Where's the discussion on Stardust data?

[yevaud]

<i>The alternative is to propose that somehow our early sun threw material out to the vastest regions of the solar system, where the comet could somehow incorporate it--despite temperatures near absolute zero--into its composition, to be revealed to us four billion years later.<br /><br />Talk about ad hoc! </i><br /><br />I'll merely resply here, "T. Tauri Star." This isn't a guess and isn't a hypothesis. They are observed in every stage of their development, up to and including when the star evacuates a vast amount of material from around it, clearing it outwards. Note that last word: <i>outwards.</i><br /><br />As well, don't forget that Comets cycle in and out of the inner and outer systems during their evolution, and continue to accrete throughout. It's just as likely that that Olivine (and other substances) are remnants of the original Protoplanetary disc, or flung off of early planetary bodies. There's a wide range of possibles that do not require a hypothetical planet exploding. <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>

 

[dmjspace]

Yevaud said: <font color="yellow"> I'll merely resply here, "T. Tauri Star." This isn't a guess and isn't a hypothesis. They are observed in every stage of their development, up to and including when the star evacuates a vast amount of material from around it, clearing it outwards. Note that last word: outwards. </font><br /><br />That certainly wasn't the working hypothesis going into the Stardust mission. Scientists were surprised. Shocked. Stunned. They did not expect to have to propose the comet has been both hot and cold. Wild 2 is supposed to be as close to pristine as we can expect from a comet, given that it's estimated to have passed the sun a mere five times.<br /><br /><font color="yellow"> There's a wide range of possibles that do not require a hypothetical planet exploding. </font><br /><br />After the fact, there will certainly be many alternate possibilities considered, and the revisions are already being spun.<br /><br />However, the key is that the EPH explicitly predicted what has now been observed. The dirty snowball did not.<br /><br />The fair judgment of a theory's validity is whether it needs to be revised, particularly in fundamental ways, after observations are made. If so, the theory is weak. The dirty snowball model is clearly suffering at the hands of the evidence.

 

[TheShadow]

From the article: <i> Comets, they said, may not be as simple as the clouds of ice, dust and gases they were thought to comprise. </i><br /><br />Making such a broad statement from a sample of one is rather irresponsible. Depending on which data you use, nearly 1000 comets have been identified, and many times that are estimated to orbit through our solar system. If the Oort cloud exists, and if it is as theorized, there may be a trillion proto-comets out there. And they are going to determine the composition of all of them based on a sample of what %? Right.<br /><br />dmj says: <i> I can think of no better explanation for all of these factors than a former planet that resided in solar orbit for a significant amound of time. </i><br /><br />Perhaps that is because you haven’t considered other possibilities?<br /><br />dmj says: <i> Wild 2 appears to be a neat time capsule preserving the former planet's diverse composition, </i><br /><br />That doesn’t make an sense at all. If a planet did explode, and the fragments scattered through space, it is reasonable to assume that different fragments would be radically different in composition. Certain structures such as large rocky deposits would survive in relatively large chunks, probably consisting entirely of the same basic material. That would also be true of balls of molten magma. Other material, such as topsoil, mud, and sediment, would probably not form any type of surviving structure at all. It is far more likely that a chunk of an exploded planet would be a capsule of a single type of material.<br /><br />dmj says: <i> The alternative is to propose that somehow our early sun threw material out to the vastest regions of the solar system, </i><br /><br />Talk about ad hoc!!! Proposing a Strawman argument that is easy to knock down is one way to make your hypothesis <i>appear</i> to be more valid. There are many possible explanations of how this single comet ended up with the <i>surface composition</i> it now has. I th <div class="Discussion_UserSignature"> <p> </p><p> </p><p> </p><p> </p><p><font size="1" color="#808080">Who knows what evil lurks in the hearts of men, the Shadow knows. </font></p> </div>

 

[bonzelite]

underscore this:<br /><br /><font color="yellow"> We cannot even determine if this comet came from our solar system. </font><br /><br />remember that, all who are reading.

 

[jatslo]

Yep, the isotope ratio of the interstellar samples collected should tell us if, comets are extraterrestrial, or not. Meaning, not of this solar system, so, I guess, that would be extra-extraterrestrial. However, isotope ratios can be manufactured with existing technologies, so the methodologies should be as transparent as possible.<br /><br />Hopefully the samples are not too small to be tested; I heard rumors that they might be.

