"But there is no roof over Earth. Thoughout the eons our planet has been hit by many asteroids and comets large enough to do damage: plenty of big rocks are still out there now. As Zahnle (planetologist) added, 'A day will surely come when the sky is torn apart with a power that beggars the imagination. It's happened before. Ask any dinosaur, if you can find one. This is a dangerous place.'"
Question: Can you explain the bold print sentences to me, please?
ANSWER: I'll start with the author of the statement: Kevin Zahnle is a scientist with NASA. He has written journal papers on the impact of comets and asteroids upon Earth. Asteroid #7860 is named Zahnle. There are thousands and thousands of asteroids in an area between Mars and Jupiter. Their have been several movies made about comets and asteroids hitting Earth.
A day will surely come means one day it will happen when the sky is torn (to tear or rip) apart means the sky will seem divided with a power (comet or asteroid) that beggars the imagination means a physical force and energy that defies perception. It's happened before means it has occurred in the past. Ask any dinosaur, if you can find one is the author's sardonic humor. We can't find any dinosaurs today because they are extinct. The author is saying they became extinct about 65 million years ago due to a giant impact of an asteroid. (That's a theory.) This is a dangerous place means Earth is a place that can cause harm or loss, but the author means Earth is unsafe due to his belief that a comet or asteroid will one day again hit the Earth.
Now to paraphrase: One day it will 100% happen that an asteroid or comet will come through our atmosphere (sky) with an energy force (because of size and speed) that we cannot believe it is actually happening. We have a theory that it was an asteroid that caused the disappearance of the dinosaurs, thus this planet is a hazardous place.
Notes: that beggars the imagination; the word beggars is a transitive verb, meaning only that it requires a direct object, which is imagination.
Other uses: It beggars description. (It cannot be described.) His theory is so outrageous as to beggar belief. (His theory is so preposterous that it is unbelievable.) Her beauty beggars description. (Her beauty is undescribable.) "Ambiguous Bill"
