Chances of Life Surviving Meteor Impact
We will start off with small sized meteoroids. These range from sand size particles to basketballs. These types of meteor strikes occur multiple times a day (hundreds-thousands times a day), and are what you see in the sky as a "shooting star". These obviously are not harmful to life on Earth at all. Unfortunately these are not the only types of meteoroids that strike our planet.
The next and much rarer type of meteoroid that strikes our planet is the medium-large type meteoroids. The size of these would be roughly the size of a car. These types of meteoroids strike our planet's surface and cause a fair amount of damage within the vicinity of the strike zone. There is evidence of a strike like this in Arizona. The crater there is ¾ of a mile wide and roughly 700 feet deep. If this were to happen again, it would not wipe out any life on our planet, but would kill many people and cause large amounts of damage in the area where it hit.
The last type of meteor strike is that of the large scale. These types are kilometers wide and can be either meteoroids or comets. These large objects are what people should be losing sleep over. One a few kilometers in diameter would strike the earth at 50,000 miles an hour and would shake the whole planet. If it hit the ocean it would cause massive, hundred foot tall waves that would go many miles in land wiping out all the popular coastal cities. After the initial shock is over, our planet would be covered by mile high clouds of dust and ash that would block out the necessary sun light. Without sunlight plant life and human life would eventually die off. In this scenario, organisms known as extremeophiles would survive. These are organisms that live deep down in oceans, or in very acidic environments or really hot/cold environments. Extremeophiles don’t require much to stay alive so in this event they would still survive. The one event that would cause a complete extinction of all life on our planet would be like that of the one that caused the formation of our moon. In this event it is believed that an object the size of about Mars, struck our planet. If this were to happen, our planet would get knocked off of its axis, as well as the whole entire surface being turned into hot molten material. All the water would be evaporated and there is no way life would survive after an event of this magnitude.
