Wikipedia:Featured article candidates/Tau Ceti

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 02:59, 8 October 2007.

Tau Ceti[edit]

A co-nom with User:RJHall. RJ provided all of the principal data on this star (including the minutiae of the infobox) and the general page structure almost a year ago, for GA. I decided to give it a good run over the last week because it was close to FA. The life and planet section has been expanded, the prose audited, more precise headlines introduced, and some new info added to physical characteristics. RJ has set the star referencing standard with IK Pegasi but I think this compares well—every recent paper on this body is in there, on my last digging around.

(Pics? Sorry folks, no good pics.) Marskell 20:35, 27 September 2007 (UTC)[reply]

Comment. Why is it called Tau Ceti? JHMM13^(Disc) 02:35, 28 September 2007 (UTC)[reply]

It's a Bayer designation. I added a footnote. Marskell 09:39, 28 September 2007 (UTC)[reply]
- Thank you :-). Sometimes it takes a relatively ignorant person to point out something not so obvious. ;-D JHMM13^(Disc) 15:00, 30 September 2007 (UTC)[reply]

Comment - should the 'is' be a 'would be' in "Sun is a second-magnitude star..." as no-one has ever been there to see it?cheers, Casliber (talk · contribs) 09:49, 28 September 2007 (UTC)[reply]

A dim optical companion has been observed, which is possibly gravitationally bound, but it is more than ten arcseconds distant from the primary. - erm..what? Is it a double star?...don' leave us hangin'....cheers, Casliber (talk · contribs) 09:54, 28 September 2007 (UTC)[reply]

The source: "This star has a faint optical neighbour, possibly a binary companion (Worley 1996), which has a V magnitude of 13.1 and is separated by more than 10 arcseconds from Cet, and therefore does not influence the interferometric measurement." So unfortunately we can't say with total certainty. This is Worley—a massive catalog, apparently. Marskell 10:09, 28 September 2007 (UTC)[reply]

Aha, frustating. I have combined a few stubby paras where the subject matter is not clearly differentiated between one para and the next. I regret my astronomy is not as good as others so will await Ruslik's approval before I can support on comprehensiveness but am happy with prose and flow now.cheers, Casliber (talk · contribs) 23:19, 28 September 2007 (UTC)[reply]

Comments. Article is intersting, but I have a few issues with it.

1) The article claims: "In the case of Tau Ceti, the atmospheric metallicity is roughly: $\left[{\frac {Fe}{H}}\right]=-0.50$ or about half the solar abundance.", which is wrong, because -0.50 means that τ Ceti metallicity is ${\sqrt {10}}\approx 3.1$ times less then the Solar value.

2) The 'Luminosity and variability" subsection contains phrase: "This indicates a relatively stable star with only a low level of periodic magnetic variation.", which should be removed, because it duplicates the previous sentence. The low activity actually supports conclusion that the star is old.

~~3) τ Ceti (HD 10700) was a target of radial velocity planetary searches, which also failed to discover any planets. See [1]. You should mention this fact in the article.~~

Ruslik 13:26, 28 September 2007 (UTC)[reply]

I think I took care of 2. Is it possible that your link in 3 is simply summarizing what we already have? (i.e., the Hubble '99 search.) I'm not sure if it refers to a unique search. I'll ping RJ regarding 1. Marskell 20:03, 28 September 2007 (UTC)[reply]

By now more then 200 planets have been discovered by radial velocity (spectroscopic) searches. HST has never been used for them, because it lacks necessary equipment. HST was only used for the imaging of this system, but it found nothing as the article says. So I am talking about a different investigation. [2] is actually the best source radial velocity (and other) planetary searches. Ruslik 14:28, 29 September 2007 (UTC)[reply]

"No astrometric or radial velocity perturbations have been deduced" covers the third, I think. — 24.16.105.84 17:27, 29 September 2007 (UTC)[reply]

(I think that anon is RJ.) Yes, that sentence covers the point, I think. I added one of Ruslik's links as an extra reference. The apx 1/3 point was also addressed. Marskell 14:34, 30 September 2007 (UTC)[reply]

I propose instead to add (to the planet searches section) the following paragraph:

"Tau Ceti was a target of a few radial velocity planetary searches, which have failed to find any periodical variations attributable to planets. The velocity precision reached so far is about 11 m/s measured over 5 year time span. This result excludes the presence of hot Jupiters, and any planets with minimum mass (M·sini) of one Jupiter’s mass or more and with orbital period less then 15 years."

The radial velocity searches seem to have excluded any giant planets (not only brown dwarfs and hot Jupiters) closer then 5 au. Ruslik 18:22, 30 September 2007 (UTC)[reply]

Yes, assuming that the inclination is not close to 90° from the line of sight. — RJH (talk) 16:20, 1 October 2007 (UTC)[reply]

Support. This is a comprehensive article, which deserves to be Featured. I actually inserted the paragraph mentioned above myself. Ruslik 12:16, 1 October 2007 (UTC)[reply]
Support - (Otto-speak) I'm with the Rusklik dude. cheers, Casliber (talk · contribs) 07:36, 3 October 2007 (UTC)[reply]

Hey thanks. I got sidetracked last night. Marskell 13:02, 1 October 2007 (UTC)[reply]

Support - Great article, especially the explanation of radial velocity for someone who doesn't understand astronomy (not me, I have some astronomy knowledge from 2 astronomy classes at college). In the sentence "The velocity precision reached so far is about 11 m/s measured over 5 year time span" - the 11 m/s should also list the velocity converted to Imperial units for the Americans who don't understand metric. Royalbroil 05:46, 4 October 2007 (UTC)[reply]
- There was a consensus somewhere (in MoS?) that scientific articles should just stick to scientific notation without including Imperial units. — RJH (talk) 20:56, 4 October 2007 (UTC)[reply]
  - Yes, that was at WP:MOSNUM (which hopefully has stabilized now). SandyGeorgia (Talk) 20:21, 6 October 2007 (UTC)[reply]

Support, looks good. One question, is it custom in Astronomy articles to use all that punctuation with the author list on journal articles? Have a look at Asperger syndrome to see the consistent punctuation on authors returned by Diberri's tool for PubMed journal references on medical articles—they're just cleaner looking without all those periods and semi-colons. SandyGeorgia (Talk) 20:21, 6 October 2007 (UTC)[reply]

The semi-colons are probably my fault (I think R.J. just uses commas); I find it good to separate authors with initials. But I can look. Marskell 20:29, 6 October 2007 (UTC)[reply]

Diberri's tool (and Pubmed) return like this, for example:

Arndt TL, Stodgell CJ, Rodier PM (2005). ...

so medicine FAs tend to use that format consistently. Just a thought to make your refs purdy. SandyGeorgia (Talk) 22:54, 6 October 2007 (UTC)[reply]

'author= | coauthors=' generates a semicolon from the template, unfortunately; if not, I probably wouldn't have adopted it. Marskell 06:36, 7 October 2007 (UTC)[reply]

I use semi-colons to separate a long list of authors per the seeming convention at NASA ADS. See for example: http://adsabs.harvard.edu/abs/1992A&AS...95..273C I know there's different conventions for how to do that, depending on the field. — RJH (talk) 15:48, 7 October 2007 (UTC)[reply]

The above discussion is preserved as an archive. 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.