The Asteroid Belt

[sothisrising]

Okay, I heard some theory that the Earth formed at the asteroid belt and was smacked by something big and moved closer to the sun leaving behind the asteroids. <br /><br />The counter to this theory is that the asteroids never formed a planet because of Jupiter's gravity. That assumes Jupiter was a huge planet before the asteroids failed to form a planet. I dont see the logic in that, I'd think planets closer in form first since they're in a more dense part of the nebula. <br /><br />Is it true some asteroids show evidence of "differentiation" as if they were part of a planet? I understand astronomers do believe the Earth was hit by something big in the past, maybe ~4 billion years ago. Is it logical the Earth suffered such a collision and remained in the same orbit?

 

[qso1]

Sothisrising:<br />Okay, I heard some theory that the Earth formed at the asteroid belt and was smacked by something big and moved closer to the sun leaving behind the asteroids.<br /><br />Me:<br />I'm no expert and I'm sure its possible but IMO, not probable. For one thing, there should be a trail of objects leading to the asteroids, and while I realize there are earth orbit crossing and/or NEOs, I don't know if anyone has investigated if they form an identifiable trail to where the asteroids would have been coming out of the Earth. To my knowledge, nobody has and probably because the NEOs don't show signs of trailing from Earth in a way that would suggest this collision scenario.<br /><br />The asteroids never becoming a planet makes a bit more sense to me anyway but for reasons not related to Jupiters presence or absence.<br /><br />Sothisrising:<br />Is it true some asteroids show evidence of "differentiation" as if they were part of a planet? I understand astronomers do believe the Earth was hit by something big in the past, maybe ~4 billion years ago. Is it logical the Earth suffered such a collision and remained in the same orbit?<br /><br />Me:<br />I'm not sure evidence of differentiation is something that can be verified. We only have a few examples of asteroids we have actually imaged and judging by the shapes, I see know way that anyone can determine based on what little info we have on asteroid shapes, that some asteroids resulted from planetary collisions. What larger asteroids exhibit, such as Ceres, is roundness that may be related to objects becoming more rounded as they get past a certain size threshold.<br /><br />Despite the comments I made about the inability to determine asteroid origins based on shapes, There seems to be only two ways they came about, as objects that never formed into planets, or objects resulting from impacts.<br /><br />As for Earth specifically, I would think the planet would be somewhat mishapen if it survived impact with a large body th <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[nexium]

There are many hypothesis floating around. Generally it is thought that many collisions occured (one of them forming Earth's moon) about 4.6 billion years ago, and that big collisions have been very rare, the last 4.5 billion years. Large orbit changes can result from large impacts, but they typically make orbits more eliptical, while many small impacts circularize. To me it seems more likely that Earth moved farther from the Sun.<br />It is generally thought that a planet could not form at the asteroid distance because of the gravity of Jupiter, But the origin of the asteroids are likely diverse, some arriving from beyond the solar system, a few the result of collisions with Earth, and proto Earth. Our sun may have been hot enough to melt the smaller and closer atreroids = differentiate, about 4.6 billion years ago with the help of numerous collisions. It is therorized that Earth was once molton, so likely Mercury, Venus, and Mars were also molton briefly and thus differentiated. Neil

 

[agnau]

Regardless of the past of the asteroid belt, I wonder if anyone has tried to simulate drawing many these rocks into close proximity to see if a single sphere might form from their collective gravity? Is it possible to create an additional terrestrial planet or two out of the asteroids that would not be tidally ripped apart by Jupiter?

 

[vogon13]

All put together, the debris in the asteroid belt would be smaller thatn earth's moon.<br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>

 

[MeteorWayne]

"Sothisrising: <br />Is it true some asteroids show evidence of "differentiation" as if they were part of a planet? "<br /><br />Asteroid samples we have on earth show that some differentiation has occurred on asteroids. For example, the Canyon Diable meteoroid, which created Meteor Crater in Arizona was an object of almost pure Iron-Nickel. This is roughly the same as the earth's core. For this to get to earth, an asteroid must have been large enough to melt from gravity and radioactivity, with the Iron and Nickel sinking to the core. Then the object must have been smashed apart in an impact, with a piece of the core whacking us.<br /> Glad we weren't there 49,000 years ago when it hit. What a bang it must have been!<br /> Meteor Wayne <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[Boris_Badenov]

It has been theorized that all the asteroids found on Earth came from as few as 4 & as many as 30 parent bodies. <div class="Discussion_UserSignature"> <font color="#993300"><span class="body"><font size="2" color="#3366ff"><div align="center">. </div><div align="center">Never roll in the mud with a pig. You'll both get dirty & the pig likes it.</div></font></span></font> </div>

 

[neomortalgirl]

Just curious have there been any missions to the asteroid belt to see if there is any connection with Earth?

