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maflynn

macrumors Haswell
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May 3, 2009
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I always enjoy science shows about space and our solar system. Many of them go into detail about how the solar system was formed and each time, it leaves me with the same question.

The planets were formed by gas/dust/rock particles being attracted to each other and growing. Initially slow due to the small amount of gravity, but over the course of time, getting larger and larger and pulling more and more matter to form planets.

Yet why isn't the asteroid belt in between mars and Jupiter, the Kuiper belt, or ort cloud not forming planets?
 
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I always enjoy science shows about space and our solar system. Many of them go into detail about how the solar system was formed and each time, it leaves me with the same question.

The planets were formed by gas/dust/rock particles being attracted to each other and growing. Initially slow due to the small amount of gravity, but over the course of time, getting larger and larger and pulling more and more matter to form planets.

Yet why isn't the asteroid belt in between mars and Jupiter, the Kuiper belt, or ort cloud not forming planets?

"The asteroid belt between Mars and Jupiter is thought to be left over from a planet that was unable to form due to the gravitational influence of Jupiter or the remains of a planet that was destroyed in a collision"

https://www.reference.com/science/asteroid-belt-between-mars-jupiter-48cfa6a4216c7f65
 
I always enjoy science shows about space and our solar system. Many of them go into detail about how the solar system was formed and each time, it leaves me with the same question.

The planets were formed by gas/dust/rock particles being attracted to each other and growing. Initially slow due to the small amount of gravity, but over the course of time, getting larger and larger and pulling more and more matter to form planets.

Yet why isn't the asteroid belt in between mars and Jupiter, the Kuiper belt, or ort cloud not forming planets?
Since the Death Star blew it up, the mass from that planet is travelling away from the blast at its core. At the same time the gravity is pulling it together. So it just stays the same as one force is cancelled out by the other.
 
"The asteroid belt between Mars and Jupiter is thought to be left over from a planet that was unable to form due to the gravitational influence of Jupiter or the remains of a planet that was destroyed in a collision"
That makes sense, so Jupiter is preventing larger asteroids from forming which in turn will turn into planetoids and planets.

What about the Kuiper belt, and oort cloud? Both of those are far away from any major gravitational forces that could conceivably interrupt planetary creation. In fact, its been estimated that with the discovery of the Kuiper belt, they found many planetoids larger then pluto. Why has the planet creation seemingly stopped there?
 
I always enjoy science shows about space and our solar system. Many of them go into detail about how the solar system was formed and each time, it leaves me with the same question.

The planets were formed by gas/dust/rock particles being attracted to each other and growing. Initially slow due to the small amount of gravity, but over the course of time, getting larger and larger and pulling more and more matter to form planets.

Yet why isn't the asteroid belt in between mars and Jupiter, the Kuiper belt, or ort cloud not forming planets?
Maybe they are but at a rate that is hard for us to detect. I imagine the time to go from dust to a planet is a hugely long time.
 
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Maybe they are but at a rate that is hard for us to detect. I imagine the time to go from dust to a planet is a hugely long time.
No question that intersellar events are on a time scale that dwarfs humanity, but my argument against that is, the other planets. The sun is 4 billion years old, and in those intervening billions of years, other planets formed (and maybe re-formed) All things being equal, since we had 8 planets (sorry pluto) all forming around the same time, it stands to reason that something is not working the way it did for those planets.
 
What about the Kuiper belt, and oort cloud? Both of those are far away from any major gravitational forces that could conceivably interrupt planetary creation. In fact, its been estimated that with the discovery of the Kuiper belt, they found many planetoids larger then pluto. Why has the planet creation seemingly stopped there?
Everything initially was much closer to Sun, once the large planets formed they threw all those object to the outside on weird orbits (Oort) or slowly migrated with ice planets (Kuiper). Planet formation doesn't take place because the material density is very low, you have like a tenth of earth in Kuiper belt, and maybe couple times of Earth mass in Oort - but this is over a vast distance and irregular orbits.
 
