Apparently the Earth has missed being hit by an asteroid, but our neighbor planet Mars may not be so lucky. Astronomers are watching the object as it approaches the Red Planet, Mars. Many of them are part of the NEO monitoring program. This is the Near Earth Object monitoring program to be exact. The rock, as I like to call it, is about 160 feet wide and would have made quite a crater if it had hit us. It is not at all certain that Mars will be hit by this object, but there is a chance it will be. The last time we saw a spectacular crash of an object into a planet was when Jupiter was hit, not by an asteroid, but by a comet, which is much bigger, named Shoemaker-Levy. When scientists talk about protecting the Earth from meteor hits, that readily admit that if a comet headed this way, there is not much they could do about it. Well this is what hit Jupiter, thank goodness that we have such a giant planet relatively near by to catch many of these things in its gravitational field. Jupiter acts as sort of a buffer. Unfortunately it is not a perfect buffer and some of these objects do get through, but it does help a lot as do the other large planets.

Some scientists actually hope that the rock does hit Mars. Why would anyone want this to happen? The answer is quite simple, this will give them a chance to observe the mechanics of what happens when a planet comparable to the Earth is hit by one of these things. I really don't want to see Mars get disturbed by anything. We haven't even had a chance to send people there to explore it yet, according to NASA. Who knows what is on that planet. It could even be possible that life existed there at one time and maybe it was even intelligent. I would hate to think of a meteor hitting and destroying evidence of past civilizations. What about this, some conspiracy theorists are saying that we will try and steer the meteor somehow to hit mars and use this as an excuse to blow up evidence of past civilizations? Yeah that is a bit far out isn't it? Anyway we have been experimenting with steering asteroids and meteors by putting rocket engines on them. This has been talked about for years since a small change of course when they are far away would mean a big change before they would reach Earth if it was in their path. Since we have done the research, we might be able to steer a rock traveling the other way to a target, such as a planet, so I guess this is where the conspiracy theorists are coming from.

The odds of the objecting hitting Mars have increased to 1 in 75 at last check. When you consider that they were in the tens of thousands at the beginning, that is quite a change, still I wouldn't want to have these odds in Vegas at the card table. The big day will be on 30 January 2008 according to astronomers. That is the day that it will either hit or miss Mars. The asteroid was designated as 2007 WDS when it was discovered on November 20, 2007. As you can see by the date of discovery, there was not much notice that it was coming. Luckily it was not aimed at us, since there would not have been much time to react. As a matter of fact we discovered this asteroid AFTER it made its closest approach to Earth. This certainly doesn't give you much faith in our detection system, does it? I have read that we are only monitoring about 5-10% of the heavens for these objects. It is beginning to look like that figure might be accurate, although I found it hard to believe when I first read it. The asteroid, if it is an asteroid and not a meteor, is traveling at a speed of 27,900 mph. We have been told by NEO that in the next six weeks or so they will be able to refine their calculations and tell us if it is going to hit Mars.

Asteroid Gaspra
Photo Source: NASA/JPL

What will happen if Mars is struck, what will be the result? As near as anyone can figure, it will create a crater about 1/2 mile in width. Some objects have been known to explode in the air and not create craters at all. This is what experts think might have happened in Tunguska in Russia. That is where a gigantic explosion took place. It is believed that a meteoroid or even a small piece of a comet exploded at an altitude of 3-6 miles above the area. No one really knows the exact size of the object and there are all different estimates. What is important is that the force of the explosion was calculated at 10-16 megatons. This makes it over 1,000 times the size of the explosion that devastated Hiroshima, Japan. It is estimated that 80,000,000 trees were blown down and the blast covered 830 square miles. It is believed that the explosion was a 5 on the Richter scale. This just shows us the tip of the iceberg when we try and see what the limit is to a natural disaster. There are things out there in space that could incinerate our planet in a heart beat. It is believed that if Mars is hit, the energy expended will be about 3 megatons.

Some politicians have been urging congress to spend more money to monitor the skies for asteroids, meteors and comets. They want to increase the effectiveness of our detection system. For once I agree with them, much better detection is needed. Maybe a monitoring station in orbit or on the moon might fill the bill or maybe we need one on each side of the planet or on both sides and at both poles. The thing it that it is equally as important, if not more important, to have a viable plan to deal with these things if they are headed towards the Earth. Several plans have been put forward. One is the rocket engine we talked about before. One or more would be placed on the object and then turned on to change its course. If you see the object soon enough, it wouldn't require too much power to nudge it off course. Another option was to erect a solar sail on the rock that would slowly power it off course also. Then there are the various ideas about launching nukes at it. What you don't want to do is break it up so that instead of one piece headed for us we would have hundreds. If you use a nuke it should only be used to force the object off course, not to try and blow it up. Some scientists have though of using lasers to get it to shift course. It is time that we figured out the best method and developed a way to use it.

Most of these objects come from a region at the far end of our Solar System known as the Kuiper Belt. We don't know the exact size of it yet, but it is believed that it extends from the orbit of Neptune, which is approximately 30 AU outward to about 55 AU. AU stands for Astronomical Unit and is equal to the distance of the Earth to the Sun. This works out to about 93 million miles. We know that this region contains up to 200 times as many objects as the asteroid belt that is located between the orbits of Mars and Jupiter. Besides the difference in density between the two regions, there is a big difference in the size of the objects contained in them. It is believed that there are some planet sized objects in the Kuiper Belt. An object discovered recently is believed to be bigger than Pluto, which is no longer considered a planet. Comets that have orbits lasting less then 200 years are thought to come from the Kuiper Belt. Another comet like object called a Centaur is believed to come from there. I guess if we could get rid of the objects in the Asteroid and Kuiper Belts, we would eliminate most of the objects we have to worry about getting hit by.