4 . 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.”

5 . Nowadays, because of the popularity of modern traffic and modern communication technology, our world is becoming much smaller. Thus our life today is much easier than it was hundreds of years ago, but meanwhile it has brought new problems, the biggest one of which is pollution. For a long time ever since, man has been polluting the earth. The more people, the more pollution.

To pollute means to make things dirty. Pollution comes in many ways. We see it, smell it, drink it and even hear it. Many years ago, the problem was not so serious because there were not so many people. When the land was used up or the river was dirty in one place, man moved to another place. But this is no longer true. Man is now slowly polluting the whole world.

Air pollution is still the most serious. It’s bad for all living things in the world, but it is not the only one kind of pollution. Water pollution kills our fish and pollutes our drinking water. Noise pollution makes us angry more easily.

Many countries are making rules to fight pollution. They stop people from burning coal in houses and factories in the city, and from putting dirty smoke into the air. Pollution by SO₂ is now the most dangerous kind of air pollution. It is caused by heavy traffic. We are sure that if there are fewer people driving, there will be less air pollution.

The earth is our home. We must take care of it. That means keeping the land, water and air clean. And we must take care of the rise in pollution at the same time.

The environment pollution was more and more serious today. We have no clean water to drink it because of water pollution. And when trees cut down, some animals disappear. There is more and more dirty smoke in the air. People’s health has been great affected by air, noise and water pollution. Many people have died of diseases causing by pollution. In order to live the better life, it’s time for us to protect our world. We should recycle, reduce and reuse things, what saves money and reduces pollution. Use things so long as possible. Don’t use plastic bag. Besides, we must plant more trees and stop people cutting it down. We hope our world will be more and more beautiful.

8 . Most of us are used to the sound we hear in daily life, such as music, the middle of the night.     1    . However, when these sounds of television, people talking on their phones and even pet dogs barking in the night keep you from sleeping all night or the traffic starts to give you a headache, they turn into noise pollution. For many of us, the concept of pollution is limited to nature an resources. However, noises that tend to damage the natural rhythm of life make environmental pollutants.

    2    . Man-made noises such as horns, airplanes and even cars can be too loud for our hearing range. Constant exposure to loud noise can easily result in the damage to our eardrums (耳膜) and lead to our loss of hearing.

Too much noise pollution in working areas such as offices, construction sites, bars and even in our homes can influence psychological health. Studies show that the occurrence of aggressive behavior, sleep disturbance, and constant stress can be linked to excessive (过度的) noise levels.     3    .

Loud noises can certainly influence our sleeping pattern.     4    , if we don’t have a good sleep at night. For example, our performance may go down i the office as well as at home. It is therefore recommended to take a sound sleep to give our body proper rest.

As of now, there do not exist many solutions to such pollution.     5    , when it comes to what an individual can do. Only when our understanding of noise pollution is complete can we take steps to get rid of it completely.

10 . Sleeping in a noisy room isn’t only distracting (使人分心的), and it can also harm your health. Although researchers have known for decades that long­term loud noises can harm us, it’s only recently become recognized as a widespread problem.

In a new review of previously published studies, researchers from Germany and Denmark took a look at the ways in which noises, such as an airplane passing by or jackhammer digging in the ground, can affect our hearts. Perhaps the most obvious impact of a loud sound while you are sleeping is that it can wake you up. But, even if you don't remember hearing the noise or you don’t physically get out of bed, it can disrupt you in ways you may not realize.

“Noise is not just causing annoyance, but it actually makes us sick,” said Dr. Thomas Münzel, a professor at Johannes Gutenberg University Mainz. “Regardless of where the sound is coming from, if it gets louder than 60 decibels (分贝),it can increase the risk of heart disease.”

When our body hears these noises, it reacts with a stress reaction. In this case, these sudden and unexpected noises cause hormones(荷尔蒙) to speed up and eventually damage the heart. Although the chance that a single noise will affect you is unlikely, it’s the continuous exposure (接触) to the sound that can finally affect you.

“But our heart health isn’t the only cause for concern. Long-term noise may also raise the risk of type 2 diabetes (糖尿病), depression, and anxiety disorders,” he warns. In the future, Münzel plans to examine how noises from cars, planes, and other vehicles affect the brain. But despite the amount or the depth of research he conducts, it’ll take the help of politicians to improve the effect of noise on our health.

“Politicians have to take into account, in particular, the new findings,” Münzel said, “As for aircraft noise and airports, it is important to make new laws and set new lower noise limits that protect people living close by the airport instead of the owners of the airport.”