Look! Up in the sky! It's a bird. It's a plane. No, it's none of those. It's not Superman, either.
Instead, it's a big asteroid or comet on a collision course with Earth. Impact could mean the end of civilization as we know it, maybe even the destruction of humankind and various other life forms.What's the world to do?
Why, summon the best scientific minds, of course. Then launch a spaceship into outer space carrying nuclear weapons either to blast the asteroid to smithereens or nudge it out of its trajectory toward Earth.
Yes, we know this scenario sounds like the plot of a bad science fiction film. But it's what various astronomers and NASA scientists have been talking about lately. Though laymen may understandably be tempted to snicker, it would be a mistake not to take the experts' warnings seriously. Some parts of their advice, however, are much better than others.
The part that makes sense involves a proposal to set up a new network of telescopes with computerized detectors capable of giving advance warning when a big asteroid or comet is headed toward Earth. The price tag is a relatively modest $10 million, not much to pay for peace of mind. The Earth shows signs of catastrophic space collisions in the dim and distant past. So many asteroids and comets are whizzing around in space that another big collision seems statistically likely. The proposed new telescopes, besides gleaning other interesting information from outer space, could alert the world to an impending collision as long as decades in advance.
What then? Some scientists are talking about starting a big anti-asteroid weapons program. But that would be folly, since scientists still don't know where 97 percent of the asteroids are. Besides, blowing a threatening asteroid into pieces is not a good idea: if the pieces rained down on Earth, they could do as much damage as the original object. Instead, most scientists are convinced it would be better to nudge the asteroid into a different path - and they say it would not take a particularly big bomb to do the job.
Meanwhile, if the demise of the Cold War has left you without enough to worry about, consider the implication of the latest news from the people who study space: Somewhere out there is a huge hunk of hurtling rock with Earth's name on it.