Talk:Nebular hypothesis/Archive 1

Archive 1

Speculators

People who proposed the nebular hypothesis were Tycho Bobostein, Johannes Kepler, Edmond Halley, Emanuel Swedenborg, Immanuel Kant, Johann Heinrich Lambert, Rudjer Boscovich, Pierre-Simon Laplace, William Herschel, and Maria Mitchell.Lestrade 14:13, 8 March 2006 (UTC)Lestrade

The hypothesis has been confirmed.[1]69.6.162.160 01:03, 10 October 2006 (UTC)Brian Pearson

Where did the solar nebula come from?

Where did the solar nebula come from? I'd like to know. It must have come from a supernova from earlier in the history of the universe (to account for the heavy elements on earth.) Can anyone write anything about this? I think it's significant. Jolb 02:04, 29 October 2006 (UTC)

Merge with Formation and evolution of the solar system?

These two articles have a lot of overlap, and there is information in this article that really needs to be in the other. Some kind of mergence would tidy things up a lot. Serendipodous 18:46, 20 November 2006 (UTC)

I've been thinking about this for a while, and I agree. There's a lot of material in here that's only applicable to our Solar System, which Formation and evolution of the solar system can do a much better job with.

It's a grand undertaking, but I'd like to see the material relevant to our system the merged with the other article, and this article to become a general discussion of planetary system formation, from cloud collapse to final orbits. Really, that's already what it is, but it's tailored to our particular corner of the universe, and there's already an article for that. There are so many known exoplanets now that this sort of article needs to speak in broader terms. This could be renamed Theory of planet formation, or Formation of planetary systems, or some such, and leave the other article to specialise on our system, which we know much more about.

There are also a lot of disparate planetary articles - accretion disc, planetesimal, protoplanet, planetary migration, planetary differentiation, accretion (astrophysics), etc. - and tidying up this one into a quick guide through the whole process could be a good way of connecting them all up and providing some structure, just as universe does for the evolution of our universe. Needless to say, I'd be happy to help. I guess that's kinda why I signed up. Spiral Wave 14:52, 23 November 2006 (UTC)

Summary for anyone wondering why chunks are being removed from this article: Overlap between this and Formation and evolution of the solar system is quite bad, though it's more conceptual than actual content, Heavy Bombardment excepted. I intend to turn this into a general article on planet formation (something that already links here), and move the Solar System-specific content to the other article. There's a larger discussion on the matter over at that article's talk page. Spiral Wave 15:48, 21 January 2007 (UTC)

Made a bit more generic, eg turning each reference of 'Sun' into 'star'. There's still a few more sections to be added for this to be a true 'planet formation' discussion, eg planetary migration, turbulence, a bit more on dust settling, gravitational instability. And lots of references, of course. But it's getting there. Spiral Wave 06:53, 22 January 2007 (UTC)

"Among the observed extrasolar planetary systems, the distribution of the planets in our own system may as yet be considered somewhat"

Somewhat what? Serendipodous 09:23, 22 January 2007 (UTC)

Oops. Please don't shout so loudly; it's a bit too early. Spiral Wave 10:08, 22 January 2007 (UTC)

Sorry; I am a bit hard of hearing. Serendipodous 10:27, 22 January 2007 (UTC)

Renaming of article to Planet formation?

As explained above, I've been working on sorting out the duplicate material between this article and Formation and evolution of the solar system. It was already hovering inbetween being specific to our Solar system, and a general discussion, so I'm working on generalising it further so we have a full article leading through the process of planet formation. I feel this article now needs renaming to reflect this change. Planet formation already links here; formation of planetary systems has also been suggested. If anyone has any opinions, or knows how to do all the necessary moving while preserving histories and (double?) redirects and so on, please speak up. I'm also left wondering if Solar Nebula should now be a redirect somewhere else; perhaps to Formation and evolution of the solar system. It's outgrown the original title and I've already moved most of the relevant content to the appropriate section there. Spiral Wave 14:29, 22 January 2007 (UTC)

Just noticed - planet formation links here, but planetary formation links to protoplanetary disk. That needs tidying up too. Spiral Wave 14:32, 22 January 2007 (UTC)

I'm not sure yet; this whole series of articles is in a bit of a mess; I just got back from "Sun" and found nothing about formation in it at all. Merging "Protoplanetary disc" wouldn't be so difficult, as it isn't very large. Serendipodous 14:35, 22 January 2007 (UTC)

it's definitely a mess. The structure I'm aiming for is one 'central' article, on planet formation, each with a short piece describing and linking to the relevant larger article - protoplanetary disc, protostar, planetesimal etc. Kind of like how universe is attempting. So I'd rather keep protoplanetary disc separate; if we brought in everything like that, for each subsection, we'd get one huge article, which probably isn't too helpful. But I'm open to any better suggestions. Spiral Wave 16:19, 22 January 2007 (UTC)

(Uh, that means better than mine, not better than what you just said, BTW, That could be taken the wrong way. ) Spiral Wave 22:34, 23 January 2007 (UTC)

Move request

The following discussion is an archived discussion of the proposal. Please do not modify it. Subsequent comments should be made in a new section on the talk page. No further edits should be made to this section.

• Solar nebula → Nebular hypothesis —(Discuss)— This title of this article is simply wrong. The "solar nebula" is not the nebula out of which the Sun and solar system formed. That nebula is called the "presolar nebula." The solar nebula is the residue remaining after the formation of the Sun that went on to form the planets. I can provide a number of scholarly references (here, here, here, here, here, here, and here) which describe the mass of the solar nebula as far less than that of the Sun, which would be impossible if the Sun formed out of the solar nebula. Regardless, this article goes far beyond describing the solar or presolar nebulae. It is in fact an account of the nebular hypothesis of the formation of the solar system, and should be described as such. Serendipodous 06:43, 29 July 2007 (UTC)

Discussion

• Object — Then the article needs to be clarified. But discussion of the formation of the Sun seems necessary as a precursor to discussion of the "solar nebula". "Solar nebula" gets many more ghits, so I take it to be the more common term. I also get 7633 matches on NASA ADS for "solar nebula" compared to 1027 for "nebular hypothesis". The former seems the more scientific term, whereas the later is more historical. — RJH (talk) 15:39, 1 August 2007 (UTC)

Relying on Google hits is misleading in this case because "solar nebula" is an accepted term in planetary science. But not for the primordial nebula out of which the Solar System formed. In planetary science, the solar nebula is the remainder left over after the formation of the Sun that went on to form the planets. Thus this article's lead is incorrect. The solar nebula only existed for a fraction of the time described in this article, and indeed, by the time described in "Giant impacts" was already gone. It seems strange then, that it is the article's title. Serendi^podous 16:00, 1 August 2007 (UTC)

• Support - The article as it stands now appears to be primarily about the hypothesis. While not getting into the details of what is or is not meant by "the solar nebula", I would expect this article to be titled to indicate that it describes a hypothesis, not a physical object. Perhaps a secondary article on the physical object itself would be better suited to the title of "Solar nebula". -dmmaus 04:54, 3 August 2007 (UTC)

The above discussion is preserved as an archive of the proposal. Please do not modify it. Subsequent comments should be made in a new section on this talk page. No further edits should be made to this section.

This article has been renamed from solar nebula to nebular hypothesis as the result of a move request. --Stemonitis 07:26, 3 August 2007 (UTC)

"Solar nebula" vs. "pre-solar nebula"

I've been confused for a while by Wiki's usages of the term "solar nebula". From what I've been able to gather reading astronomical articles, the term "solar nebula" applies not to the original cloud but to the "residue" left over after the formation of the initial protostar that ultimately led to the formation of the planets. The initial nebular cloud pocket is called the "pre-solar nebula", while the great stellar nursery of which the solar nebula was a part is called the "giant molecular cloud". See this powerpoint presentation:

[2]

I think this article needs to be renamed "Pre-solar nebula" Serendipodous 11:14, 19 February 2007 (UTC)

The whole thing's a mess. I don't know what this was originally intended to be, but it's become an explanation of the process of planet formation - disc, planetesimals, jovian cores, giant impacts. Which is possibly why the nomenclature is highly inconsistent between articles. I intend to fill in the gaps and complete that explanation (but I've ended up doing other things for the time being). In my mind, this should then be re-named planet formation (as explained above); pre-solar nebula could become the 1st stage of this article (with a link to molecular cloud as the main article), or a separate one. Once I have added a lot to this article, I will push hard for the move. Spiral Wave 11:34, 19 February 2007 (UTC)

As a compromise, I'd be willing to accept this article become purely about the solar nebula, as a kind of special case of protoplanetary disc, since we know more about our own local conditions. But that would involve the creation of a new planet formation article, and most of sections 1.2 - 1.8 from here would be moved (or at least copied) over there. Spiral Wave 12:06, 19 February 2007 (UTC)

As a start to the cleanup, I've shifted the material in this article to planetary formation, created a link to planetary formation at protoplanetary disk, and created a stub article on the solar and presolar nebulae. It's not much but it's a start. Serendipodous 15:46, 19 February 2007 (UTC)

