Wikipedia:Featured article candidates/Magnetosphere of Jupiter/archive1

The following is an archived discussion of a featured article nomination. Please do not modify it. Subsequent comments should be made on the article's talk page or in Wikipedia talk:Featured article candidates. No further edits should be made to this page.

The article was promoted by SandyGeorgia 21:30, 16 June 2009 [1].

---

Magnetosphere of Jupiter

Nominator(s): Ruslik, Serendipodous.

• Featured article candidates/Magnetosphere of Jupiter/archive1

I am nominating this for featured article because it is a vital article for the Solar System WikiProject. It was which written in the past several month essentially from the scratch and passed a peer review. I should warn that the article is complected and requires an effort to understand. I tried to make it as simple as possible, however, magnetospherics is a complicated subject, which is difficult to write about. I still hope that the complexity of the article will not be dissuaded reviewers from reviewing it. Ruslik_Zero 18:51, 3 June 2009 (UTC)

This is co-nomination with Serendipodous. Ruslik_Zero 13:10, 8 June 2009 (UTC)

Thank you. :-) Serendi^podous 15:54, 8 June 2009 (UTC)

• Comments: The complexity of the article does not dissuade me from reviewing it, but from what I've seen so far, it will likely dissuade readers from reading it. In order to help remedy this, I have initiated a line-by-line review which, per this suggestion by SandyGeorgia, is being listed at the article's talk page. --Cryptic C62 · Talk 22:45, 3 June 2009 (UTC)

  Fixed everything except that magnetic field and magnetosphere are not the same thing. Ruslik_Zero 10:51, 4 June 2009 (UTC)

  Would you mind responding to the concerns individually on the talk page? It would make more sense to keep any discussion which might arise (such as magnetosphere vs. magnetic field) connected to the relevant concern rather than cluttering up this page. --Cryptic C62 · Talk 04:00, 5 June 2009 (UTC)

• I'll leave sporadic comments here as I go through the article, as I can't review it in one sitting. But so far, in the lede, several possessives disrupt the flow of the article when read out loud (minor issue). In the discovery section, you have to make sure you don't leave the audience behind. I'm sort of knowledgeable in this stuff, but I got lost in the DAM until I realized you were talking about the wavelengths of the particular electromagnetic emission. You may want to link to wavelength there somehow. Titoxd^{(?!? - cool stuff)} 07:46, 4 June 2009 (UTC)

  Fixed. Ruslik_Zero 10:51, 4 June 2009 (UTC)

• It is located at the distance from 45 to 100 Rj (where Rj=71,492 km is the radius of Jupiter) from the planet at the subsolar point; the unfixed point at which the Sun appears directly overhead.[6] - an emdash might be better instead of the semicolon, but that's not my main complaint. The wording about the positioning of the subsolar point is not clear; do you mean that the subsolar point moves? If it does, depending on what? Variations of the solar wind, orbital elements of Jupiter, rotation of the planet, or other factors? Also, "at the distance" sounds awkward, for some reason. Titoxd^{(?!? - cool stuff)} 08:08, 4 June 2009 (UTC)

  Fixed. Ruslik_Zero 10:51, 4 June 2009 (UTC)

• Tend to Support - the quality has improved a lot. The article is well written. That said, the review process is not finished yet. Materialscientist (talk) 00:21, 7 June 2009 (UTC)
  • Jupiter.Aurora.HST.mod.jpg is by the nominator and is unreadable. I strongly recommend increasing letters there. If not possible, the image should be stretched (nearly) full width. A bit of cropping is also advised.

    I increased font size. Ruslik_Zero 13:22, 4 June 2009 (UTC)

    Sorry, symbols could and should be larger and readable even in a thumb image (there is plenty of space in that figure). This is not nitpicking.Materialscientist (talk) 00:33, 5 June 2009 (UTC)

    Increased further. Ruslik_Zero 09:43, 5 June 2009 (UTC)

  • Radio emissions of Solar System planets.png - Abbreviations should be explained in the figure caption.

