Out from nowhere, a ball of fire can emerge and hit the Earth like a speeding bullet resulting in an explosive collision releasing as much energy as tens of thousands of megatons of TNT! Results? An extinction-level event that can wipe out most or all of life forms on this blue orb that we call home! What can cause this? Yes, you are right! An asteroid! Looming somewhere deep in the darkness of our very own Solar System, these asteroids are messengers of eminent doom! The question is, ‘when’? No one knows but someday, mankind will have to face this threat. So, let us today learn 15 fascinating facts about asteroids and find out what they really are and what they are capable of! Are you ready?
Asteroid Facts: 1-10
1. Asteroids are amazing celestial objects that hang in our Solar System. There is a whole reservoir of these objects hanging between Mars and Jupiter. How many of them are there? Millions of them! This reservoir is known as asteroid belt.
2. Asteroids are not new or sudden creations. They are old, very old! In fact, they are as old as our planet Earth or any other planet in our Solar System. These asteroids share a common birth with our planets. About 4.6 billion years ago when our Solar System was forming, objects would collide with each other, sticking together to form larger objects and eventually forming planets and satellites. Some of these objects broke apart on collision and failed to gain mass. These unfortunate ones are the asteroids!
3. As far as chemical composition of asteroids is concerned, they are home to wide range of minerals, metals and other substances. Asteroids that were formed by breaking away from some planets inherit a similar chemical composition as the planets.
4. The chemical composition of asteroids undergoes changes while orbiting the sun. This happens because of various chemical reactions that take place. Asteroids that are far from the sun usually have silicate rock composition. Those that are close usually are carbonaceous.
5. There are metallic asteroids present as well. They are mostly made of iron but may also contain other metals like platinum, gold, palladium, iridium etc. There may be some asteroids that have half metallic and half silicate composition.
6. Asteroids often collide with each other. Upon collision, smaller ones can break and end up as dust on the larger ones. This dust is known as regolith. It is not necessary that asteroids will collide only with other asteroids. Any object that crosses their path can collide.
7. Asteroids are pretty dangerous. Collision between asteroids can throw them out of their orbits and set them on a collision course with planets. Earth is not immune to such impacts. As a matter of fact, collision between asteroids and planets shape the very fabric of a planet. Earth as experienced numerous asteroid collisions ever since it birth.
8. Collision of asteroids with planets is known as impact event. An impact event can shape the atmosphere of a planet and change its climate. These impact events can be extinction-level events. For instance, it was an asteroid that led to the extinction of dinosaurs some 65 million years ago.
9. Not all asteroids that are on collision course with earth will collide on Earth. Most of them are destroyed in upper atmosphere. Some burn out and sprinkle on earth in form of cosmic dust. These are usually very small asteroids. However larger asteroids make it through the atmosphere. Some are just big enough to cross the atmosphere and explode at 10 to 15 kilometers above the surface. Some are quite big and eventually land on earth’s surface.
10. Those asteroids that crash directly on earth’s surface leave a crater and destroy everything in the surrounding area. The extent of damage caused will depend on the size of the asteroid. A single very large asteroid is capable of wiping out life from entire earth. Those that do not crash but rather explode a few kilometers above the surface are also capable of causing immense damage because of the heat and shockwave produced by the explosion.