题型:阅读理解 题类:模拟题 难易度:普通
四川省遂宁市2020届高三上学期英语第三次联考试卷
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.
There are many international organizations which work to save and protect endangered species (物种) and natural environment. If you would like more information about any of the organizations listed below, you can write to the addresses given.
Friends of the Earth (FOE) campaigns on a range of problems including rainforests, the countryside, water and air pollution and energy. Friends of the Earth International Secretariat P.O. Box 19 199 1000 G. D. Amsterdam The Netherlands | Greenpeace uses peaceful but direct action to defend the environment. It campaigns to protect rainforests and sea animals' slop global warming and end pollution of air, land and seas. It also opposes nuclear (核) power. Greenpeace International Keizergracht 176 1016 DW Amsterdam The Netherlands |
BirdLife International is an organization which works to save endangered birds all over the world. BirdLife International Wellbrook Court Girton Road Cambridge CB3 ONA | England WWF-World Wide Fund For Nature is the world's largest private international organization for the protection of nature and endangered species. Information Officer WWF International Avenue du Mont —Blanc 1196 Gland Switzerland |
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