to it for quite some time now,” Materic said.

The study also looked at the types of plastic present in the samples. Half of the Greenland nanoplastics were polyethylene (PE), the kind of plastic used for plastic bags and packaging. A quarter came from tires and a fifth were polyethylene terephthalate (PET), which is used for clothing and bottles.

1. Why should researchers focus more on nanoplastics?

A．They are smaller but more dangerous.

B．They are more important to science.

C．They are easily polluted by ocean water.

D．They are more active in cold surroundings.

2. What can we learn about nanoplastics?

A．The North and South poles are the birthplace of nanoplastics.

B．Nanoplastics have less influence on the planet than microplastics.

C．Nanoplastics have been existing since the 1960s throughout the world.

D．Nanoplastics found in the samples are widely used in the daily life.

3. What does the underlined word “it” refer to in Paragraph 6?

A．The Greenland core.

B．The Antarctic ice.

C．The amount of nanoplastics.

D．Nanoplastics pollution.

4. What’s the main idea of this passage?

A．Mircoplastics prove to be more dangerous.

B．Nanoplastics pose a threat to people’s life.

C．Nanoplastics are making their way to the poles.

D．Mircoplastics set the alarm bells ringing.