Dec 03 2008
Asteriods
It is undeniable that some time in the future an asteroid will be on the course to hit the planet that we call Earth and home. It may be true that it is very unlikely to occur, but it is also true that when it does, it will have the chance to destroy the planet as we know it. We need to be aware of this because it is possible that in our lifetime this could happen. However when we look at it, there is a chance of survival even if we are blind to the fact. Earth has been struck by asteroids before and humans still inhabit it, although if we wish to preserve the way of life that we know, we all deserve to know a little more about asteroids.
Quite a few movies in our lifetime have been made about the topic of an asteroid hitting the Earth and destroying it or at least life on the planet. However most of them depict situations that are usually impossible to imagine ourselves in. This is because they usually include one or a few heroes who save the planet at the very last possible second, often sacrificing themselves in the process. However those are movies and are made like that for our entertainment. Though behind these Hollywood creations there is sometimes a shred of truth.
At this current moment we do not know of any asteroids on a collision course with Earth. A few years back however there was an announcement about an asteroid that was on a course to collide with Earth in the year 2028. However the mathematics were proven to be flawed and we now know that the asteroid will completely miss the Earth entirely. The fact is, the chances of us, Earth, being hit by an asteroid is extremely small. This is because the universe is so enormous and by comparison the Earth is so small. Most of the asteroids in our galaxy are contained in the asteroid belt. However in this belt there is so much more empty space than asteroids that there is a very small chance of something breaking loose and flying directly towards the Earth without missing.
Asteroids capable of causing a disaster on a global scale must be about a kilometer in diameter, asteroids this big impact the Earth approximately every 100,000 years on average. Large objects such as comets, impact even less frequently, like every 500,000 years on average. Those are just averages however, it’s not like we’re going to be hit by an asteroid every 100,000 years and a comet every 500,000 years on the dot. That’s just preposterous.
On January 30, 2008, an asteroid passed within 540,000 kilometers of Earth. This seems like an extreme distance but it you take into account the size of the galaxy that’s not too far away. The fact is, most people don’t even know that happens, unless you happen to be browsing “Science Daily” on the day it occurred. This is because scientists knew about it and knew it wasn’t heading on a path to collide with Earth. Asteroids are usually seen from hundreds of thousands of miles away. Therefore if an asteroid is seen on a path to Earth it can most likely be stopped without much of a problem. Since they are so far away a slight push from chemical rockets planted on its surface could alter its course drastically. An effort to stop an asteroid from hitting the Earth would most likely be an effort of large nations working together.
Asteroids are constantly flying by the Earth and around it, but at the distance they travel their path never comes close to hitting Earth. This is because of the scale of the universe. Also the amount of asteroids in the solar system is great but there are not too many that can cause a catastrophic event. If you were to take all the asteroids in the asteroid belt and put them together they would make a mass less than half the size of the moon. However asteroids can come out of anywhere and not just the asteroid belt. Therefore the skies are constantly being watched for asteroids on a path to Earth.
Another interesting thing to touch on is the topic of Jupiter, as both a shield for Earth and also a source for concern. Until late 2008, Jupiter was thought of as a shield for the Earth from asteroids and also comets. This is because it has such a large mass, over twice the mass of all the other planets in the solar system combined. This caused large asteroids to be drawn to it and was the major cause of the asteroid belt. Also when a comet or other object would enter our solar system, Jupiter would draw it close and sling it out before it had the chance to impact the Earth. However it’s downside is that it also prevents objects from leaving the solar system and recently has began sending asteroids closer to the sun which alters their course closer to Earth. So while it protects Earth and has before from asteroids, it may become more detrimental to us in the future.
With the future in mind, if an asteroid is coming to hit the planet there is no reason to panic. This is because there are many different ways to stop the collision of an asteroid and many of them are easy since the course of an asteroid can be altered so easily. Therefore if there are ever asteroids approaching the Earth or coming within a close range of the Earth the mass population might not even be told about it till a plan has been worked out. This may be to reduce panic which is probably a good thing. All in all asteroids will always be there in the universe and the possibility of them hitting the planet will be there also. However it’s not like an asteroid on a path to Earth will result in imminent death.
What we really need to realize is that it’s not a matter of if an asteroid hits the planet; it’s when an asteroid hit’s the planet. Asteroids are not all accounted for and even if they are and their orbit’s are mapped out they eventually interact with other objects in space, or the sun can heat them in certain ways so that they gain small thrusts, and change their courses on their own. In 2007 experts in fields ranging from planetary experts to nuclear weapons engineers gathered to discuss some options. Many were similar to the “deflect the asteroid” method. However one method was to attach a “tugboat” to the asteroid and pull it off course. The “tugboat” would use an ion engine instead of a chemical engine to propel itself. The engine has about the thrust of a piece of paper resting on your hand, but over a long period of time, say 10 years, it can significantly move the asteroids course.
In conclusion, asteroids are a real threat to Earth and life that resides upon it. However it’s not like we’re cave men with sticks and rocks. We are humans with advanced technology and ideas. From what I discovered researching this essay, I believe we don’t have anything to worry about as far getting hit by an asteroid out of the blue. However the skies must be watched so that we can act accordingly if an asteroids on a course to hit Earth is discovered.
