Wikipedia:Peer review/Epsilon Eridani/archive2

Epsilon Eridani

Previous peer review

This peer review discussion has been closed.
This topic is interesting because this is the nearest star to us that is known to (probably) have a planet. In fact there may be three or more planets, along with an asteroid belt or two. The fact that it is also a Sun-like star makes it of interest as a potential interstellar travel destination and for the possibility it may host an Earth-like planet.

Review history: This article has previously gone through PR and is a GA. It was submitted for FAC, but I withdrew it in order to update the page with the results of an expect review. There were several supports and no objections, but it did generate quite a few comments. Most of these have been resolved. The lingering concern is about the need for an image of the star, which is hindered by the lack of suitable licenses.

Please take a look and post a few comments if you have an interest. Thank you. Regards, RJH (talk) 19:02, 22 July 2011 (UTC)

• I don't have time to do a proper review (and did the GA in any case), but in terms of images you could use a crop of File:Orion above the VLT .png; I think eps Eri is visible on the left of that image. Leaving enough of the image to show where Orion is in relation might help readers understand where this star is, and how bright it is. Modest Genius ^talk 20:37, 22 July 2011 (UTC)

  Yes I think you're right. Thanks for the suggestion. Regards, RJH (talk) 21:02, 22 July 2011 (UTC)

Ruhrfisch comments: This looks pretty ready for FAC to me, here are some pretty nitpicky suggestions for improvement.

• Dab finder tool on this PR page finds one circular redirect
  • That was being caused by a NavBox. I've fixed it for the moment, but there's no guarantee it won't be re-introduced.
• In the lead, I would cut the word stories here (not just sf stories, movies and tv too). As one of the nearest Sun-like stars and a system that may harbor life,[22] Epsilon Eridani regularly appears as a target of SETI searches and proposed interstellar travel, as well as in science fiction stories.[23]
  • Fixed, I hope.
• Missing word? From 1881 to 1883, American astronomer William L. Elkin used a heliometer at the Royal Observatory at the Cape of Good Hope, South Africa to repeatedly compare [the?] position of this star with two nearby stars.
  • Fixed.
• I would add "magentic" here for clarity Although there is a high level of noise in the radial velocity data due to magnetic activity in the star's photosphere,[38] any periodicity caused by this [magnetic] activity is expected to show a strong correlation with variations in emission lines of ionized calcium (the Ca II H and K lines).
  • Okay.
• I would specifically say the proposed second planet is Epsilon Eridani c (in Circumstellar discoveries)
  • Done.
• The abbreviation "pc" for parsec needs to be spelled out explicitly
  • Okay, I tried to do this consistently.
• Do Kelvin temperatures need conversion to Fahrenheit?
  • This is covered by WP:UNITS. In short, the answer is no, because this is a scientific article. RJH (talk)
• To me Ca II sounds like it is doubly ionized (Ca 2+) The K-type classification of this star indicates that the spectrum displays relatively weak absorption lines from energy absorbed by hydrogen, plus strong lines of neutral atoms and singly ionized calcium (Ca II).
  • I know the nomenclature is a little confusing, but that is the convention in astronomy. An H II region, for example, is a region where many of the hydrogen atoms have lost their sole electrons. RJH (talk)
    • Thanks - I have a friend who is an astronomer who calls any star with lots of any element above He "metal rich" (or is it any element above H?)
      • (See metallicity.) Yes, but I'm not sure the phrase is rigorously defined. It just seems very vague to me, so I was avoiding its use.
        • 'Metal rich' would normally refer to any star with metallicity above solar. Unless you meant metallicity itself? That's certainly well defined, with Z being the fraction (by mass) of all elements heavier than Helium (X is used for H fraction, and Y for He fraction). It's almost always normalised to the solar value, in the same way as mass and luminosity. Modest Genius ^talk 16:26, 7 August 2011 (UTC)
          • I've also seen 'metal rich' being used when describing Population 1 stars like the Sun (vs. 'metal poor' for Population 2). Perhaps that's the source of my ambivalence. Regards, RJH (talk) 19:56, 16 August 2011 (UTC)
• Would it help to indicate that this star's field strength is roughly 3 orders of magnitude greater than the sun? The average magnetic field strength of this star across the entire surface is (1.65 ± 0.30) × 10−2 T,[55] compared to (5–40) × 10−5 T in the Sun's photosphere.[56]
  • I included a comparison.
• Magnetic activity section uses "this star" eight times, which seems a bit much
  • Addressed.
• I owuld at least mention the science fiction uses of the star in a sentence or two in the Potential habitability section. It is in the lead and See also, but I think a sentence or two could be added here.
  • I wasn't sure how to make a useful generalization about the science fiction topic, other than to say the star was used.
• Please make sure that the existing text includes no copyright violations, plagiarism, or close paraphrasing. For more information on this please see Wikipedia:Wikipedia_Signpost/2009-04-13/Dispatches. (This is a general warning given in all peer reviews, in view of previous problems that have risen over copyvios.)

Hope this helps. If my comments are useful, please consider peer reviewing an article, especially one at Wikipedia:Peer review/backlog (which is how I found this article). I do not watch peer reviews, so if you have questions or comments, please contact me on my talk page. Yours, Ruhrfisch _><>°^° 15:42, 6 August 2011 (UTC)

Thank you for the review. Regards, RJH (talk) 16:26, 6 August 2011 (UTC)