Talk:List of stars with confirmed extrasolar planets

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Contents 1 planet ordering 2 doubtful planets? 3 naming system 4 Planet naming 5 Please add Table Sorted by Distance from Earth 6 Earth orbital radii vs astronomical units 7 Sort Order and Accuracy of Masses 8 14 Herculis and OGLE-TR-111 9 Missing planets 10 Fusing vs. Normal stars 11 Science Fiction 12 Mu Arae 13 Links 14 Vega is gone 15 Distance? 16 Adding Discovery Years 17 Naming conventions 18 Free floating planets 19 "Confirmed?" 20 Fusing planets 21 could someone make the list sortable 22 Brown dwarfs in the list 23 need to catch a plane, but... 24 Distance removal 25 Removal of HD 33636 26 Mapping in Progress 27 Requested move 27.1 Survey 27.2 Discussion 28 Data for HD5319 and HD75898 planets inconsistent with http://www.arxiv.org/pdf/0708.0832 29 Semi-major axes of the candidate exoplanets 30 Free-floating planets 31 Comparison to Earth 32 HD 154345b

[edit] planet ordering

Is there any logic to the organization of these lists? They seem random to me - but am I missing something? Shouldn't the stars be in alphabetal order or something? The Singing Badger 21:03, 23 Nov 2004 (UTC)

Multiple systems are sorted alphabetically, and single planets by increasing mass (because that's the most important attribute of the planet). Jyril 14:30, 27 Nov 2004 (UTC)

I've changed my mind. Maybe sorting by name is the most sensible way to list the planets.--Jyril 02:20, 18 December 2005 (UTC)

[edit] doubtful planets?

Should doubtful planets be on this page at all? Perhaps they should go in hypothetical planet instead. 132.205.15.43 05:06, 30 Nov 2004 (UTC)

Solar system planets on hypotethicals page are mostly just hypothetical; on the other hand these doubtful planets have been false detections. Maybe they should have a list of their own as List of unconfirmed extrasolar planets (after all, this is a list of confirmed extrasolar planets). Jyril 15:45, Nov 30, 2004 (UTC)

I've moved the list to hypothetical planet, since they are definitely not confirmed planets, and appear to be on the way to being disproven planets. Hypothetical planet article allows for unconfirmed and disproven planets, according to what it says. 132.205.45.155 01:11, 1 Dec 2004 (UTC)

[edit] naming system

Why are most of these planets "b"? What about "a"? What do the letters indicate? Ubermonkey 18:29, 22 Mar 2005 (UTC)

A is the star itself; B and C and so on are given to subsequent orbiting objects - hence the planets are generally B. I've added a bit to the article to explain that. Worldtraveller 18:35, 22 Mar 2005 (UTC)

In a binary or multiple star system the component stars are named A, B, etc. For single stars the A is not used. The planets orbitting each star are b, c, etc. in the order they were discovered. (a is never used.) See HD 189733 for an example.--Mu301 05:20, 29 January 2007 (UTC)

[edit] Planet naming

• see Wikipedia_talk:WikiProject_Astronomical_objects#Extrasolar_Planets; there needs to be a default convention on naming the articles. 132.205.15.43 05:14, 25 Mar 2005 (UTC)

[edit] Please add Table Sorted by Distance from Earth

A frequent question is what is the distance from earth for each of these extra-solar planets. Currently you have to look up each star, make your own list, then sort them. Can you please add list of extra-solar planets sorted by distance from earth?

I don't think that would work. You would have multiple copies, all of which must be updated. Maybe sorting by name is the best way because in that way finding the right planet is easier.--Jyril 02:19, 18 December 2005 (UTC)

Understood. Is there an external sortable database of extrasolar planets which you could provide a link to? That way people wanting to sort by any criteria could do it, and you wouldn't need multiple redundant tables. I looked around and found a few, but not sure which would be best:

http://planetquest1.jpl.nasa.gov/atlas/atlas_index.cfm (but doesn't allow querying or sorting by distance from earth)

A link at the bottom of this article: Extrasolar planet says | searchable dynamic database of extrasolar planets, but it's in German. Another external link in that article says: | Extrasolar Planet XML Database, but it's unavailable.

