Some Information On Our Asteroid Belt

Wanted to talk about our solar system's asteroid belt in this thread, due to some things I've read posted in various threads here and there on ATS over the past half year or so.

I've seen a lot of statements like the following:

"The asteroid belt was a planet that was destroyed."

"Comet (insert name here) is going through the asteroid belt."

"The (insert celestial body here) going through the asteroid belt could cause impacts or fling asteroids towards Earth with it's gravity."

I'll touch on on these, but first let us look at a picture:



Most of us should remember being taught in school about the solar system, that the asteroid belt lays between the orbits of Mars and Jupiter. Normally we are presented with a image such as the one above, showing the belt's position.

Unfortunately, this type of visual image does a bit of damage in that it gives people, especially those that only have a passing knowledge of astronomy, a mental image that our asteroid belt actually looks like a very thick, densly populated area of floating rocks.

Hollywood doesn't help in this are either. Say the words "Asteroid Belt" and it can conjur up images like what we saw in Star Wars: The Empire Strikes Back:



These are extreme exaggertations of what the belt looks like. Even the Wikipedia doesn't help. Visual representation of the asteroid belt is much more accurate, but again, people with only a passing knowledge of astronomy do not undrestand the scale of the picture being shown. Here it is:



Wiki Source

It looks like swarms of bees. However, one must realize the distance at which the image is being shown and the scale of the objects.

Most of what you are seeing, you would not be able to see. That is, the majority of asteroids are so small, that the dots that are representing the asteroids, are much to big. However, the creation of this image requires using dots large enough for you to see.
The area of space in between Jupiter and Mars is around 1,849,500,000,000,000,000 square kilometers. The largest of the asteroids is Ceres at only 900 km wide.
So far around 100,000 asteroids in the asteroid belt have been found. And they are spread out in that vast number of square kilometers up there.

Here is a good example of showing how isolated many of them are, and not groupted together like we see in images representing them, or like in the Star Wars movie. This is a animated image of the asteroid known as Ida as the space probe Galileo approached it.
As you can see........or rather, as you can NOT see a bunch of other asteroids around it. Instead, we see it as a isolated pice of rock:



To give you a good analogy, imagine having 100 coins. Now dump them on a table in front of you. They look closely packed together. Imagine that each coin is a asteroid.
Now, to give you a better sense of the actual asteroid belt, take those same coins, and spread them out so that they cover the city of New York.

Mmmmmm. They aren't as bunched together now, are they? That's the distances we are dealing with.

Now the reason that is important is to cover those statements I see about other objects 'plowing' through our asteroid belt and colliding with the asteroids.
The chances are there of course, and are much higher than else where in the solar system......but considering the distances between asteroids in the belt.......you have a better chance of winning a power ball lottery.

Realize too that space is 3 dimensional, and that not all objects fall within the plane of the solar system. Most of the asteroids in the asteroid belt do fall within the solar plane. However, some objects, like many comets, may have a highly inclined orbit, meaning they do not travel within the plane of the solar system. This decreases their chances of hitting an asteroid even more so.

Let's talk about where the asteroid belt came from.

Please realize that when we talk about things like "Where the planets come from." or the asteroid belt in this case, we are not dealing with fact, but instead are dealing with theories and models.
This is because: unless you have a time machine and can go back and actually SEE how it was done, we can't really say that it's a fact.

Since 1802, the idea that the asteroid belt was from a planet that had exploded or broke apart from a collision has been suggested. Of course it wasn't until 1850 that the term "Asteroid Belt" was first used, but as far back as 1802 after looking at Ceres and Pallas (2 of the largest asteroids), that the idea came into being.

However, over time, this theory has fallen deeply out of favor, and with good reasons:

1) The total mass of all the asteroids in the asteroid belt if put together would equal only 4% of the mass of our moon. That's small...very, very small. Way too small to be a planet.

2) Chemical make up of the asteroids in the asteroid belt varies quite a bit. Because they vary so much, it's hard to explain if they all came from a common source (such as they all made up a planet). If the asteroid belt had been formed from the explosion or collision of a planet, the chemical make up of those asteroids would be very close in nature. Instead, they vary all over the place, suggesting that they did not come from a common point.

The generally accepted theory is that the asteroids in the asteroid belt formed right where you see them, but were unable to form into a planet because of Jupiter's influence on them.

