I think we have all seen stories where the earth is threatened by a collision with meteors. The last one that comes to mind is "Armageddon", where the entire earth is hit by bigger and bigger meteors until the planet killer, the biggest hunk of rock will hit unless something is done. Well as they say, it was only a movie, or was it? Could we ever find ourselves in the position where large objects were poised to hit the earth? What would we do if such a hit was immenent, would we launch a nuclear missile at the object? Would we warn the people in the area where the object was about to hit to at least give them a chance to get out? Would we even be able to detect all objects that were about to hit the earth?

These are tough questions indeed. The budget for detection of objects that might hit the earth in the U.S. only allows us to watch about 10% of the heavens, leaving a huge gap in the area we have to observe to give us an effective detection system. Everyone knows that the chances of anything large hitting the earth are very slim, or at least that is what most people think. Unfortunately someone should have told this to the people of Finland this month. A huge meteorite hit the northern provence of Aftenpoften Norway with the force of a nuclear bomb. Before this huge rock hit, people watched it as it streaked across the sky, even photos were taken of it. In case the distinction between a meteor and meteorite is unclear, a meteorite is a meteor that reaches the surface of the earth without being completely vaporized.

A crater in Arizona from a previous hit

How did this happen and where did the meteorite come from? Schwassmann-Wachmann 3 was a periodic comet that swung this way every so often. I could be wrong but I think that it appeared about every 12 years or so. This is not so important in the scheme of things. The important part is that the comet began to break up in 1995. In 2006 a large chunk entered earth orbit and broke up into about 30 more pieces. Are there pieces of this comet orbiting the earth? Is the object that hit Norway a piece of Schwassmann-Wachmann 3? Why didn't we try and shoot down this object before it struck the earth? Gee, there are so many questions to answer and so few answers. It seems to me, since I didn't hear of any people dying in the strike area, that we knew it would hit an isolated area and by hitting it with a missile we may have sent the pieces raining over populated areas thus causing more casualities. I like to think this anyway. The truth may be far simpler, it may just be that we either didn't know it was coming or we don't have the ability to hit a meteor.

Typical Comet

When this object hit the ground, the force was so great that it caused a powerful earthquake in the highlands of Scotland. This was another event that didn't receive much news coverage. I guess you need a high death toll before something is considered news worthy. If's funny, for the past ten years or so, we have heard so much about shooting these things down and yet, when we have a reason to try and do it, we do nothing. Where is all that star wars technology we keep hearing about. The military keeps telling us how accurate their anti missiles are and yet when they have a chance to test their capability they don't.

One has to wonder what other hazzards are waiting for us. If there are more fragments of the comet in orbit, will one or more of them come loose and head for the planet? It would be nice to know if we are even watching them if they are there. Should we put more money into our sky watching? It seems to me that if we want to avoid something like this in the future we must at least be able to detect it. Detection is very important as I am sure we all realize. The second thing that we must be able to do is destroy the object. What good is all the detection in the world if there is nothing you can do after you see that big rock heading for earth? The trick woud be not only to destroy it, but vaporize it so that no smaller pieces are created.

Comets are known to split into smaller pieces. About thirty comets have been observed to split. Knowing this, we must keep an eye on comets that pass fairly close to the earth. This is where amateur astronomers come in handy. There are enough of them to keep us posted on anything fairly large heading our way. It is the relatively small stuff that will cause them a problem since it takes telescopic power to spot these objects and most amateurs just don't have the equipment for this. In the end, it is the government's responsibility to make sure that these observations are carried out.