This is one I found that allows sorting by all criteria, and not sure if it's the best one? Joema 03:16, 18 December 2005 (UTC) http://vo.obspm.fr/exoplanetes/encyclo/catalog-main.php?mdAff=output#tc

I also agree that the sorting by distance from Earth will not work.

• The distance from Earth for most stars is not known with absolute precision and thus the distance cannot be accurate.
• Most astronomical catalogues sort their entries by right ascension because it can be measured accurately.

To understand this issue better, I include a brief primer on how these two measures are quantified. Position is measured simply by observing the location of the star in the sky, which can be measured to a tenth of an arc second fairly easily. On the other hand, measuring the distance to a star requires knowing the parallax of the star which is how much the position of the star changes through the year. This requires measurements of the position of the star with a much greater accuracy than the position measurement.

Most astronomical catalogues sort their entries by Right Ascension.

--  B.d.mills  (Talk) 01:38, 16 April 2006 (UTC)

[edit] Earth orbital radii vs astronomical units

The table header lists the planet distance in multiples of Earth's orbital radius. Surely it would be better to write this number in terms of Astronomical unit, especially since the Earth's orbital radius is slightly greater than 1 AU, though at the current level of knowledge this is more a stylistic point as the discrepancy is less than the accuracy to which we know the orbits. Chaos syndrome 19:35, 2 January 2006 (UTC)

[edit] Sort Order and Accuracy of Masses

I'm not satisfied with the ordering of these lists and the accuracy of the imformation. The stars are ordered alphabetically by star name from various star catalogues for multiple star systems, and by increasing mass of the planet for single star systems. This is unsatisfactory for several reasons.

• For multiple-planet systems, the choice of catalogue is chosen arbitrarily. Each star appears in multiple catalogues. Finding a particular star can be problematic if one knows it by its reference in one catalogue and the name appears in the list under another catalogue name.
• For single-planet systems, ordering by mass is incorrect because in most cases the mass of the planet is not known with any degree of accuracy. Refinements in the estimated mass of various planets are likely. The masses also include an error range that is not listed.
• Sorting the different lists by different criteria is confusing. The two lists should be sorted the same way.

I propose that the lists be modified as follows:

• Include for each planet the error range for the measured mass, example 1.30 ±0.15 MJ
• Include the Right Ascension and Declination of each star, in Epoch 2000.0 co-ordinates
• Sort all stars by Right Ascension

Most astronomical catalogues sort their entries by right ascension (NGC, HIP, HD, Flamsteed etc) so this sort order would be logical to use here.

--  B.d.mills  (Talk) 01:27, 16 April 2006 (UTC)

I agree the current system is unsatisfactory. Sorting by right ascension sounds reasonable, or maybe we could to what the Extrasolar Planets Encyclopaedia does, and sort by period of the innermost planet? Chaos syndrome 12:44, 16 July 2006 (UTC)

This is not a primary reference for astronometrcial data. It should be sorted in a manner that a lay person may want to view it. Sorting by Right Ascension will not be helpful to the average person looking up exoplanets. This would almost certainly look like a jumbled list with no order to such a person. I think sorting by mass works for the general audience, even if it is an estimate, for single planet systems. I agree sorting by name is not good for multiplanet systems. We can probably sort first by number of planets in a system, then perhaps sort by total estimated minimal mass of planetary bodies? Zzzzzzzzzzz 20:21, 3 August 2006 (UTC)

Problem is that the actual masses are unknown in the majority of cases, which makes sorting by mass rather arbitrary. Sorting by mass also isn't helpful for someone trying to find a specific system in the list. Sorting by right ascension at least gets the HD numbers (which comprise most of the star designations) in the right order, and doesn't suffer from the problems that alphabetical ordering has. As has been pointed out, the catalogue we use is fairly arbitrary. In addition, some stars - e.g. 55/Rho¹ Cancri and Iota Horologii/HR 810 are commonly referred to by two names in the literature, which would affect sort order. I think if we're going to avoid arbitrariness in the sort order of the table, the choice basically comes down to period or right ascension. Ideally of course we'd have nice clickable "sort by this column" buttons and an interactive table, but like that's ever going to happen. Chaos syndrome 21:26, 3 August 2006 (UTC)