 

[heyscottie]

But what do you mean by "connection with earth"?

 

[MeteorWayne]

There have been missions to explore asteroids in the past, but none AFAIK to the asteroid belt. One is coming up (Dawn).<br /><br />There really isn't much of a connection to earth other than they are made from more or less the same material that created the solar system, and once in a while the earth get's whacked with a piece of material from there. See Chixalub, and Meteor Crater. <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[3488]

The Jupiter bound Galileo Spacecraft encountered the silicate main belt asteroids 951 Gaspra & 243 Ida.<br /><br />The Near Earth Asteroid 433 Eros bound NEAR/Shoemaker spacecraft encountered the main belt Carbonaceous asteroid 253 Mathilde.<br /><br />So we already hove some decent close up images of 'permanent' main belt asteroids.<br /><br />Yes, crazyeddie is correct: DAWN will hopefully orbit the very large asteroids 1 Ceres & 4 Vesta , with a chance that the giant main belt asteroid 2 Pallas may be closely encountered, amongst a few other smaller main belt asteroids.<br /><br />I am curious too. What do you mean by connection to Earth??<br /><br />Andrew Brown. <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>

 

[neomortalgirl]

The reason i ask about a connection with Earth is that i came accross a theory that Earth or another planet may have existed there billions of years ago. The theory was that there was a collision that shattered half of this larger sized planet forming part of the asteroid belt and the rest became Earth. I know its far fetched but so far i haven't been able to find any information to disprove the possibility. Why has the Earth taken so long to settle out into a regular pattern with ice ages? I know about the carbon bacteria that changed the balances of oxygen in the atmosphere, but why is the main form of life carry a mineral that is rare on this planet? Is it possible that a collision could have left bacteria? Also a collision could be a drastic enough change to cause the reaction needed for life. I just don't feel that the time frames quite add up, if we were always in this particular orbit around the Sun. Also could Pluto have once been a moon of Saturn? If you seen my last question i posted my main hobby is to study the Ancient past ,it really fascinates me the knowledge they had about our solar system. There were cylinder seals found, depicting the planets we know today discovered before we knew the ones that existed beyond our naked eye.

 

[MeteorWayne]

So many errors, so little time...<br /><br />The theory that a planet existed in the asteroid belt is very unlikely from a dynamical point of view. Jupiter has strong influence in that part of space, separating and controlling the positions and orbits of the asteroids, basically preventing a large enough mass to accumulate into a planet (look up resonance).<br /><br />For the same reason, it's darn near impossible for a large object from there to wind up here.<br /><br />You assumtion that the earth has taken long to settle into a regular pattern of ice ages isn't true. Ice ages are driven ( with influences and feedback from the properties of the earth at the time) by changes in the eccentricity and precession of the earth's orbit (driven by the mass distribution of the solar system (Jupiter, Saturn, Uranus Neptune, and a little bit of leftover rubble) and pure Newtonian and Einsteinian orbital mechanics, and the obliquity (tilt) and precession ) top spinning effect) of the earth's pole of rotation.<br /><br />What mineral do bacteria carry that is rare on our planet. Surely you are not referring to Carbon?<br /><br />What planets were on the seals you mention?<br />All the planets, (even Neptune, though it's marginal) are naked eye planets, if you disregard Pluto, which I do.<br /><br />There is virtually no chance that Pluto was a moon of Saturn....can't get to it's current orbit from there. Possibly it was once a moon of Neptune, but even that is unlikely. <br /><br />You need to read up on the math of the solar system.<br /><br />MW <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[astroguard]

<b>neomortalgirl</b> wrote:<br /> <br /><i><font color="yellow"># i came accross a theory that Earth or another planet may have<br /># existed there [between Mars and Jupiter] billions of years ago.</font>/i><br /> <br />There are a couple of different ideas about that:<br /> <br />Planet V Hypothesis<br /> <br />Phaeton Hypothesis<br /> <br />An on-site study of the main-belt asteroids will be necessary to determine whether they are remnants of some larger body rather than planetisimals that failed to accrete.</i>

 

[MeteorWayne]

In general, the mathematics of the solar system are very advanced compared to your first 2002 reference. The scenario outlined is much more unlikely than was calculated at that time.<br /><br />As for Phaethon (by the way, the name of the parent asetroid to December's Geminid meteor shower), it's basically the same idea, from a Wikpedia article. Not a reliable source.<br /><br />MW<br /> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[astroguard]

<blockquote><font class="small">In reply to:</font><hr /><p>As for Phaethon (by the way, the name of the parent asetroid to December's Geminid meteor shower), it's basically the same idea, from a Wikpedia article. Not a reliable source.<p><hr /></p></p></blockquote><br />It's not always possible to cite a <i>"reliable"</i> source for certain topics, such as the Phaethon (thanks for the spelling correction) hypothesis. If you can recommend one, please do.

