The Truth On
Near Earth Asteroids


With all the hype on an asteroid smashing us now thanks to the movies out, I feel I should make it somewhat clear about the truth.

  • Which movie is more realistic?
    Deep Impact is the winner, but because expensive special effects and soundtracks impress more than the reality quotient, Armageddon was more popular. I saw Armageddon..I was impressed by the effects, but it was pretty unbelievable. Deep Impact I have yet to see.

  • So what would really happen?
    Well, it depends on the size of what hit us. I'll give a nice convienient table rather than babble about it.
    Size of BodyRate of ImpactImpact Over LandImpact Over Water
    Up to 200 yards1 to 10 per centuryMay explode in the air, causing a multi-megaton blast that flattens the area below for hundreds of miles. Could cause extensive local damage, but no lasting enviromental effects.If it stays intact and hits near shore, a small tidal wave could occur.If in deeper waters, there are probably no effects.
    200 yards to 1 mile in diameter1 every 10,000 to 1 million yearsCould make a crater up to 10 miles wide, with devastation on a national scale around the impact area. World wide environmental effects, likely resulting in large scale famine, and economic depression.A worldwide tidal wave that could flood all land below 200 feet above sea level. (Including New York, Washington, and most of Holland.)
    1 mile to 10 miles in diameter1 every 1 million to 100 million yearsThis will create a crater up to 100 miles across. The dust cloud from impact would comtaminate the atmosphere, resulting in a "nuclear winter" that could last several years. World wide famine and economic crisis.A giant tidal wave, with catastrophic effects on most coastlines. Low lying nations worldwide wiped out.
    Over 10 miles in diameterLess than 1 every 100 million yearsLoss of most forms of life on Earth as a result of prolonged "nuclear winter" and consequent ice age.Ditto.


  • Where do asteroids come from?
    Mostly from an enourmous ring lying between Mars and Jupiter, known as the asteroid belt. Every now and then, an asteroid will wander out of it's orbit, and head toward the inner solar system, caused most likely by the gravitational pulls of Mars or Jupiter.

  • What's the closest one has come?
    The closest near collision we have had in recent history was in 1994, when the body known as 1994 XL1 passed us within 60,000 miles. This is 4 times closer than the Moon.The object was 30 feet across.

  • So what's being done about this?
    Frankly, not very much. Truth is, more people work in a single McDonalds restuarant than are employed to monitor asteroids.

  • But didn't one of these things wipe out the dinosaurs?!
    Maybe. That's just one of many theories of the dinosaurs extinction. However! Off the coast of Yucatan, Mexico, there lies a 110 mile wide crater. This might possibly be an explanation for the extinction of the dinosaurs.

  • Are we gonna die?
    Well, the odds of being killed by an asteroid are 1 in 5,000, which is higher than the odds of being killed in a plane crash. But mainly this is because a plane crash would be very very centralized, while an asteriod is over a large area. But if one was found to be approaching Earth, right where you live, there's a pretty high risk of death.

  • Can't we stop them somehow?
    Not really. Smallish ones could probably be shattered with nuclear weapons, but even in small ones there's a risk for debris pummeling the Earth. There are also ideas on landing mini rockets on one to redirect it's course, or detonating a nuclear weapon near the asteroid to redirect it but not shatter it. You'd need at least a 5 month advance warning though.

  • Well. I prefer the movie version.
    Don't we all. It makes reality so nice and pastel colored that we don't worry about it at all.