    This will make the caption very long. Ruslik_Zero 13:22, 4 June 2009 (UTC)

    The unspoken rule is delete unexplained abbreviations or explain them in the caption; or both. KOM,HOM,DAM are defined in the text. I was referring to SKR,AKR,TKR,UKR,NKR. The caption there can still be expanded 2-4 fold. Materialscientist (talk) 00:33, 5 June 2009 (UTC)

    I added explanation. Ruslik_Zero 09:43, 5 June 2009 (UTC)

  • PIA04433 Jupiter Torus Diagram.jpg needs cropping.

    Cropped. Ruslik_Zero 09:43, 5 June 2009 (UTC)

  • "Jupiter's field also has quadrupole, octupole and higher components, though they are weaker by an order of magnitude" - weaker than what ? Off course multipoles are weaker than the dipole; and if you compare with Earth, its dipole is weaker 10 times too. Materialscientist (talk) 11:47, 4 June 2009 (UTC)

    Why Of course? The higher moments may be comparable with dipole. Ruslik_Zero 13:22, 4 June 2009 (UTC)

    I am happy to admit my wrongs, but please enlighten me on the following: multipoles originate from series expansion of magnetic energy by a small parameter (general procedure in physics when the function is unknown). For the process to be justifiable, the series must rapidly decrease with the order (of the multipole). When the multipoles are comparable to the dipole, the series will not converge, and the whole expansion procedure is incorrect. Materialscientist (talk) 00:33, 5 June 2009 (UTC)

    I have never said that all harmonics are comparable to the dipole. Of course, beginning with some n they start to decrease. I only meant that the dipole is not necessary the strongest component. For example, the Sun's magnetic field is generally non-dipolar. Ruslik_Zero 09:43, 5 June 2009 (UTC)

  • "This makes Jupiter's magnetic field 10 times stronger than Earth's, and its magnetic moment 18,000 times larger" - I guess this hinges on the difference in the radii, which should be mentioned if so. Materialscientist (talk) 11:47, 4 June 2009 (UTC)

    Could you clarify this comment? Ruslik_Zero 09:43, 5 June 2009 (UTC)

    Magnetic moment is a product of the equatorial surface field and the cube of the planetary radius; that is why 18,000. We know that, but the reader might not even know the ratio of radii Jupiter/Earth. This all needs to be included, in some, perhaps simplified form. Materialscientist (talk) 10:33, 5 June 2009 (UTC)

    Fixed. Ruslik_Zero 08:54, 6 June 2009 (UTC)

  • "and is remarkably stable; no changes in its strength or structure have been observed since the first measurements were taken by the Pioneer spacecraft in the mid-1970s" - weasel. Please specify the stability. Materialscientist (talk) 11:47, 4 June 2009 (UTC)

    I added a stability estimate. Ruslik_Zero 09:43, 5 June 2009 (UTC)

  • "it would appear five times larger than the full moon in the sky despite its far greater distance" - Weasel again. Please mention number for the distance ratio. Materialscientist (talk) 11:47, 4 June 2009 (UTC)

    Mentioned. Ruslik_Zero 09:43, 5 June 2009 (UTC)

  • You heavily use "current" without explaining its particles: electrons ? ions ? If ions, which ones ?

    This is not really important. The current is defined simply as curl of B. Ruslik_Zero 13:22, 4 June 2009 (UTC)

    Disagree. Why it is important: you mentioned in the article electrons, oxygen and sulfur ions, and the reader will extrapolate that those cause the Jupiter currents. You must address what constitutes the current. If it is unknown yet, please describe it that way. Materialscientist (talk) 00:33, 5 June 2009 (UTC)

    This question is not so simple and can not be answered unequivocally. For one thing, the division into the ion and electron components depends on the choice of the frame of reference. For instance, in the frame where the plasma as a whole is at rest, all currents are electronic. Another example: the plasma in the magnetosphere co-rotates with the planet (with velocity of 300 km/s in the case of Jupiter), and the ring current flows in the direction of the co-rotations. What does this actually mean? It means that ions move slightly (by 0.2 km/s) faster than electrons. A question arises: if this current is ionic (because ions move slightly faster than electrons) or electronic (because electrons move slower)? If I make any these two statements I will likely mislead readers. Ruslik_Zero 09:43, 5 June 2009 (UTC)

  • "It consists of two lobes, with the magnetic field in the northern lobe pointing away from Jupiter and the southern pointing towards it. The lobes are separated by a thin layer of plasma called the tail current sheet." - strongly recommended to add a picture on that (even Earth's one is better than nothing) - it relies too much on imagination. Materialscientist (talk) 11:47, 4 June 2009 (UTC)

    I added an image. Ruslik_Zero 13:43, 4 June 2009 (UTC)

  • "The electrical conductivity of the plasma within the torus is not infinite, and as a result the plasma slowly leaks away from Jupiter." - very unconvincing causality. I suggest accurate reformulation of the reason for plasma loss, or, if too many reasons, avoid causality at all. Materialscientist (talk) 11:47, 4 June 2009 (UTC)

    I reworded this part. Ruslik_Zero 13:22, 4 June 2009 (UTC)

  • When discussing the field shape, you use "disk" and "flattened pancake-like structure". If there is no difference between those, please unify, if there is, please explain. Materialscientist (talk) 11:47, 4 June 2009 (UTC)

    Clarified. Ruslik_Zero 09:43, 5 June 2009 (UTC)

  • The sentence "A current flows from the ionosphere along the magnetic field lines to the equatorial ..." is much too heavy and should be split up.Materialscientist (talk) 11:47, 4 June 2009 (UTC)

    I can not find this sentence. Ruslik_Zero 09:43, 5 June 2009 (UTC)

    I broke it. Serendi^podous 09:47, 5 June 2009 (UTC)

  • I took initiative and done much of minor copyediting. Please check as I might have accidentally distorted the meaning. I couldn't fix "This current then moves radially away from the planet within the plasma sheet and finally returns to the planetary ionosphere long the polar field lines from the outer reaches of the magnetosphere". Please do.Materialscientist (talk) 05:49, 5 June 2009 (UTC)

    Fixed. Ruslik_Zero 09:43, 5 June 2009 (UTC)

  • The infobox states that the Magnetosphere of Jupiter was discovered by Pioneer 10 in 1973, which seems odd: As the text states, lots of reliable evidence existed before that. Materialscientist (talk) 05:40, 5 June 2009 (UTC)

    It is a matter of opinion. I think that "discovered" means measured directly. Ruslik_Zero 09:43, 5 June 2009 (UTC)

  • I do oppose deletion of my adds "Ionian (i.e. pertaining to Io)" and Jovian (i.e. pertaining to Jupiter)" by Serendipodous. Please keep in mind that most readers will not understand those terms, even though they became part of English. Materialscientist (talk) 00:21, 7 June 2009 (UTC)
    • What's wrong with Ionian and Jovian? Titoxd^{(?!? - cool stuff)} 04:47, 7 June 2009 (UTC)

      Nothing, just too many people would have to look up the dictionary :) Materialscientist (talk) 05:02, 7 June 2009 (UTC)

      No, I mean linking the terms... you get a nice tooltip when you hover over a link, it's not even necessary to click it... Titoxd^{(?!? - cool stuff)} 05:05, 7 June 2009 (UTC)

      It is software dependent (delayed on my PC); not everyone would know they should mouse-point and wait; those comments in brackets are clearer. Materialscientist (talk) 05:27, 7 June 2009 (UTC)

      They are also shown in the status bar, and they're clickable as well. The parenthetical clauses disrupt the flow of the text, IMO. Titoxd^{(?!? - cool stuff)} 05:56, 7 June 2009 (UTC)

  • More to come. Materialscientist (talk) 11:47, 4 June 2009 (UTC)
• Comments - sources look okay, links checked out with the link checker tool. Ealdgyth - Talk 19:22, 6 June 2009 (UTC)
• Support. I have been looking over this article with a watchful eye since early March, and I think it is now of FA standard. I saw it in March after being one of Ruslik's TPSers. :) ceranthor 19:32, 8 June 2009 (UTC)
• Comments I have noted several inconsistencies in the citation style. Some issues are:

• "et al." vs "et al.". (italics or not).
• Number of authors names mentioned before "et al.": The most common convention is to name only the first author before the "et al." this article almost consistently uses 3. Which would be OK if used consistently, but there are also references that list all 10+ authors.
• "full names" vs initials: Some refs list the full names while others use only initials. The article should decide on which the use consistently. (Also if initials are used decide on a format consistently ("Doe, J.W." vs. "Doe, J. W." vs. "J.W. Doe" etc.)
• Use of "and" with multiple authors: decide whether not use "and", and whether it should be precded by a "," ";" or nothing at all.

