Unless we spend money to spot and prevent asteroids (小行星) now, one might crash into Earth and destroy life as we know it, say some scientists.
Asteroids are bigger versions of the meteoroids (流星) that race across the night sky. Most orbit the sun far from Earth and don’t threaten us, But there are also thousands of asteroids whose orbits put them on a collision course with Earth.
Buy $ 50 million worth of new telescopes fight now. Then spend $ 10 million a year for the next 25 years to locate most of the space rocks. By the time we spot a fatal one, the scientists say, we’ll have a way to change its Course.
Some scientists favor pushing asteroids off course with nuclear weapons. But the cost wouldn’t be cheap.
Is it worth it Two things experts consider when judging any risk are: 1 ) How likely the event is; and2) How bad the consequences ff the event occurs. Experts think an asteroid big enough to destroy lots of life might strik
A. They are heavenly bodies different in composition.
B. They are heavenly bodies similar in nature.
C. There are more asteroids than meteoroids.
D. Asteroids are more mysterious than meteoroids.
Unless we spend money to spot and prevent asteroids (小行星) now, one might crash into Earth and destroy life as we know it, say some scientists.
Asteroids are bigger versions of the meteoroids (流星) that race across the night sky. Most orbit the sun far from Earth and don’t threaten us, But there are also thousands of asteroids whose orbits put them on a collision course with Earth.
Buy $ 50 million worth of new telescopes fight now. Then spend $ 10 million a year for the next 25 years to locate most of the space rocks. By the time we spot a fatal one, the scientists say, we’ll have a way to change its Course.
Some scientists favor pushing asteroids off course with nuclear weapons. But the cost wouldn’t be cheap.
Is it worth it Two things experts consider when judging any risk are: 1 ) How likely the event is; and2) How bad the consequences ff the event occurs. Experts think an asteroid big enough to destroy lots of life might strik
A. It is very unlikely but the danger exists.
B. Such a collision might occur once every 25 years.
C. Collisions of smaller asteroids with Earth occur more often than expected.
D. It's still too early to say whether such a collision might occur.
B
Unless we spend money spotting and preventing asteroids now, one might crash into Earth and destroy life as we know, say some scientists.
Asteroids are different forms of the meteoroids that race across the night sky. Most orbits the sun far from Earth and don’t threaten us. But there are also thousands of asteroids whose orbits put them on a violent coming course together with Earth.
Buy $ 50 million worth of new telescopes right now. Then spend $10 mil]ion a year for the next 25 years to locate most of the space rocks. By the time we spot a fatal one, the scientists say, we’ll have a way to change its course.
Some scientists favor pushing asteroids off course with nuclear weapons. But the cost wouldn’t be cheap.
Is it worth it Two things experts consider when judging any risk are: 1) How likely the event is; and 2) How bad the consequences if the event occurs. Experts think asteroids big enough to destroy lots o
A. It sounds practical but it may not solve the problem.
B. Further research should be done before it is proved to be capable.
C. It may create more problems than it might solve.
D. It is a waste of money because a violent coming course of asteroids with the earth is very. unlikely.
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