Posted on 04/05/2006 7:53:38 PM PDT by KevinDavis
A FIFTH terrestrial planet may once have orbited between Mars and Jupiter. Although gravitational disturbances would have sent the planet hurtling into the sun or out into space long ago, traces of this long-gone world may still be visible in part of the asteroid belt today.
Recent simulations have suggested that the gas giants of our solar system formed with circular orbits but moved into their more elongated paths about 4 billion years ago – 700 million years after the solar system formed. While the gas giants were in circular orbits, rocky planets should have formed in stable orbits out to a distance of 2.2 astronomical units (1 AU = 1 Earth- Sun distance).
However, there are no planets between Mars, which lies at 1.5 AU from the sun, and Jupiter at 5.2 AU. That puzzled Sean Raymond of the University of Colorado in Boulder and John Chambers of the Carnegie Institution in Washington DC. "There's room for another planet between Mars and Jupiter," says Chambers. "Given that planets formed everywhere else, why couldn't another planet have formed there?"
The researchers modelled what would have happened in that region, and found that a planet about the size of Mars could have formed 2 AU from the sun and remained stable there until the orbits of the gas giant changed.
(Excerpt) Read more at eurekalert.org ...
It's an old question since Ceres and the other big asteroids were noticed. Some think that Mars may have been part of the missing planet system, a moon of a bigger planet.
Of course, we all know why...but I am not saying it!
Is this the modern version of the Snipe hunt?
Sounds like the theory supported by Richard C. Hoagland.
Not saying that he is wrong (it is, after all, a theory) but well, still, whenever he's on C2C and talks about Mars, one of the theories he constantly brings out and of course, supports is the exploded Planet theory in which Mars was a moon of.
It was Van Flandern, RCH's one time partner in space speculation. But the idea was around long before Art Bell made his first radio.
There is not enough mass in the asteroid belt. Jupiter played a large part in the prevention of the asteroids from forming even a small moon like object.
I could have sworn they would blame a Rove conspiracy to eliminate that "missing" planet. Didn't someone in a recent DUFU say President Bush was a threat to other planets too?
No, it is not a theory, it is, at best, a hypothesis, and at worst pure speculation.
Scientists use the word "theory" in a very specific way that is often confused by laymen.
We're going on a planet hunt.
We're going to find a big one.
I'm not afaid. Are you?
We're looking out to space.
It sure is high.
It sure is wide.
Well, there's nothing over there.
Nothing over there.
Nothing out there.
Hey! Wait! I think I see something!
Quick! Everybody run!
Right. Could be that. The probe that brought back comet tail material is showing materials that took considerable heat to form. Mineralization, which might indicate a degree of planetization. An exploding planet seems overly melodramatic.
All of the planets have elliptical orbits, thanks to Johann Kepler, but Neptune's is very close to being circular, and it's one of the gas giants, so I don't understand the point about the gas giants having elongated orbits.
The moon is heavily cratered, and so is Mercury, and it looks like earth is, too, although erosion and other action has obliterated a lot of the obvious earth craters. There was a lot of big stuff out there at one point.
Nothing wrong with the exploding planet hypothesis other than the fact it would take the energy output the Sun generates for about 20 hours to explode a planet the size of the Earth and prevent it gravitationally reforming, and there is no known mechanizm in a planet that can do that.
Not to mention there is not enough material. LOL!
However, that law does not fit all planets and is pretty suspect.
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