What would happen if a meteorite hit the earth? Would it destroy our planet, or would it cause some sort of disaster?
Meteorites are pieces of rock from space that fall to the ground. They come in various sizes and shapes. The largest recorded meteorite was found in Russia in 1908 and weighed over 7 tons.
A large meteorite hitting the earth could create a massive explosion. This would result in a huge fireball and a shockwave that would travel around the globe at supersonic speeds. The resulting damage would be devastating.
However, larger impacts are rare, and thousands of tiny pieces of space rock which are also known as meteorites, hit the ground every year. We look at this in closer detail and find out just how often meteorites hit the earth.
What Are Meteorites And How Often Do They Hit Earth?
A meteorite is any piece of rock that comes from outer space. Some meteors burn up in the atmosphere because they are made mostly of gas, while others enter the earth’s atmosphere and break into small pieces.
These smaller pieces then rain down onto the surface of the earth where they become meteorites. Most meteorites are less than 2 inches across and can weigh several pounds. There are three main types: stony, iron-nickel alloyed, and stony-iron.
Stony meteorites contain more than 95% stone by weight and include most of the rocks we see on earth such as granite, gneiss, basalt, quartz, feldspars, and mica.
Iron-nickel meteorites have about 5% metal content and are usually dark grey or black.
Stony iron meteorites are similar to stony meteorites but with higher amounts of iron.
Most meteorites are too small to notice when they land. A few hundred thousand falls hit earth each day, but only one or two make it through the atmosphere intact.
The size of these objects determines what happens when they crash to the ground. Smaller ones will burn up in the atmosphere before reaching the ground, while bigger ones will survive until they reach the surface.
Where Do Meteors Come From?
The first meteorite ever discovered was found in 1750 in Siberia. It was named after its discoverer, Russian scientist Mikhail Lomonosov. He called it “The Stone From Heaven” because he thought it came from heaven. In reality, it was an ordinary piece of rock.
Most meteors come from asteroids. Asteroids are rocky bodies left over from the formation of the solar system. Many asteroids orbit between Mars and Jupiter. When these objects get close enough to the sun, their orbits change so that they move closer to the sun.
Eventually, they cross paths with the earth and either collide with us or pass right by. If they strike the earth, they can explode spectacularly.
Some asteroids are very big. One asteroid, Eros, weighs over 3 billion tons. It has a diameter of about 1 kilometer (0.6 miles). On the other hand, some asteroids are very small. One object, P/2013 R3, is only about 20 meters wide.
Meteorites are often formed when asteroids smash into planets like the earth.
Before this, they are called meteoroids. If a meteoroid survives its journey through the atmosphere and lands on the surface of the earth, it becomes a meteorite.
Sometimes, the collision causes the entire asteroid to melt. Other times, the impact breaks the asteroid into many fragments. These fragments then fly away from the original body. They may even leave behind a trail of debris.
Meteorites are not always visible. Sometimes they appear as streaks of light in the sky. Sometimes they streak across the night sky for hours before disappearing. Sometimes they disappear completely.
The most famous meteorite impact occurred in Siberia in 1908. A large chunk of rock fell from the sky, creating a crater that measured 10 km wide and 20 km deep. It also left behind a trail of destruction that stretched for several hundred kilometers.
Scientists believe that this meteorite originated from Mars, and was travelling at a speed of 40 km/second. It struck the Earth at the height of 50 km above the ground.
When larger meteorites hit the earth, they cause tremendous explosions. These explosions can be seen for hundreds of kilometers around. The force of the blast can shatter windows and blow outbuildings.
Large pieces of the meteorite will remain in the area and can be picked up by people who live nearby. Smaller pieces of the meteorite fall to the ground and create craters that look like giant holes in the earth’s surface.
However, the pieces of rock falling from the sky are not usually the biggest concern regarding meteorite impacts.
What causes more damage and destruction is the shock wave caused by the meteor when it breaks in the atmosphere.
An example of this is the Chelyabinsk meteor which was an asteroid that was the size of a six-story building and entered the Earth’s atmosphere in February 2013 over Russia.
This meteor broke apart 15 miles above the ground but generated a shock wave which would equal a 500-kiloton explosion, injuring 1,600 people.
How Often Do Larger Meteorites Hit Earth?
Although it is estimated large impacts only happen once in around every 5 years, most astronomers can’t predict meteorite impacts, as meteoroids in outer space are usually too small to even detect.
However, even larger events that come from asteroids, and can be tracked in space, are still unpredictable. Fortunately for Earth, 90 -95% of meteors don’t live past the fall through the Earth’s atmosphere to turn into catastrophic meteorites.
This is because a lot of meteorites are believed to stem from comets, and these are much more fragile than asteroids.
Although predicting meteorite events on Earth is almost impossible, there are a couple of different ways of measuring the number of meteorites that manage to hit Earth.
For example, in uninhabited regions such as the Sahara Desert, you can easily locate meteorites on the ground and figure out their dates based on the weather they have gone through.
The meteorites at these undisturbed locations provide scientists with an idea of how many of the space rocks could have hit the Earth over a certain amount of time.
Another way of estimating the number of meteorites hitting Earth is to use satellites. Satellites orbit the Earth constantly, so if one of them detects a meteoroid entering the atmosphere, it can track its path until it hits the ground.
By comparing the trajectory of the meteoroid with the known orbits of the satellite, scientists can estimate the date of the event. Using this method, researchers found that about 2,000 meteorites enter our atmosphere every day.
We hope you have enjoyed reading about meteorites and how often they hit the earth. Remember, the majority of meteorites that reach the Earth are very small, and only a few make it down to the surface.
Most of the smaller ones burn up in the atmosphere or break into fragments.
Larger explosions caused by shock waves are rarer but using uninhabited locations and satellites, scientists and astronomers are constantly figuring out new data to estimate the number of meteorites, large and small, that are hitting Earth every day!
- I Can’t See Anything Clearly Through My Telescope – Help! - April 26, 2022
- Astronomy For Beginners – Getting Started Stargazing! - April 26, 2022
- Are Telescopes Easy To Use? - April 26, 2022