What threats exist in outer space that could affect life on earth?
"do without" = lacking something essential
"If space travelers had to do without fresh water for very long, they wouldn't be able to survive."
"at the drop of a hat" = immediately, willingness to do something without delay
"I'd travel to the moon at the drop of a hat if I had the chance."
A. Listen to the recording and answer the questions.
I've just arrived here in Barrow, Alaska, to bring you live coverage of what appears to be the results of a huge meteorite impact, perhaps the largest in recent history.
The exact location of the impact is unknown, but estimates put it about 20 kilometers south of Barrow based on shock waves felt throughout the region.
Some witnesses say they saw a bright light streaking through the sky, accompanied by a roaring boom, moments before the impact.
A meteorite 10 kilometers in diameter crashed into Earth 65 million years ago which led to the mass extinction of many animal species including the dinosaurs.
In recent years, astronomers have focused more of their attention on the paths of many uncharted space rocks or asteroids floating out there in space.
What are three specific things that world governments can do, individually or collectively, to prevent or minimize the impact of future catastrophes such as huge meteors and asteroids of this kind on a global scale? Use the Internet to research the topic of asteroid avoidance strategies or plans for planetary defense of such events.