Courtesy of NEAR/NASA.

The Why Files is starting to fret about asteroids, comets and other junk from space. We know asteroids and comets can wreak havoc when they strike Earth. Think of it as yesteryear's science fiction -- and today's science fact. According to a presentation at a national scientific meeting, asteroid impacts over the past 10,000 years had a hand in shaping the climate and the nature of civilization itself.

The alarm over asteroids has even reached the tabloids. "The end of the world?" bellowed the cover of the Weekly World News (see "A Message from God" in the bibliography). "Shell-shocked NASA scientists are scrambling to come to grips with a top-secret radio transmission received from the icy vastness of deep space that appears to be a communication from God Himself." An asteroid detected earlier this year -- its threat since discounted by legit astronomers -- appears destined to impact in January, 2022, the World gushed, with the predictable catastrophic consequences. We don't know about that -- and we'd hate to impeach the veracity of our colleagues in the fiber-media, but....

Will you be squashed by an asteroid? Probably not today, probably not tomorrow, but someday, and perhaps soon, a fast-flying rock from outer space could run your account seriously in the red -- along, perhaps, with the rest of civilization. It all depends on whether you believe the optimists or the pessimists in the festering debate about asteroid hazards. As we'll see, both sides use essentially the same facts, but reach radically divergent conclusions.

Doin' the bump
One thing that's no longer in dispute, however: Space jams of the sort we'll be discussing are the only natural events -- save perhaps epidemics -- that could terminate civilization. If you worry about earthquakes and volcanoes, then you gotta at least think about getting rocked by rocks that are ignoring the speed limit.

But hey, just because hardballs from outer space put the dinosaurs (and half the other species on their team) into the cosmic cellar 65 million years back, look at the bright side. A true fastball -- remember -- these objects may cross home plate at more than 15 kilometers per second, could strike out "I want to be a Millionaire" -- and toss the McLaughlin Group from the game for good measure.

A collision with a comet or asteroid would be no soap opera, yet as the world turns, it's continually assaulted by rocks and ice from space. These old and restless objects are dregs from the formation of the solar system, and they orbit through the days of our lives, waiting to slam into New York, maybe looking for a guest appearances on Oprah...

One glance at the cratered face of the asteroid, and you know fast-moving rocks can really ding things up on the bold and beautiful planets and moons in our solar system. None of this destruction is likely to be featured in "America's funniest home videos." Considering the blast, the fires and smoke, the gigantic waves caused by oceanic impacts, the death and the destruction, maybe we should be talking General Hospital meets ER.