 

[3488]

I think that these are more reliable sources, that MeteorWayne was referring to.<br /><br />MeteorWayne is correct, I too have noticed inaccuracies in Wikipedia.<br /><br />I would take what MeteorWayne says about this as said. He is an authority on this<br />sort of thing.<br /><br />Asteroid 3200 Phaethon.<br /><br />Asteroid 3200 Phaethon Physical Data.<br /><br /> JPL 3200 Phaethon info.<br /><br />Andrew Brown.<br /> <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>

 

[astroguard]

Andrew, none of your links refers to the "Phaethon Hypothesis" under discussion. Please refer to the discussion thread.

 

[MeteorWayne]

"Most astronomers today, however, believe that the asteroids in the main belt are remnants of the protoplanetary disk, and in this region the incorporation of protoplanetary remnants into the planets was prevented by large gravitational perturbations induced by Jupiter during the formative period of the solar system."<br /><br />"Today, the Phaeton hypothesis has been largely discarded by the scientific community, after it was superseded by the accretion model"<br /><br />"The theory is most popular today with fringe scientists and creationists "<br /><br />Need more be said?<br /> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[astroguard]

<b>MeteorWayne</b> asked:<br /> <br /><i># Need more be said?</i><br /> <br />Yes, of course it does. You should know that science is not a matter of majority rule. When we look at the history of what <i>"most astronomers"</i> believed, we see a long list of mistakes, and this belief may turn out to be one of them. The snide statement about <i>"fringe scientists and creationists"</i> is a clue to the prejudicial nature of the dismissal of Olbers' conjecture. Now you tell me whether more need be said.

 

[MeteorWayne]

Well please demonstrate how you can show the mainstream view is wrong in this case.<br />I'm all ears for what YOU have to say. <br /><br />By the way, I certainly agree with you that the answer to this and many<br />other questions about the early history of the solar system are contined within the asteroid belt and Kuiper belt, both frozen records from that time. <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[3488]

I would like to hear it too MeteorWayne.<br /><br />AFAIK, the influence of the young Jupiter may also had stunted the growth of Mars,<br />leaving Mars being rather small (second only to Mercury).<br /><br />Andrew Brown. <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>

 

[yevaud]

*Sigh*<br /><br />No credible way for a large, planetary body to exist where the Asteroid Belt is now; none. The simple presence of the Kirkwood Gaps shows the perturbative effects of Nearby Jupiter. Further, the amount of total mass spread among all of the asteroids is far insufficient to be any large sized body at all (1/10,000 the mass of Earth total).<br /><br />That was concensus following many years, decades, of examination, observation, and tedious theorizing. Majority rule in the sense you mean wasn't and isn't present here.<br /><br />I must add, scientists are as a rule generally <i>pragmatic</i>. Say what you will about the "dismissal" (which is NOT what occurred) about Olber's Paradox. But funny thing...the theory surrounding it does fit our observations; I can hardly claim any other alternate idea will fir the bill of goods. Can you? <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[astroguard]

<b>MeteorWayne</b> wrote:<br /> <br /><i># Well please demonstrate how you can show<br /># the mainstream view is wrong in this case.</i><br /> <br />I recommend that we obtain more and better information about main-belt asteroid formation (as from the Dawn mission, for example) before committing ourselves to the most popular ad-hoc explanation. Now you please demonstrate how you can show the mainstream view is *right* in this case.

 

[billslugg]

astroguard<br /><br />MeteorWayne asks for you to show the weaknesses in the mainstream view.<br />Yevaud points to:"consensus following many years, decades, of examination, observation, and tedious theorizing." <br /><br />After 11 days to study the mainstream view and come up with possible weaknesses you call the mainstream view "ad-hoc" (improvised, without preparation), and ask for more data.<br /><br />Not waiting 11 years, but given what we know now, can you cite some weaknesses in the mainstream view? <div class="Discussion_UserSignature"> <p> </p><p> </p> </div>