At any rate, I think that the multiple planet section should first be divided by total number of planets, and then ordered within that. Zzzzzzzzzzz 23:54, 4 August 2006 (UTC)

[edit] 14 Herculis and OGLE-TR-111

Should 14 Herculis and OGLE-TR-111 be in the list of multiple planet systems? The second planet in both systems has not been confirmed, and this is a list of stars with confirmed extrasolar planets. I'd be inclined to put them in the single-planet systems list with a note to the effect that there is an unconfirmed second planet. Chaos syndrome 21:28, 17 April 2006 (UTC)

[edit] Missing planets

According to The Extrasolar Planets Encyclopaedia, we should have a total of 202 planets (the figure of 200 listed on the site omits the two free-floating planets). We seem to have the correct number of planets in multiple-planet systems, and the right numbers of brown dwarf, pulsar and free-floating planets, which suggests the missing planets are from the huge list of single-planet systems, which makes finding the missing entries rather tedious.

Maybe it would be easier to re-generate the tables using the Extrasolar Planets Encyclopaedia (there are XML or text output options there which should be easy to handle in a program). The problem with this approach is that some articles use orbital elements from the Catalog of Nearby Exoplanets, which in some cases differ significantly from the Extrasolar Planets Encyclopaedia (a notable example are the elements for 55 Cancri).

Any comments/suggestions? Chaos syndrome 20:35, 30 July 2006 (UTC)

I checked this several months ago and there was several unpublished planets on the Extrasolar Planets Encyclopaedia site at that time i.e. HD 11964[1] Mike s 21:35, 30 July 2006 (UTC)

I don't think that's the reason for the discrepancy, as far as I can tell, the unpublished/unconfirmed planets aren't counted in those totals. Chaos syndrome 21:45, 30 July 2006 (UTC)

I just checked the list of planets orbiting around Pulsars and found that PSR 1257-17 D is missing. I would add it to the table but I don't know how to do that, so if someone could add it I'll delete this comment afterwards. --alias--

I removed PSR 1257+12 D since it is not confirmed, and even if it was it is thought to be a cometary object (i.e. not a planet). Chaos syndrome 10:13, 5 August 2006 (UTC)

Those planets can be placed in the List of unconfirmed exoplanets. 132.205.44.134 23:53, 13 November 2006 (UTC)

[edit] Fusing vs. Normal stars

Although the current title of the typical stars is accurate, but maybe using "normal" (as opposed to sub-stellar objects and stellar remnants) instead of "fusing" in the title would be more accessible to regular user?--JyriL ^talk 16:45, 3 August 2006 (UTC)

Well, it beats the horrifically inaccurate "main sequence stars" we had before. Not sure about using "normal" though... why is a brown dwarf abnormal, and not a giant star? Some of the stars have letters describing various peculiarities in their spectra, others are variable stars of one sort or another. It is (at least from my point of view) rather dubious calling such stars "normal". Chaos syndrome 18:44, 3 August 2006 (UTC)

Alternatively, we could get rid of the free-floating objects and 2M1207b since their planetary status is debatable (which probably means they aren't "confirmed planets", rather "confirmed substellar objects"), lump the pulsar planets in with the rest of them and avoid trying to think of a heading which seems to be defined by what it is not ("stars which are not pulsars, white dwarfs, black holes, brown dwarfs, other objects which it is fashionable at the time of writing to have a prejudice against..."). Maybe we should prune the list to get rid of objects >13 Jupiter masses as well. Chaos syndrome 21:38, 3 August 2006 (UTC)

In fact, we should probably get rid of the free-floating planets anyway, they don't fit to well with the "stars with" bit of the title. Chaos syndrome 21:47, 3 August 2006 (UTC)

Let's keep only sections "Multiple planet systems" and "Single planet systems". Pulsar planets could be moved into own article (List of pulsar planets). Various sub-brown dwarf objects could be moved into one list as it seems that both singles and binaries are common. What comes to >13 M_J objects, I'd keep them if they're part of a planetary system (as there's possibility that they may have formed like planets). I might also keep objects that have lower bounds deep in the planetary regime.--JyriL ^talk 22:17, 3 August 2006 (UTC)