Asteroid Belt Formation

So how often do these asteroids "bump" into each other, possibly sending smaller fragments on a collision course with the Earth?

Here's an answer to that very question:

The high population of the asteroid belt makes for a very active environment, where collisions between asteroids occur frequently (on astronomical time scales). Collisions between main-belt bodies with a mean radius of 10 km are expected to occur about once every 10 million years.

Please note some words in the above quote that I've bolded. Frequent on a astronomical time scale is 10 million years. So not as often as one might think. And that's with larger bodies reaching up to 10km in size.

Okay, well let us assume the worst. Let us say objects did collide (asteroid to asteroid, or a comet actually does smack into one), and it just happened to do it right so that it means a possible collision for Earth. How long before it get's here?

Answer: tens of millions of years.

as it typically takes many tens of millions of years for an asteroid to reach a resonance with Earth and then collide

Source

Does this mean the fireballs that many have been talking about of late didn't come from a impact of objects from our asteroid belt?

Why no, it is quite possible that they have come from there. But if they did, it was something that happens a very long time ago.

That means that even if say comet ISON were to hit an asteroid (very low chance of it doing that), it would take tens of millions of years for any possible fragments to intersect with Earth's orbit.

Hope this thread is informative and helps anyone interested.

So like if we had a time machine we could observe the collisions of asteroids which would hit earth ten or more million years in the future?
Great OP...!

Nice,very impressive ...I can't really reply.I wish I could do cool threads like this

reply to post by eriktheawful


Thanks eriktheawful, that was a very enjoyable read.
With out a doubt, your hypothesis is every bit as valid as the others I have considered.
Maybe even more so.

Keep the good work going, as I look forward to your future threads.

Thanks for taking the time to assemble the great images and share them as well.

S&F

reply to post by eriktheawful


A brilliant, educational post, thank you !

Question?...are those rocks being cavitated through space?...meaning is space as thick as water

Great post, erik-the-wonderful.

On the topic of asteroid collisions, here's a video with the incredibly hot Amy Mainzer talking about "collisional families"



Seems like the fragments of the smashed asteroids stay roughly in the same orbit around the sun as the asteroids that produced them. Some eventually do fall to Earth, and we can recognise that they resulted from colisions, if the recovered meteorites have fractures or microscopic diamonds in them.

Also worth remembering that there have been a number of spacecraft sent through the asteriod belt now to the outer planets. Pioneer, Voyager, Cassini, Galileo, New Horizons, etc...
None of them had any collision avoidance system.
All of them made it through without being smashed up.

Good post!

And when they do collide..............

Hubble Sees Suspected Asteroid Collision

February 2, 2010: NASA's Hubble Space Telescope has observed a mysterious X-shaped debris pattern and trailing streamers of dust that suggest a head-on collision between two asteroids. Astronomers have long thought that the asteroid belt is being ground down through collisions, but such a smashup has never been seen before.

The object, called P/2010 A2, was discovered by the Lincoln Near-Earth Asteroid Research (LINEAR) sky survey on Jan. 6. At first, astronomers thought it might be a so-called "main belt comet"--a rare case of a comet orbiting in the asteroid belt. Follow-up images taken by Hubble on Jan. 25 and 29, however, revealed a complex X-pattern of filamentary structures near the nucleus

I have seen very compelling evidence that there was a planet....that exploded!
Mars shows the scars from that event. Not here to argue but just to state there are allot of holes in the theory "well the most popular and excepted theory" you have put forth. I am an electric universe advocate which makes allot more sense than the current story< cause it is just a theory not fact. both theories that is..
EXPLODING PLANET and a great video on the subject..a must see
Thunderbolts of The Gods

Originally posted by SarnholeOntarable
Question?...are those rocks being cavitated through space?...meaning is space as thick as water

In order for something to cavitate it needs a medium, like water that you suggested.

However space itself is empty. Hence the usage of the word "Space". Space can have things in it (IE planets, stars, asteroids, etc).

The reason that an object can cavitate in water (or atmosphere) is because it's matter that is surrounded by more matter that is less dense than the object.

Originally posted by paradiselost333
I have seen very compelling evidence that there was a planet....that exploded!
Mars shows the scars from that event. Not here to argue but just to state there are allot of holes in the theory "well the most popular and excepted theory" you have put forth. I am an electric universe advocate which makes allot more sense than the current story< cause it is just a theory not fact. both theories that is..
EXPLODING PLANET and a great video on the subject..a must see
Thunderbolts of The Gods

edit on 26-5-2013 by paradiselost333 because: (no reason given)

I don't have a problem if someone wants to favor one theory over another. They are theories because they have not met the criteria to be fact through the scientific method.

Theories have different levels of supporting evidence. The more supporting evidence one theory has, the more it becomes "favored" among scientist.
For example the asteroid belt has more supporting evidence that it formed as individual asteroids, than the theory of a planet that was broken up (by collision, etc).

That is the fun thing about theories. One day someone could find evidence that supports the idea of the asteroid belt having come from a single planet breaking up, and the supporting evidence is much stronger than the current accepted theory. That theory would fall from favor and the single planet theory would become the popular, most accepted one.

Or a completely new theory could emerge.

What does bug me is when someone presents something that is theory as fact.

the currant popular theory is that the main asteroid belt is a failed primordial proto-planet Accretion disc, the spectral data shows that a large sum of the material is aged back to the formation of our system and there are some inconclusive traces that some of this may be extra-galactic. it is suggested that the high orbital velocity of the belt has prevented it to clump and form a Planetesimal

Originally posted by paradiselost333
I have seen very compelling evidence that there was a planet....that exploded!

If it was a planet, then where did it all go?

The total mass of the asteroid belt is estimated to be 2.8×1021 to 3.2×1021 kilograms, which is just 4% of the mass of the Moon.

Originally posted by alfa1

Originally posted by paradiselost333
I have seen very compelling evidence that there was a planet....that exploded!

If it was a planet, then where did it all go?

The total mass of the asteroid belt is estimated to be 2.8×1021 to 3.2×1021 kilograms, which is just 4% of the mass of the Moon.

In truth, it's thought that the asteroid belt when it formed did actually have about the same mass as the Earth. A lot of people may want to jump on that and say: See? Planet sized mass!

The problem is, as alfa1 asked: Where did all that mass go?

The current mass of the asteroid belt is only 4% of our moon. That's a huge drop in mass to go from Earth mass to only 4% of the moon's mass.

Computer models show that within the first 1 million years of forming, the majority of this material was ejected due to gravitational perturbations from Jupiter.

This is based upon the Nice Model which involves the outer planets migrating to their present orbits.

Thanks for the informative thread. It is hard to even conceptualize the vastness of space. Even the rings of Saturn, which appear to be a jumbled up mass of stuff everywhere but is large enough that we are able to punch probes right through them from Earth. Which is insane when you think about the distances involved there.

I was thinking about this yesterday. When watching the movie Contact and Ellie was traveling through the wormholes and stops in view of the nebulae. She was talking about how they shoulda sent a poet. Anyhow, that area of space looks like chaos. But it is only a matter of scale. If she had taken off straight towards its center, she woulda encountered nothing but vast, open space.

Same with the center of galaxies. They look crazy, but still just mostly empty space.

S&F

Originally posted by alfa1

Originally posted by paradiselost333
I have seen very compelling evidence that there was a planet....that exploded!

If it was a planet, then where did it all go?

The total mass of the asteroid belt is estimated to be 2.8×1021 to 3.2×1021 kilograms, which is just 4% of the mass of the Moon.

The same place all the matter goes when a nuclear bomb explodes.

It radiated away as energy and subatomic particles.


I believe in the planet theory myself. That is was an inhabited planet. And the inhabitants were much like us on Earth. They were in constant conflict with each other. Always at war over resources. Then they had one final battle, where they used the most powerful nukes, and triggered their whole planet to go into meltdown. All we see are some parts of the crust that blew off and separated from the main explosion too quickly to fuze into the giant melting core that evaporated into light.

The reason the rocks are of different compositions, is the same reason rocks are of different compositions right here on Earth, and we mine different minerals in different parts of the globe. It's proof that there was a planet there, much like ours, with a varying composition across the surface, that the inhabitants could extract various diverse deposits to use in their technology, just like us.

The planet explosion makes more sense that planet collision also, because all the remaining material stayed in about the same orbit.

I go with the planet explosion, induced by a highly advanced civilization, and suspect that we on earth are the remnants of that original race of beings. The "ark" came to earth, and two by two the living things were brought here to repopulate the solar system, after the devastating war.

reply to post by eriktheawful


1) The current mass of 'belt' ... key word. To assume it wasn't a destroyed planet is an equal amount of assumption based on this point. For starters:
a) you assume that over the course of time, most of the mass remained
b) you assume that most of the mass of theoretical destroyed planet would have stayed in orbit when destroyed

2) isn't the chemical make up pretty varied everywhere? I mean, earth isn't a one trick pony is it? This also includes the assumption that most of the mass of the planet stayed and spread out through the belt, not ejected, pulled, pushed, etc during the crisis that caused the destruction


Now you speak of using a time machine to know the truth of the matter ... same can be said for the 'theory' that collisions only happen once every 10 million years. You can't just assume that, without also assuming a lot of other stuff as well ... that you knew the mass and quantity (which is not full known now) of the belt over the course of billions of years, which cannot be known. We can track and educated guess all we want, but we don't know how much might have been swallowed up by gas giants, sun, kaiper belt, ejected, hit inner planets, etc. Who can claim fact that Pluto or the moonlike objects in the belt are not ex-moons of a deceased planet?

It is all guess work. Some theories may sit better with you than others, or may have what seems like better evidence for (though skewed because we like to view things in terms and ideas we understand and relate to) ... but little proof. There are even theories and formulas that suggest there 'should' have been a planetary object, that relate to the spacing rather accurately of our current planetary bodies.

Again, the theoretical need of tens of millions of years to line up with earth, while probable, is still yet a probability ... we can use your PowerBall™ example with this ... millions of people play and lose regulary, but many still win every year. Just because your chance of getting hit by lightning is small, doesn't mean it won't happen. I mean the impact site of a lightning strike is infinitesimally small in comparison to surface area of the earth. Getting the right numbers in power ball is extremely small ... fact is, when the impact hits, it just might get the perfect shot, and it head directly towards us.

I'm not doom saying either; it is just one of the probabilities. I don't have a 5 mile deep bunker for it. But I don't dismiss it as a possibility in pure speculation.

It also doesn't mean, that if ISON hit something, it cannot hit earth before 10 million years, it very well likely could hit, soon, or never ... so stating something matter of fact, is usually bad, especially when you are playing percentages. Even a 0.000001% chance of something happening, is a chance, and you may feel safe betting against it; it is still an invalid statement to state it clearly that it can't, when it clearly can.


We have just as much chance of being blindsided by something we don't know about.

What is to say that our progress through the galaxy itself, and our collision with random matter ... or the galaxy's progress through the universe, and random matter that may be in its path. Highly unlikely, but still not impossible. The scale of objects we'd need to see is quite small, not good for picking them out. Our sun makes a great blind spot as well.

All we can do is continue to plot what we find, and hope for the best of luck and chance.

But, I cannot rule out any of what you propose is false, nor do I find it concerning either. Worry not about what you cannot change. I also cannot rule out there might have been a planet tucked in between Mars and Jupiter. I can put different weights on its probability until either we can use a time machine, or the off chance another civilization out there exists, happened to record it, and could show us history of our solar system we don't know ... but not holding my breath for either of those.

I have an open mind, and no need to use closed ended statements of my opinions as if they are fact in matters we will probably never know with certainty. The true history and formation of the asteroid belt is one of those things in my humble opinion.

I think an important point to note is how much matter Earth absorbs from space on a continuous basis.

en.wikipedia.org...

Around 15,000 tonnes of meteoroids, micrometeoroids and different forms of space dust enter Earth's atmosphere each year.

Earth has been sweeping space for a couple of billion years, and we are still pulling that much matter from space.

Granted, our solar system is moving around the galaxy at an tremendous speed, and our galaxy is traveling through space at an even higher speed, so in essence, we never return to a space that we once occupied, but one would think all this space debris would be what is contained in our heliosphere. Maybe not? How much stuff is out there floating around between solar systems and between galaxies.

Considering this, I question how accurate the claim on how much matter there is in the asteroid belt.

reply to post by FreeThinkerIdealist


Great post.
Something you touched on that I would reiterate is that we don't really know the total mass of the belt. We discover new asteroids all the time.

Our sciences, while the best model we have, are far from perfect, and often we fall victim to our own vanity in these matters. IE, "we have been mapping the cosmos for a few decades now and in such feel adequately informed to twll you exactly how it all works."