Yeah, I suppose it's better to get stuck in now than decide to move more concrete articles at a later date, after they've been heavily added to. I think this will simplify things in the long run. Spiral Wave 15:49, 19 February 2007 (UTC)

Discussion post move to "Nebular hypothesis"

The large article that used to be at this location has been moved for good or ill to "nebular hypothesis". The "Solar nebula" is a term referring to the nebula from which the Sun and the solar system both formed. The process by which this is thought to have happened is described in the nebular hypothesis article. This article, therefore, does not need expanding. It should not be a stub. It needs a short description, and a big fat link pointing to the nebular hypothesis article. Myrrhlin 21:53, 16 April 2007 (UTC)

The term "solar nebula" is generally applied to the "leftovers" after the formation of the Sun that formed the planets. The nebula out of which the Sun formed is called the "presolar nebula." Serendipodous 21:57, 16 April 2007 (UTC)

That is not correct, in my understanding. The references at the bottom of this page are not trustworthy, and in some respects demonstrably inaccurate. The textbooks I use are fairly consistent on this point of terminology. I would not be surprised, however, if you can find another convention. But I think Kant et al. who proposed the original nebular hypothesis were talking about the formation of the entire solar system, not just the planets. It does not make sense to talk about a collapsing, flattening, heating, spinning cloud, that will become the planets separate from the sun. They come from the same cloud. The disk where the planets form is called a protoplanetary disk. The "solar nebula" is not simply a protoplanetary disk. The solar nebula came BEFORE the protoplanetary disk.

Where did you learn that "solar nebula" does not include the proto-sun? Myrrhlin 22:21, 16 April 2007 (UTC)

Here, here, here, here, here, here, and here all give an estimate for the mass of the solar nebula as 0.1 the mass of the Sun. This would be ludicrous if the solar nebula also included the Sun. Serendipodous 07:06, 17 April 2007 (UTC)

As those references show, Serendipodous is correct, "solar nebula" refers to the nebula (really a disc) around the Sun, not the nebula from which it formed (which is the "presolar nebula"). The relevant paragraph needs correcting appropriately, but I don't want to start an edit war so I'll wait for any objections here before changing anything. Meanwhile, if anyone can come up with any evidence showing that solar nebula does actually (commonly) mean the precursor cloud, then that alone is reason to give them a separate article to planet formation/nebular hypothesis: so that the two different meanings can be explained and clarified, away from the nebular hypothesis argument. Mixing them all up together is a recipe for confusion. Spiral Wave 19:38, 22 April 2007 (UTC)

NOTE: an admin then moved the article back from nebular hypothesis to solar nebula without allowing further discussion on the matter. Serendipodous 06:47, 29 July 2007 (UTC)

Links?

What the heck is with that ALL CAPS link? It doesn't point to anything valid. I'm deleting it, but here's the original:

INJECTION OF RADIOACTIVE NUCLIDES FROM THE STELLAR SOURCE THAT TRIGGERED THE COLLAPSE OF THE PRESOLAR CLOUD CORE

--130.157.41.169 19:50, 7 March 2007 (UTC)

Link fixed. It mainly describes the theory that the presolar nebula began its collapse after being disturbed by a supernova. Serendipodous 20:59, 7 March 2007 (UTC)

Links

PS I would argue for removal of at least two of those external links. The summary for 9th-graders with group activity is quite inaccurate. In the PPT presentation linked, the author claims the collapse of the solar nebula was triggered by a supernova. While that is a possibility, its pure speculation. I've not seen any research to support this. Could just as likely (perhaps more so) have been a passing spiral density wave, or no particular cause. Myrrhlin 22:27, 16 April 2007 (UTC)

Fine by me. It's not like there are that many sources anyway. If you feel that they could be improved, go for it.Serendipodous 07:19, 17 April 2007 (UTC)

Planetary Formation

I noticed that the topic of 'Planetary formation' is linked to here. MegaHasher 00:19, 29 July 2007 (UTC)

Yeah. That's an issue. The fact is, and this is a point I've made dozens of times, the solar nebula is NOT the original cloud out of which the Solar System formed. That's called the pre-solar nebula. The Solar nebula is the residue left over after the Sun formed that ultimately formed the planets. Even though I provided eight scholarly references to that effect, people still refused to move the topic, and since the topic has already been moved, I can't do it without admin approval. Serendipodous 06:08, 29 July 2007 (UTC)

I also see other references with different usages, such as [3] and [4]. I don't have textbooks handy for additional checks. MegaHasher 01:11, 30 July 2007 (UTC)

solar features consistent with the nebular-hypothesis

the planets are all in the ecliptic (except for pluto), they all have right-hand revolution around sun, they all have right-hand rotation, including sun, excepting Uranus and Earth (the 90 and 23 degree offset is believed to be due to impacts (moon in earth's case)

Do the planets' moons also have mostly right-hand rotations & revolutions on the ecliptic ? These would mostly be captured planitesimals out of the accretion disk, perhaps with the random & rare capture of an object which was previously dislodged out of its circular ecliptic orbit, and then possibly impacting, or being captured in an off-ecliptic orbit, by another planet ?