 

[jatslo]

A sample less than thirty only requires that we use the t-scale as opposed to the z-scale; therefore, the hypothesis stands until another sample says otherwise. The hypothesis that comets are "Dirty Snowballs" is *REJECTED*, but probability is not guaranteed by any means.<br /><br />I would also like to add that any hypothesis stating that Earth's oceans are a byproduct of comets is also *REJECTED*, which brings me to biological processes yet once again. As biology consumes matter it creates water, because water makes soluble what biology consumes. If that sounds circular, it is because it is.

 

[TheShadow]

jatslo says: <i> Yep, the isotope ratio of the interstellar samples collected should tell us if, comets are extraterrestrial, or not. </i><br /><br />What “interstellar samples” would those be? I wasn’t aware of any of our spacecraft that had attained the status of interstellar, and none at any significant distance from our Sun capable of comprehensive analysis of samples. Even Voyager I and II have not passed the Heliopause, so they are not in a position to intercept raw interstellar samples.<br /><br />Even if we do someday obtain those interstellar samples, they wouldn’t tell us whether comets come from our solar system or another one. Incidental interstellar particles would be a very small percentage of the makeup of a comet that came from another solar system.<br /> <div class="Discussion_UserSignature"> <p> </p><p> </p><p> </p><p> </p><p><font size="1" color="#808080">Who knows what evil lurks in the hearts of men, the Shadow knows. </font></p> </div>

 

[jatslo]

Stardust took two samples; one of star dust, or nebula dust, and comet dust, and the isotope ratio's will tell us if the comet originated within our solar system. Comparing the two samples will just reaffirm the outside source, is all. Anything outside of our solar system will have exotic isotope readings, and that is why isotopes are so important in extraterrestrial research. However, existing technology can fabricate artificial isotope readings, so transparency in methodologies is required.<br /><br />The interstellar samples have exotic isotope readings not of our solar system when compared, and/or manufactured materials have exotic isotope signatures when fabricated, period.<br /><br />Stardust actually brought samples back for analysis along with the comet dust, or did I say that already?

 

[dmjspace]

TheShadow said: <font color="yellow"> Making such a broad statement from a sample of one is rather irresponsible. </font><br /><br />There should be no statement made that doesn't fit the observational evidence. The statement (and assumption, for a long time) that comets are substantially different from asteroids is unwarranted, given that known densities and compositions cannot distinguish the two.<br /><br />So far, the EPH's predictions have been fulfilled. The dirty snowball's predictions have not, hence the constant revisions of the snowball model.<br /><br />What you appear to be arguing is that, yes, the data we have now do NOT support the snowball model, BUT that more observations should confirm it in the future.<br /><br />Well, scientists have been saying that for a long time. So far it hasn't panned out. There is a point at which a model's underlying assumptions should be questioned. Now is the time to revisit the "Oort cloud" (which even Oort himself considered a remote possibility) aspect of the model.<br /><br /><font color="yellow"> If the Oort cloud exists, and if it is as theorized, there may be a trillion proto-comets out there. And they are going to determine the composition of all of them based on a sample of what %? Right. </font><br /><br />Scientists have long "determined" the composition of comets based on ZERO samples. Now they have ONE sample, and it contradicts the model in fundamental ways. <br /><br />How many samples would you like to see that contradict the model before reexamining the underlying assumptions?<br /><br /><font color="yellow"> That doesn’t make an sense at all. If a planet did explode, and the fragments scattered through space, it is reasonable to assume that different fragments would be radically different in composition. </font><br /><br />Yes. There are many types of asteroids. The EPH merely suggests that comets are rocky bodies, like asteroids. We see the variation the EPH predicts. It is the dirty sn

 

[vogon13]

EP<font color="yellow">H</font>is rapidly being supplanted by the planet dissolving chaos cloud <i><b><font color="yellow">fact</font></b></i><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>

 

