Meteor Impacts





Chances are Good


Meteors are very common throughout outer space. They are being whipped around our solar system in every orbit possible. Normally they are peacefully and serenely floating through space, but one just has to look at the cratered face of our moon or Jupiter’s moon Callisto to see that more than a few meteor’s journeys through space have been interrupted. The earth has been hit before and will be hit in the future, statistics show this. We must detect the meteors a long time before they cross paths with Earth to prevent an impact. The likelihood of a significant meteor impact in the near future is extremely small, but it is still a possibility.
The earth is just like every other planetary body in space in that it is hit by meteors frequently. Most of these meteors are small enough that they burn up in the atmosphere. A NASA FAQ website states that meteorites the size of a basketball strike Earth about once a month, with nearly 75 percent landing in water. These are completely harmless to humans. Larger asteroids with potential for major global environment changes hit once every 100,000 years on average. A NASA Impact Hazard Fact website states that a 2km diameter or larger object collides with the Earth once or twice per million years, producing a global catastrophe that would kill a substantial (but unknown) fraction of the Earth’s human population. This means that a person has about one chance in 20,000 of dying as a result of this type of collision. That same website states that less than 10 percent of the estimated 2,000 or more near Earth objects that are larger than about a half-mile in diameter have been detected to date. All in all, one should be more worried about easier (and higher probability) ways to die in this world like car crashes, diseases, other natural events, and many other possibilities.
Preventing a meteor impact depends on how soon before it hits that we find it. We have the technology right now to alter most meteor orbits away from earth. But if we never discover a meteor intercepting the Earth, these meteor ‘weapons’ are useless. Because much less than half of all near Earth objects are still undiscovered, we most likely will not have any warning before a meteor hits. But, if one of the meteor detection programs actually discovers an asteroid on a collision course, we will probably have many years of warning. In the next few decades, most near Earth objects will be found because any object that is going to hit Earth will swing near our planet many times in its orbit before it hits. So, the warning time is essentially very long or none at all. Even if we only have less than a year warning, and we are unable to alter the meteor’s course, we will still have time to build underground shelters and stockpile supplies for long-term survival. The key to preventing collisions is early detection.
The chance of a large (more than 1 km) meteor being on an intercepting course with the earth in the next hundred years is very small. Consider that we also have a good chance to modify the course of the meteor and the chances of collision are insignificant. The human race is doing the best it can to protect it’s home by striving to discover all the asteroids with orbits near Earth’s. Chances are good that a large meteor impact is not in the near future.




Bibliography: