To date, more then 120 planets have been found beyond the confines of the Solar System. All of these planets (except for a few disputed ones) are gas giant planets like Jupiter (except for some brown dwarfs that are up to 15 Jupiter masses). One of the more interesting facts is that a good portion of these gas giants orbit very close to their host star, directly oppisite of our Solar System. The theory is that these giant planets "migrated" from the outer parts of these solar systems, pushing the tiny terrestrial planets out of there orbits or even out of there solar systems all together. This raises the question, why hasn't this happend in our solar system? I think I have an answer, the asteroid belt. If you were to go into the heart of the asteroid belt, chances are, you would never even see a single asteroid. And your spaceship wouldn't even feel the slightest tug from anything. But when you look out the asteroid belt in the larger picture, a picture of the whole solar system, the combined mass of the space rocks in the belt would measure several quad-trillion metric tons, making the asteroid belt the secong heaviest of objects in the solar system besides the sun. Do we underestimate the influence the asteroid belt has on our solar system? And with all of those precious ores out there, just how strong is the asteroid belts' magnetic influence on gas giant planets? After all, gas giant have extreamly powerful magnetic fields, could these magnetic fields be pushing against the asteroid belt, keeping the gas giants from moving inward, protecting the inner solar system?

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if our asteroid belt were removed, WOULD the gas giants move closer to the sun?

Ziggy, if all of the asteroids from the asteroid belt were added togeather, the mass would not be much more than about 1/2 the moon. There is a link to solstation.com in the Resources on the Web topic, try going to that site and follow the links to the asteroid section to review this subject.

As for the asteroid belt having any influence on the giant planets, the answer is no. There simply isn't enough mass in all of the asteroids combined to have any influence on those huge planets.

Remember that Jupiter is bigger than all of the other objects in the solar system (except the sun) combined.

And no Starlab, removing all of the asteroids in the asteroid belt wouldn't have any noticable affect on any of the other planets.

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Duane's right Ziggy,

There's so little mass in the asteroid belt that it wasn't even taken into account when the Pioneer and Voyager crafts flew right through without a scratch..

But you raise a very good point and you might be pointing to the wrong source.
Comets might be the culprit that foils Jupiter's plot.

Once thought to be dirty snowballs, it appears they are far more complex with the
latest info from Stardust. Towering pinnacles, plunging craters, steep cliffs and dozens of jets spewing violently..Stardust will land in 2006 with some interesting data.

Comets might be what keeps feeding the interior planets with enough mass which they sweep out from the Kuiper Belt..This plus what they throw at Jupiter themselves, keeping it fed. Their num,bers may have been quite large in the solar systam's early infancy.

I suspect it is they who bring in the iron and drop it in the Sun's corona which
professor Manuel mistakens for being solar in origin. The high ionization of iron
that exists in the corona cannot take place in high density environments. This is why scientists called the highly ionized iron "coronium" when they first observed it.
We could not reproduce it in a lab because the density of Earth's atmosphere is
too high. The Sun's interior is also too high. The only logical explanation I can come up with ( other than incoming stardust itself ) is that comets drag both water
and heavy matter inbound...or they make an exchange of some sort..

Anyway, that's my 2 cents...Take it with a grain of salt. Someone might pitch in a better explanation.

blueshift

I think it should be noted the asteroids in the asteroid belt are not like a barrier. They are so spread out that asteroid-on-asteroid collisions rarely happen.

http://www.spaceref.com/news/viewpr.html?pid=14574

SpaceRef story about Asteroid fragments.

Thought it might be interesting.

http://www.spaceref.com/news/viewpr.html?pid=14563

The ESA move an asteroid Idea is great! Long overdue.

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