[TheShadow]

dmj says: <i> The statement (and assumption, for a long time) that comets are substantially different from asteroids is unwarranted, </i><br /><br />Let me get this straight. Comets outgas enormous amounts of volatiles and dust. Asteroids do not. They are not substantially different. Gotcha.<br /><br />dmj says: <i> What you appear to be arguing is that, yes, the data we have now do NOT support the snowball model, BUT that more observations should confirm it in the future. </i><br /><br />Not at all. I am saying that the data neither confirms nor refutes the snowball model because it is not nearly complete or comprehensive enough.<br /><br />dmj says: <i> Yes. There are many types of asteroids. yadda….yadda….yadda……..</i><br /><br />Nice non sequitur. I pointed out that your comment about this sample representing “the former planet’s diverse composition” did not make sense, and you come back with …….???<br /><br />dmj says: <i> But the EPH has 100 lines of evidence supporting it </i><br /><br />So you claim. Meanwhile, there is not enough material in the asteroid belt to make even a very small moon, let alone a planet. The claim of vaporization appears to be solely an ad hoc and woefully inadequate patch on a gaping hole in the EPH.<br /><br />dmj says: <i> By the way, if you read NOTHING else in my post above, and wouldn't believe a word of it even if you did, at least check out the section "Satellites of Asteroids and Comets" </i><br /><br />I don’t see the significance. Any body of sufficient size should be able to capture satellites under the right conditions. Claims that accretion-formed bodies would “invariably be isolated bodies” appears to be just as ad hoc and unsupported as the “vaporization” claim. If you are anchoring your beliefs to that claim, I suggest you invest in a good safety line.<br /><br />dmj says: <i> Asteroids and comets should absolutely NOT have satellites, nor evidence of past satellites </i><br /><br />Given the time frame involved, and the amount <div class="Discussion_UserSignature"> <p> </p><p> </p><p> </p><p> </p><p><font size="1" color="#808080">Who knows what evil lurks in the hearts of men, the Shadow knows. </font></p> </div>

 

[yevaud]

Determining the extrasolar origin of a Comet: isotope ratios, which will be somewhat different if said Comet originated in a different solar system. That being said...<br /><br />Bonzelite: <i>underscore this:</i><br /><br />Shadow: <i>We cannot even determine if this comet came from our solar system.</i><br /><br />Bonzelite: <i>remember that, all who are reading.</i><br /><br />Comportment, please. Don't go pointing the finger, lest others do it to you.<br /><br />(Edited for simplicity and clarity, and since Jatslo seems to feel the original comment was "objectionable" to him) <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>

 

[jatslo]

Yep, Isotopes are the trick ...<br /><br />[edited, because Yevaud edited out - TY]

 

[dmjspace]

TheShadow said: <font color="yellow"> Let me get this straight. Comets outgas enormous amounts of volatiles and dust. Asteroids do not. They are not substantially different. Gotcha. </font><br /><br />Their *nuclei* are not substantially different. Take a look at this comparison between a comet nucleus and an asteroid nucleus. They are virtually indistinguishable. All of our observations of comet nuclei show them to be extremely similar to asteroids in terms of albedo and surface features.<br /><br />But of course you are correct in that comets, having spent most of their time far from the sun, have not yet had their volatiles baked out of them like asteroids have. As Van Flandern explains, "In the EPH, comets are young, solid, rocky bodies surrounded by gravitationally bound dust and debris fragments of all sizes from the original explosion. The water ice present is mostly interstitial."<br /><br />The key is that comet nuclei are composed of rock, and the coma is composed mostly of dust. These concepts are central to the EPH, but directly contradictory to the competing "dirty snowball" model, which holds that comets are pristine, mostly icy remnants. <br /><br /><font color="yellow"> Nice non sequitur. I pointed out that your comment about this sample representing “the former planet’s diverse composition” did not make sense, and you come back with …….??? </font><br /><br />You suggested that, in the EPH, there should be different types of bodies from different planetary layers. I acknowledged that, yes, there should be. And there are. <br /><br />But unlike the dirty snowball model, the EPH suggests that carbonates and silicates should dominate, not ice. Observations strongly support the EPH in this aspect.<br /><br /><font color="yellow"> The claim of vaporization appears to be solely an ad hoc and woefully inadequate patch on a gaping hole in the E</font>

 

[CalliArcale]