Does the Milky-way also have a right-hand rotation ? Is it a possible source of the angular momentum in a pre-solar nebula ? Do most stars also have a right-hand rotation (if this is observable) ?

Swedenborg

The Swedenborg claim is referenced only to an original work of Swedenborg. I have no access to it and there is an obvious worry that this is an unpublished synthesis. There is no mention of Swedenborg in the (2001) Encyclopaedia Britannica article on "Solar system:Origin of the solar system" though it mentions Kant and Laplace, going so far as to talk about the "Kant-Laplace nebular hypothesis". Can we have a citation to some secondary interpretation please? Cutler 23:18, 24 August 2007 (UTC)

[5] Go here if you want more references. Look at section D and the following.

Jasonschnarr 18:04, 25 October 2007 (UTC)

Rewrite of the article

I prepared this text, which I want to insert into the article. Talk:Uranus/new_subpage. Ruslik 11:26, 24 October 2007 (UTC)

Template:Star formation

I would like to suggest adding this template to help interlink all of the articles based on star formation. I would do it myself but I don't know how to without upsetting the formatting of the article.Coffeeassured (talk) 00:23, 13 April 2008 (UTC)

I will probably add it soon. Ruslik (talk) 08:16, 13 April 2008 (UTC)

Coagulation - eggs?

Coagulation, isn't that when proteins change form by heat or by chemical processes to form some kind of soft but solid matter, common for frying or cooking eggs and other food processing? Funny that the planets were formed in this way. Said: Rursus (☻) 13:50, 29 December 2008 (UTC)

Coagulation has several meanings. Ruslik (talk) 14:50, 29 December 2008 (UTC)

Well, then Wiktionary needs updating, since it doesn't even mentions eggs, but only blood and tofu. And Wikipedia concentrates on eggs, blood and proteins. I instead propose "accretion", which is more like a conventional term regarding planet creation. Although coagulation is an attractive term, when I'm hungry, and might consider fried eggs. Said: Rursus (☻) 17:44, 29 December 2008 (UTC)

Coagulation is used in the literature fairly frequently. See [6] and [7]. Coagulation is just a process when particles stick to each other forming larger particles. This works for proteins as well. Ruslik (talk) 19:39, 29 December 2008 (UTC)

OK, noted and accepted. Thank you for the links. The articles on coagulation in Wiktionary and in Wikipedia maybe needs some enhancement though. Said: Rursus (☻) 08:22, 30 December 2008 (UTC)

See Coagulation (disambiguation). Ruslik (talk) 11:00, 30 December 2008 (UTC)

Needs some editing

The article could use some editing for style and minor typographical errors. Schaffman (talk) 14:13, 31 January 2009 (UTC)

A new source 2B used

Just dropping this link on accretion using magnetism to explain why larger than cm-sized objects may form:

uu.diva-portal.org/smash/record.jsf?pid=diva2:173154 Lyra, Wladimir "Turbulence-Assisted Planetary Growth: Hydrodynamical Simulations of Accretion Disks and Planet Formation"

The cursed spam-filter is prohibiting me for adding this serious link! (Now, I'm pissed!) ... said: Rursus (bork²) 11:06, 26 February 2009 (UTC)

That was probably a temporary glitch:

Lyra, Wladimir "Turbulence-Assisted Planetary Growth: Hydrodynamical Simulations of Accretion Disks and Planet Formation"

... said: Rursus (bork²) 11:31, 26 February 2009 (UTC)

Swedenborg

I think Swedenborg's theory should be downplayed: it is not enough if a person claims it first, the person should have good arguments to propose it, and there should also be some remembrance, continuity and acceptance of the claim via later scientists to the current state of science. Wegener is regarded the original proposer of continental drift, not because he was first, but because he was the first to provide arguments based on fossils and geology, not just saying that the Americas and the Africas split apart based on the similarity of their coast lines. Rursus dixit. (^mbork³!) 17:23, 26 December 2011 (UTC)