The asteriod belt between jupiter and mars!! ...did it used to be a planet long long time ago,..why is it there?

because they are in a stable part of our solar system. And so like any other stable part in contains stuff, in that sence that they contain verry little mass. All combined they have less mass then the moon.
It was never a single planet and it never well be.

It's there because the gravity of Mars and Jupiter acting on it in opposite directions prevented it from coalescing into a planet. It wouldn't have been a very big planet either.

Conveniently there are many asteroids in the Belt which are insanely rich in useful ore-bearing rocks, including titanium, nickle, gold, platinum, iron etc. Any group/company able to exploit them would get incredible rewards, and since each [suitable] asteroid contains hundreds of billions of dollars worth of metal (at todays prices, naturally there would be a huge deflation if the Belt were exploited) the company can plough huge sums of money into Asteroid mining R&D and still make a profit at the end.

yet that is only a hypothesis!!!.. while astronomical theories are still shaky when it comes to planet formations and star birth's in nebula clusters...the possibilty of a comet or planet straying off to a collision course with something out there cannot be ruled out!!!,..again this is merely a hypothesis on my behalf!!

http://www.time.com/time/archive/pre...939902,00.html
http://www.nasa.gov/mission_pages/viking/

What is only a hypothesis? you are not being at all clear.

Remember that the solar system is still littered with small bodies orbiting all over the place. A recent announcement, following discovery of an asteroid on an inclined orbit at one of Neptune's Torjan points, suggested that Neptune may have a suite of associated asteroids whose bulk is greater than that of the asteroid belt.

Another theory is that two planets did at one time exist in the region of the Asteroid belt, but that one's orbit was perturbed enough by Jupiter to cause it to crash into the other. Most of the debris ended up in wild orbits (non circular, highly elliptical), bringing them into proximity with the inner planetary orbits, where they then collided with those planets, causing extensive cratering. Much, however, hit the sun.

The small percentage that by chance remained in a nearly circular orbit then became the asteroid belt. The moons of those planets might still remain, as spherical asteroids (four of them, I believe). All of that took place early in the solar systems' history, circa 4-5 Billion years ago. Clearly, meteors are chunks of solidified molten iron-nickel, etc. that are remnants of larger bodies that underwent gravitational stratification during a molten phase. The best potential source for those meteors is debris from the asteroid belt. Much smaller ones (shooting star kind) are also often comet dust.

You might wish to read an earlier post of mine describing an alternative theory to solar system formation, in which numerous astrophysicists have postulated that the inner planets were once large (but not as large as Jupiter) gas-ball giants, which lost their Hydrogen and Helium due to early OB stars high UV output in the neighborhood in earth's early history, leaving the rocky inner cores (which we also know exist in Jupiter, for example). Even Jupiter, under this theory, lost 2/3rds of its Hydrogen, and its moons were depleted of their Hydrogen/Helium blankets.

Recent astronomical evidence supports this alternative theory, in that large gas-ball-giant planets have now been found in orbits close to their suns.

Walter,

That sounds like an interesting theory, I'll have a look at your earlier posts!..Thanks!!

Wouldn't the lost matter have hit the sun. I heard that when 0.5 earth masses of heavy elements hit the sun even 5 billion years ago, we could still detect it

Anything hitting the sun would be vaporized/ionized. The additional iron/nickel/silicon/oxygen would be a tiny drop in the bucket to what was already there in the sun.

>> The asteriod belt between jupiter and mars!! ...did it used to be a planet long long time ago,..why is it there?

From MY calculations it appears that the asteroid belt is in the right place for a once was planet

Mars appears to be suffering the same fate

Why.... well the planets are receeding from the Sun, and Jupiter is a little closer that it should be because of its size and back up (the gas 4)
so the inner planets are being squashed against Jupiter's magnetic bloch wall...... leading to disintergration, Mars is next, then maybe Earth long term

all IMO and drawn from the math

And heavy elements have had plenty of time to sink to the core. We have limited detection ability below the surface.

Why are they doing this?
Show us your math or forever hold your peace.

So are you Bode or Titius?

Actually I don't believe that because of the heat transfer from the core to the sun, the metals wouldn't sink.
And I don't believe they would leave with the solar wind (not all of it)
I got this information from a pdf that said according to Murray (No ID who that actually is but it's from 2001). He said that at least 0.5 earth mass is needed to fall into a G type star to be detectable.

Anyway I don't believe that the asteroid belt was ever a planet. But some of those bodies like vesta ar more dense then they should be. Meaning they originally came from somthing larger.
I believe that some of those asteroids were originale on a protoplanet, and kickt of by large impacts and then ended up at more or less stable lagrane points. Later when most of the solar system was formed the left the stable points and moved away yusing planetairy fly by's to get into a further orbit, or yust impacted the planet.
I'm not sure if this is correct but it would explain why the asteroid belt has so little mass, and is so wildly spread out.

Orcot, I believe this may be the relevant paper:

Murray, N.; Chaboyer, B.; Arras, P.; Hansen, B.; Noyes, R. W.
Stellar Pollution in the Solar Neighborhood
The Astrophysical Journal, Volume 555, Issue 2, July 2001

We study spectroscopically determined iron abundances of 640 solar-type stars to search for the signature of accreted iron-rich material. We find that the metallicity [Fe/H] of a subset of 466 main-sequence stars, when plotted as a function of stellar mass, mimics the pattern seen in lithium abundances in open clusters. Using Monte Carlo models, we find that, on average, these stars appear to have accreted ~0.5 M⊕ of iron while on the main-sequence. A consistency check is provided by a much smaller sample of 19 stars in the Hertzsprung gap, which are slightly evolved and the convection zones of which are significantly more massive; they have lower average [Fe/H], and their metallicity shows no clear variation with stellar mass. We argue that our Sun is likely to have accreted a similar amount of iron; in this respect, most systems resemble ours rather than the currently known extrasolar planetary systems. These findings suggest that terrestrial-type material is common around solar-type stars.

The complete paper is available here:
http://www.journals.uchicago.edu/ApJ.../53091.web.pdf

thx I hope it wasn't to difficult to find

Approximately forty five seconds.