December 12

How Was the Asteroid Belt Formed

The asteroid belt is in the middle of our solar system. Did you ever wonder how it got there? Well imagine this, large amounts of gravity, asteroids trying to fuse together but blasting apart into pieces. Or another theory is that a planet blasting into many pieces to form the asteroid belt. Here is the last theory, imagine Jupiter drifting toward Mars, then coming back out scattering asteroids in every direction. Now let’s look at the facts!

Asteroids and the Asteroid Belt

Now, you’re probably thinking, “What is an asteroid?” Well an asteroid is a small rocky object orbiting a star. Most asteroids in the asteroid belt are left over from the solar nebula. The asteroid belt is made of a lot of asteroids orbiting our Sun. The asteroid belt is located between Mars and Jupiter. One last fact is that the mass of the asteroid belt is 4% of the moon. Now you know all this, let us move on.


The stuff that is grey is where the asterod belt is located.

Why is the Asteroid Belt Not a Planet?

As you probably know, gravity is used to make moons, planets, galaxies, stars and so on.   Too little or too much gravity doesn’t allow these things to form. Now let’s talk about Jupiter and two ways it affects, or affected the asteroid belt. Jupiter’s mass is the greatest of any planet in our solar system. Jupiter’s pull is so strong, most scientists believe it is one of the main reason the asteroid belt is not a planet. Especially in the asteroid belts early stages, when it tried to form a planet but even if they got close to each other and hit they would be blown into even smaller pieces.

Another theory is that Jupiter, in it’s early stages, drifted towards Mars, but when it came back to where it is currently it left the debris in the middle, now the asteroid belt, making the debris in the middle fling around. Also it left the debris with so much energy, everything was crashing into each other. Gravity affects a lot of things but does it have to have affected the asteroid belt? Well some scientists think not. Read on to find out about another theory.

 Could the Asteroid Belt Have Been a Planet?

Do you know about the hypothetical planet Phaeton? Well let me tell you about it. Some scientists argue that the asteroid belt is left over from a planet that was destroyed, and somehow made a bunch of asteroids, well it’s something along those lines. Others say that Phaeton would have been formed. Those scientists say that the turnings from protoplanets into planets was disturbed by Jupiter’s gravitational pull. That is one of the last MAIN theories about how the asteroid belt was formed. Naturally there are many more theories I could not include in this article. That is because nobody knows the exact way the asteroid belt was formed. All we have are theories.

What Do You Think?

Now that you have some of the main theories what do you think? Which theory do you believe in? Do you belive the theory that it is all up to Jupiter’s gravitational pull? Do you think Jupiter came in toward Mars then moved out and made too much energy? Or do you think the asteroid belt is left over from an exploded planet? Remember nobody knows exactly how the asteroid belt was formed. Maybe you will be the one to find the exact theory!

The asteroid belt now

Just for fun, this is a type of video. This is what it means : This video shows the progression of NASA’s Near-Earth Object Wide-field Survey Explorer (NEOWISE) investigation for the mission’s first four years following its restart in December 2013. Green dots represent near-Earth objects. Gray dots represent all other asteroids which are mainly in the main asteroid belt between Mars and Jupiter. Yellow squares represent comets.

Photo credits:

By Mdf at English Wikipedia – Transferred from en.wikipedia to Commons., Public Domain, Link

By NASA/JPL-Caltech/PSI – Catalog page · Full-res (GIF), Public Domain, Link