Wikipedia:Peer review/90377 Sedna/archive1

90377 Sedna
This peer review discussion has been closed. I've listed this article for peer review because I've done some expanding in preparation for an FA nom and was wondering if there was anything I missed.

Thanks,  Serendi pod ous  20:56, 16 July 2010 (UTC)

RJH comments&mdash;Here are a few observations that I hope will be helpful if you take this forward for FAC: Thanks.&mdash;RJH (talk) 18:03, 18 July 2010 (UTC)
 * Several places in the first paragraph of the lede contain transitory information, which may become outdated. For example, other, more distant dwarf planet candidates may yet be discovered. Likewise, somebody is likely to object to "It is currently...". I'd recommend using an As of template, or clarifying it somehow.
 * "...led to much speculation as to its origin" is passive. You might instead say something to the effect that the origin remains uncertain. You could also remove the "in fact" from a subsequent sentence as additive.
 * The statement that, "However, Sedna never comes close enough to Neptune to be affected by its gravity," is untrue. It is always effected by the gravity of Neptune. This needs to be changed to something regarding the degree of perturbation from the object's orbit. Even small perturbations can add up, under certain circumstances.
 * Sedna is far beyond Neptune's gravitational influence. -- Kheider (talk) 09:54, 20 July 2010 (UTC)
 * I believe that article is specifically referring to influencing the perihelion of Sedna, as per the Brown, Trujillo and Rabinowitz (2004) that it references.&mdash;RJH (talk) 18:47, 20 July 2010 (UTC)
 * Please clarify the first mention of IAU, rather than subsequently listing the full name and linking it there.
 * "Inuit" should be wikilinked.
 * "The name was, however,..." 'However' should be at the start of the sentence.
 * "Sedna's 200-year perihelion period" Could you explain perihelion "period" here?
 * "Sedna's precise orbital period is not yet known..." As of?
 * "It is now generally believed..." Says who
 * The "common model of the surface" values don't add up to 100%. I get a total of 59%.
 * "Amateur astronomers using advanced software and long exposures have been able to detect Sedna." This seems a trivial mention, and the listed cite has a broken link. Have they made any discoveries beyond simple detection, or does this have some other applicability?
 * In the origin section, could the text explain whether the disruptive collision of a larger body has been ruled out as a cause?
 * The names in the references section are formatted inconsistently. I see mixtures of semi-colon and comma separators, instances where it is "last, first", "first last" and mixtures of the two. Any "et al." should use italics.
 * The Elliot et al. (2006) needs a doi or bibcode.
 * Some of the external links could be trimmed, as could some of the redundant "See also" links.
 * Addition: It might not hurt to include a "fun fact" about how the Sun would appear if viewed from Sedna. Several old news stories mention that the Sun would appear like a bright star, rather than a disk. Probably could compare the brightness to that of the Moon and give an angular size comparison of some sort.
 * See File:Web print-1-.jpg. It would be nice if an admin would give the file a better name. -- Kheider (talk) 19:51, 22 July 2010 (UTC)

A few things that would make this article more polished: 18.74.1.238 (talk) 18:06, 18 July 2010 (UTC)
 * is there any better image available?
 * Sadly, our knowledge of Sedna in 2010 is kind of like are knowledge of Pluto was in the mid 1970's. commons:Category:Sedna doesn't seem to have any exciting ones that do not mislead the reader into thinking we know more about Sedna than we really do. ie: a lot of website still show Sedna with a large moon, and we now know that Sedna does not have a large spherical moon. LightBuckets has a decent image that is basically as good as the discovery image, but it is for "non-profit use only". -- Kheider (talk) 10:34, 20 July 2010 (UTC)
 * try to find a picture of the goddess after which it was named
 * "Sedna will overtake Eris as the farthest now-known spheroid orbiting the Sun in 2114": spheroid is a vague term for anybody that is not used to the astronomical jargon; either link it or explain what is the limit for having an object defined as a spheroid (is there a differentiation btw spheroid and minor planet?); also "presently-known" might be better than "now-known"
 * in the exploration section I would add an OR-ish type of information that I think would still be valuable to the article: take the best-case-scenario (i.e. perihelion in 2075) and try to estimate when would a spaceship (with the current technology, say New Horizons) have to be launched to intercept the spheroid. A rough estimation tells me it should be on the order of 25 years. This way readers would have a better grasp on the difficulties in studying such an object. Also, how long would a signal take to travel from Sedna to Earth?
 * "observed no such object orbiting the planetoid": what is the confidence interval (i.e. estimated upper limit on the diameter of this planetoid)
 * "New measurements from the MMT " change to "Newer" since 2005 is not really new anymore
 * "Observations from Chile ": be specific: what observatory(es)?
 * "lthough Sedna's 200-year perihelion period may allow its surface temperature to rise above the 35.6 K (−237.4°C or −395.3°F) boundary required for nitrogen to shift from solid to gas,[19] its deep red spectrum, indicative of high concentrations of organic material, and weak methane absorption bands suggest that, unlike similar large objects like Triton or Pluto, Sedna never forms an atmosphere": this is quite confusing: never is an overly-strong choice of word; if you mention N2 sublimation, then explicitly state that it would mean that the surface does not contain N2 (this is q bit weird though; does anybody explain the lack of N2?). Why is weak absorption of CH4 indicative of an atmospehre? Try to explain a bit.
 * I guess this paragraph is a bit confusing because it it unnecessarly succint
 * there are two 1-sentence para's in the characteristics section. try to merge them somehow
 * ah, what is the confidence interval for the perihelion and aphelion? in other words is the 975AU more like 800-1200 for a 95% CI or much tighter?
 * It is fairly solid. But since Sedna has such a long orbital period (10k years) and is currently approaching perihelion on a very eccentric orbit, the Epoch used to define the orbital elements is more important and can have a modest result on the numbers shown.  The DES using an 1990 Epoch shows aphelion at 980 AU, while JPL using a 2010 Epoch shows aphelion at 960 AU. JPL Horizons shows Sedna's perihelion to be 76.18 AU on 2076-Jul-18.-- Kheider (talk) 10:34, 20 July 2010 (UTC)
 * "The distinction is made formally, using the orbital elements (see Tisserand's parameter)." this should be explanded/explained.