<blockquote><font class="small">In reply to:</font><hr /><p>What “interstellar samples” would those be? I wasn’t aware of any of our spacecraft that had attained the status of interstellar, and none at any significant distance from our Sun capable of comprehensive analysis of samples. Even Voyager I and II have not passed the Heliopause, so they are not in a position to intercept raw interstellar samples. <p><hr /></p></p></blockquote><br /><br />Actually, Stardust collected interstellar dust samples. They're on the flip side of the same collection grid as the Wild-2 samples.<br /><br />Interstellar dust is not completely deflected by the heliosphere, any more than the Earth is completely shielded from solar particles by its magnetosphere. There is a stream of dust particles that come from outside of our solar system. Stardust attempted to capture some during two collection periods, taking advantage of the long cruise to Wild-2. I have not heard anything about them, probably because the comet dust is taking precedence. <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>

 

[CalliArcale]

The Royal Astronomical Society is releasing results of their study of Tempel 1 using Swift during the Deep Impact collision. They report an increase in X-ray light from the comet lasting for twelve days, directly measuring the amount of water released. The total mass of water liberated by the impact was 250,000 tonnes. Interestingly, this is in contrast to visible light observations, which showed an increase in brightness for only five days. This suggests that the impact did not cause a huge outburst (a possible blow to the theory that micrometeroid impacts provoke cometary outbursts) but instead caused a much slower outgassing.<br /><br />http://www.spaceflightnow.com/news/n0604/04deepimpact/ <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>

 

[dmjspace]

CalliArcale said: <font color="yellow"> The Royal Astronomical Society is releasing results of their study of Tempel 1 using Swift during the Deep Impact collision. They report an increase in X-ray light from the comet lasting for twelve days, directly measuring the amount of water released. The total mass of water liberated by the impact was 250,000 tonnes. </font><br /><br />I suspect that the implications of this study will be debated intensely. The team's assumptions about water being the cause of X-rays may be challenged, even by dirty snowball proponents.<br /><br />The two things that strike me about it are:<br /><br />1) Tempel 1 was producing 16,000 tons of water a day already.<br /><br />The report directly contradicts the finding of the report from Harvard-Smithsonian Center for Astrophysics, which suggests no post-impact water vapor increase occurred. It will be interesting to see what this team's response is to the Swift data.<br /><br />2) Because dirty snowball proponents rarely make specific predictions to test the model, it is difficult to tell whether the alleged increase is related to the subsurface material, or if it was simply the result of liberation of icy dust particles from the comet's extensive regolith.<br /><br />As the RAS admits: "Most of the water seen in X-rays came out slowly, possibly in the form of ice-covered dust grains."<br /><br />Despite the splashy headline of the article, it is clear that Tempel 1 is far more dust than ice.

 

[robnissen]

I was wondering if you would pipe in on this subject, DMJSPACE. Even though I think the EPH hypothesis (it lacks sufficient evidence to be a theory) is flat wrong, I think you do raise some interesting arguments regarding potential flaws in the dirty-snowball / snowy-dirtball comet theory. Also, unlike some of your fellow travelers, you will at least recognize contradictory data, even if you then immediately explain it away. This is a long-winded way of saying I enjoy reading your posts.

 

[dmjspace]

RobNissen said: <font color="yellow"> I was wondering if you would pipe in on this subject, DMJSPACE. </font><br /><br />Yes, I like to "pipe in" on a subject occasionally. And when I do, I like to include some specific data to support my position. You should try it sometime. <img src="/images/icons/smile.gif" /><br /><br /><font color="yellow"> Even though I think the EPH hypothesis (it lacks sufficient evidence to be a theory) is flat wrong, </font><br /><br />Have you read Van Flandern's "Dark Matter" book? It lays out 100 lines of evidence that illustrate the differences in the predictions between the EPH and the dirty snowball model. The EPH is overwhelmingly supported by observation, while the dirty snowball model falters in fundamental ways.<br /><br />It's a good book. I recommend it to anyone serious about figuring out the answer to the comet/asteroid question.<br /><br /><font color="yellow"> Also, unlike some of your fellow travelers, you will at least recognize contradictory data, even if you then immediately explain it away. </font><br /><br />I didn't necessarily explain it away. I did point out that even the snowball proponents' data contradict each other, however.<br /><br /><font color="yellow"> This is a long-winded way of saying I enjoy reading your posts. </font><br /><br />Seeing as how I don't get too many compliments from the other side of the aisle, I will definitely take this one and run with it. Thanks.