1 . An experimental cleanup device called RemoveDEBRIS has successfully cast a net around a dummy (仿真的) satellite, imitating a technique that could one day collect spaceborne garbage.
The test, which was carried out this week, is widely believed to be the first successful demonstration of space cleanup technology, experts told CNN. And it symbolizes an early step toward solving what has already been a critical issue: junk in space.
Millions of pieces of junk are turning around in orbit, the result of 50 years of space travel and few regulations to keep space clean. At orbital speeds, even a small bit of paint crashing with a satellite can cause critical damage.
Various companies have plans to send thousands of new satellites into low-Earth orbit, already the most crowded area.
The RemoveDEBRIS experiment is run by a company and researchers led by the U. K.’s Surrey Space Center and includes Airbus, Airbus-owned Surrey Satellite Technology Ltd. and France’s ArianeGroup.
Guglielmo Aglietti, the director of Surrey Space Center, said that an operational version of the RemoveDEBRlS technology would cast a net that remains fastened to the main satellite so the debris can be dragged out of orbit. It could target large pieces of junk, including dead satellites up to 10 meters long.
The RemoveDEBRIS satellite will conduct a few more experiments in the coming months, including testing navigation features that could help guide the satellite to a specific piece of debris.
Jonathan McDowell, an astrophysicist at the Harvard-Smithsonian Center for Astrophysics, said the success of this week’s experiment was exciting, but he cautioned against “over- publicizing” it.
There are still enormous barriers to clear before operational cleanup tasks are underway, he said, and the most discouraging is figuring out how to fund such projects.
Aglietti, the Surrey professor who helped lead the RemoveDEBRIS project, said “The challenge will lie in persuading the relevant authorities to sponsor these tasks.” Aglietti said he hopes RemoveDEBRIS will conduct a few cleanup tasks per year, targeting the largest pieces of junk in the most crowded orbits.
1. What is the use of the RemoveDEBRIS satellite?| A．Demonstrating space technology. |
| B．Imitating a developing technique. |
| C．Collecting wastes existing in space. |
| D．Symbolizing great progress in space. |
| A．By throwing a net to take the junk from orbit. |
| B．By fastening it to the main satellite tightly. |
| C．By dragging satellites up to 10 meters long. |
| D．By targeting large pieces of junk carefully. |
| A．Accomplish. | B．Support. | C．Oppose. | D．Provide. |
| A．The RemoveDEBRIS Project Is Perfect |
| B．How RemoveDEBRIS Is Invented in the Lab |
| C．Why the RemoveDEBRIS Satellite Is Invented |
| D．Satellite Collects Space Junk for the First Time |
2 . Eating too much fatty food, exercising too little and smoking can raise your future risk of heart disease. But there is another factor that can cause your heart problems more immediately：the air you breathe.
Previous studies have linked high exposure (暴露) to environmental pollution to an increased risk of heart problems，but two analyses now show that poor air quality can lead to heart attack or stroke (中风) within as little as a few hours after exposure. In one review of the research, scientists found that people exposed to high levels of pollutants (污染物) were up to 5% more likely to suffer a heart attack within days of exposure than those with lower exposure. A separate study of stroke patients showed that even air that the U. S. Environmental Protection Agency (EPA)considers to be of “moderate” (良好) quality and relatively safe for our health can raise the risk of stroke as much as 34% within 12 to 14 hours of exposure.
The authors of both studies stress that these risks are relatively small for healthy people and certainly modest compared with other risk factors such as smoking and high blood pressure. However, it is important to be aware of these dangers because everyone is exposed to air pollution regardless of lifestyle choices. So stricter regulation by the EPA of pollutants may not only improve environmental air quality but could also become necessary to protect public health.
1. The text mainly discusses the relationship between ________.| A．heart problems and air quality |
| B．heart problems and exercising |
| C．heart problems and smoking |
| D．heart problems and fatty food |
| A．relatively high | B．extremely low |
| C．relatively low | D．extremely high |
| A．Eating fatty food has immediate effects on your heart. |
| B．The EPA conducted many studies on air quality. |
| C．Moderate air quality is more harmful than smoking. |
| D．Stricter regulations on pollutants should be made. |
| A．inform | B．persuade |
| C．describe | D．entertain |