(TimothyRias (talk) 09:29, 11 June 2009 (UTC))

Fixed I think. Serendi^podous 10:10, 11 June 2009 (UTC)

You missed a couple of extra spaces. (I fixed them.) Just one more thing: The citations mix "American" and "British" styles for capitalization of titles. I usual prefer having only one of the two styles, but I'm not sure that that is generally agreed upon. (TimothyRias (talk) 10:31, 11 June 2009 (UTC))

I don't know the difference between American and British capitalisation standards. Serendi^podous 10:56, 11 June 2009 (UTC)

American: capitalize all nouns, verbs, adjectives and adverbs.

British: Capitalize only first letter and proper nouns. (TimothyRias (talk) 11:07, 11 June 2009 (UTC))

Fixed. I did keep one phrase capitalised, though, because it formed an acronym. Serendi^podous 12:00, 11 June 2009 (UTC)

Almost everything adressed. The only issue remaining is the number of authors mentioned before "et al." some refs have 2 others have 3. (TimothyRias (talk) 10:05, 15 June 2009 (UTC))

I only found one, but it's fixed. Serendi^podous 10:11, 15 June 2009 (UTC)

• Support—It satisfies the FA criteria, although I found a few pretty minor issues:
  • "Jupiter's magnetic field forces the torus to rotate with the same speed and direction as the planet's rotation." By speed, I assume this means angular velocity? Or perhaps 'angular speed' would work here?

Fixed. Serendi^podous 05:45, 12 June 2009 (UTC)

• • The illustration with the caption, "An artist concept of the magnetosphere", includes the term 'plasmasphere'. This is not mentioned in the text, so I think it needs clarification.
  • To me the statement, "...the magnetic field in the southern(northern) lobe pointing toward(away from) Jupiter," seems perhaps self-contradictory and hence confusing. It also needs spaces before the parentheses.

    Fixed. Serendi^podous 05:45, 12 June 2009 (UTC)

    I clarified the meaning of the 'plasmasphere'. Ruslik_Zero 16:44, 12 June 2009 (UTC)

  • "...seriously disturbed by its interaction with the plasma sheet" is somewhat vague. Perhaps an example would serve?
  • "A particularly interesting feature..." seems mildly PoV-ish.

    fixed. Serendi^podous 05:45, 12 June 2009 (UTC)

    I added an example. Ruslik_Zero 16:44, 12 June 2009 (UTC)

  Good stuff. Thanks.—RJH (talk) 20:37, 11 June 2009 (UTC)

Image concern as follows:

• File:Jovian magnetosphere (view from the north pole).png: reference for this diagram?

Other Images are appropriately sourced, and verifiably in the public domain or appropriately licensed. Jappalang (talk) 03:35, 12 June 2009 (UTC)

• I added a reference to the image caption. Ruslik_Zero 15:51, 12 June 2009 (UTC)

  The references for the image are preferred to be in the image page as well. I have added your reference to it. Jappalang (talk) 04:00, 13 June 2009 (UTC)

Support A shining example of a featured quality article. A good article that provides a well-balanced and informative coverage of the subject. My only minor concerns were the rewording of some minor phrases like "particularly interesting" as mentioned above but most of these earlier problems seem to have been attended to. Nice work!. Dr. Blofeld ^{White cat} 15:32, 13 June 2009 (UTC)

Thanks for support. Ruslik_Zero 16:06, 13 June 2009 (UTC)

I'm finding jargon and linking issues throughout (what's a tail sheet current?). And an inline to be resolved in the lead. Can someone please go through and make sure all technical terms are defined or linked on first occurrence. SandyGeorgia (Talk) 17:50, 16 June 2009 (UTC)

I've fixed your inline issue, but it is kinda difficult to decide what's jargon and what isn't. Serendi^podous 19:00, 16 June 2009 (UTC)

The above discussion is preserved as an archive. Please do not modify it. No further edits should be made to this page.