"The asteroid belt between Mars and Jupiter is thought to be left over from a planet that was unable to form due to the gravitational influence of Jupiter or the remains of a planet that was destroyed in a collision"

https://www.reference.com/science/asteroid-belt-between-mars-jupiter-48cfa6a4216c7f65
Possibly not..


https://advances.sciencemag.org/content/3/9/e1701138

The asteroid belt contains less than a thousandth of Earth’s mass and is radially segregated, with S-types dominating the inner belt and C-types the outer belt. It is generally assumed that the belt formed with far more mass and was later strongly depleted. We show that the present-day asteroid belt is consistent with having formed empty, without any planetesimals between Mars and Jupiter’s present-day orbits. This is consistent with models in which drifting dust is concentrated into an isolated annulus of terrestrial planetesimals. Gravitational scattering during terrestrial planet formation causes radial spreading, transporting planetesimals from inside 1 to 1.5 astronomical units out to the belt. Several times the total current mass in S-types is implanted, with a preference for the inner main belt. C-types are implanted from the outside, as the giant planets’ gas accretion destabilizes nearby planetesimals and injects a fraction into the asteroid belt, preferentially in the outer main belt. These implantation mechanisms are simple by-products of terrestrial and giant planet formation. The asteroid belt may thus represent a repository for planetary leftovers that accreted across the solar system but not in the belt itself.

Astronomy papers tend to be posted in full on the Arxiv preprint server, so we laymen really do not have any excuse for not keeping up with the latest research
 
Possibly not..
Possibly yes ;) (I mean except for the plant collision thing - everybody knows that the only known asteroid belt which formed after planet destruction are the remains of Alderaan). This is just one model, out of multiple ones, pretty much contradicting 30+ years of research and it wasn't widely adopted as the leading theory, because all the others assume large initial mass and depletion, discussing rather how that depletion may have happened.
 
There were also more planets when the solar system was formed but a lot of those smashed into each other. The Earth is said to have collided with another object and that is what formed our moon.
 
No question that intersellar events are on a time scale that dwarfs humanity, but my argument against that is, the other planets. The sun is 4 billion years old, and in those intervening billions of years, other planets formed (and maybe re-formed) All things being equal, since we had 8 planets (sorry pluto) all forming around the same time, it stands to reason that something is not working the way it did for those planets.
I like the local gravity explanation.
 
Your question withstanding, you have to consider a lot of what we see is very old. Take that black hole from a month ago into consideration. It might not even be there now. Or it may be larger or smaller. Who knows. It lives in M87. Which is 55M light years away. What researchers took to be able to construct and image and temperature readings were 55M years old.

As for your question... Many theories exist. I remember wasting an entire summer thinking about that as a child. But the aforementioned is what's fascinating about space. You're looking at live history.
 
I guess you have to consider the SS as a work in progress, not a static, finished system - eventually Saturn will lose it's rings, Mars and Neptune will gain rings as some of their moons break apart, Mercury is very likely to be flung into the sun or out of the solar system altogether! Eventually the Asteroid belt might coalesce back into a planetesimal like the one it's likely to have started out as. It might also end up disappearing by chance bumps and passes flinging the material in all directions out of orbit.
 
Since the Death Star blew it up, the mass from that planet is travelling away from the blast at its core. At the same time the gravity is pulling it together. So it just stays the same as one force is cancelled out by the other.

This is all I needed to read to fully understand the power of the Death Star which in turn answered the question completely and left nothing unanswered! Well played... Well played.
 
I guess you have to consider the SS as a work in progress, not a static, finished system - eventually Saturn will lose it's rings, Mars and Neptune will gain rings as some of their moons break apart, Mercury is very likely to be flung into the sun or out of the solar system altogether! Eventually the Asteroid belt might coalesce back into a planetesimal like the one it's likely to have started out as. It might also end up disappearing by chance bumps and passes flinging the material in all directions out of orbit.
I can’t but help picture what you are speaking of on an expanded scale as if the solar system is not large enough. I’ve said this before, but it is images of the galaxies that give me a sense of complete wonder, especially when you zoom in on the Earth and experience it’s natural settings. To think there could be a billion places like this scattered among stars!

751F1D7E-6DB8-46ED-89C3-35C5264A3B18.jpeg

It’s hard to believe a place like Earth can be taken for granted, and most of us do as a matter of routine. This is such a gem, that it seems, at least not worthy of the self-described advanced species on the planet to trash it, and not cherish it because of our biological needs and desires. No, not starting a debate, just a statement of deep felt emotions. :)
 
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I can’t but help picture what you are speaking of on an expanded sale as if the solar system is not large enough. I’ve said this before, but it is images of the galaxies that give me a sense of complete wonder, especially when you zoom in on the Earth and experience it’s natural settings. To think there could be a billion places like this scattered among stars!


It’s hard to believe a place like Earth can be taken for granted, and most of us do as a matter of routine. This is such a gem, that it seems, at least not worthy of the self-described advanced species on the planet to trash it, and not cherish it because of our biological needs and desires. No, not starting a debate, just a statement of deep felt emotions. :)
Yep, not just a spec geographically, but in terms of time the existence of all our civilisations is also a brief blip!
 
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