Sounds good to me. We could also start a List of planemos or something for the free-floating objects and 2M1207. Chaos syndrome 22:21, 3 August 2006 (UTC)

I would not move Pulsar Planets off onto another list, as there are only 4, so it's not alot, and this list would be prejudicial against pulsar planets (like the general media is prejudiced) as a result. It seems as though the general media don't know pulsar planets even exist, and we would further that misconception by bifurcating along the lines of whether it's a normal star or not. Zzzzzzzzzzz 00:06, 4 August 2006 (UTC)

A solution would be to integrate pulsar planets into the main list of single and multiple planets. Then a separate sublist (list of pulsar planets) makes sense. Zzzzzzzzzzz 00:08, 4 August 2006 (UTC)

No, they should not be combined. The planets around PSR 1257+12 are very different from planets around normal stars. Also, pulsar planets doesn't fit the name of this article (BTW, why it's not List of confirmed extrasolar planets?)--JyriL ^talk 09:25, 4 August 2006 (UTC)

Then if you eliminate non fusing stars, you'd have to rename the article. And as it's a list of stars with planets, it can't be very different, since it's a star with some planets. We don't discuss the composition of planets in the list. A pulsar is a star, if a pulsar has planets, and they've been confirmed, they fit the list. 23:52, 4 August 2006 (UTC)

Another suggestion, how about making a List of confirmed planets and putting Sol system into the list? Chaos syndrome 10:18, 4 August 2006 (UTC)

We could just rename this article to be that. Sounds good. 23:52, 4 August 2006 (UTC)

[edit] Science Fiction

Since there are suspected "rogue planets", the Sci-Fi writers would literally have a field day. Here's a sample: "At 10 pm, GMT, the scientists have found a rogue planet entering the Solar System. It is the size of Jupiter, has two Earth-like satellites in orbit." Later on, as the story progresses, society fails as chaos reigns. Later on, the new arrival settles in Earth's orbit, with three Earth-like satellites in orbit, one of which that had evidence of a intelligent civilization on it, was a "independent" planet before the alien planet arrived and taken it as another satellite. The sky now has 1/2 of it occupied by the alien planet on most nights, eclipses are that the Earth is inside the shadow, the sky shows three planets in it, two satellite planets, one massive Jovian planet, all as cresents. This could go on and on. Martial Law 07:28, 24 August 2006 (UTC)

[edit] Mu Arae

We should probably have a note about the fact that we are using the designations from Gozdziewski et al. (2006) rather than from Pepe et al. (2006), who are using a proposed new designation system based on order of characterisation of the planets, rather than discovery, even though we are using the elements from Pepe et al. (2006). Chaos syndrome 19:10, 30 August 2006 (UTC)

[edit] Links

Can we link all of the planets to their articles, or their red links, so articles can be written? Do we have a naming convention we are going by. I would suggest NASAs New World Atlas or the Extrasolar Planets Encyclopedia. Anyway, if no one is opposed, I will go ahead and link those soon. A mcmurray 06:49, 5 November 2006 (UTC)

Around April 2005, a de facto naming convention was arrived upon: Wikipedia_talk:WikiProject Astronomical objects/Archive 1#Extrasolar Planets.

There is currently a proposal for a naming policy: Wikipedia:Naming conventions (astronomical objects)#Exoplanet (Extra-solar planets)

132.205.44.128 05:13, 13 November 2006 (UTC)

[edit] Vega is gone

In cleaning up the table-breaking triple-Vega mess, 68.252.236.172 seems to have gone to the other extreme and deleted Vega from the list completely. I personally don't feel confident enough to mess around with stuff that isn't a standard paragraph-style text, so I'm calling everyone else's attention to this matter instead.

There are no known planets around Vega. Clumps in its dust disk suggest that it may have planets, but the evidence is less convincing than is the case with Beta Pictoris or Epsilon Eridani, for example.--JyriL ^talk 11:35, 25 December 2006 (UTC)

[edit] Distance?

Someone please add a column to the table giving the approximate distance of each of these stars from Earth? That's something even laymen would be interested in. --SECurtisTX 15:46, 11 December 2006 (UTC)

Generally, if you click on the Star Name, you can get the distance. --Nintenfreak 01:12, 18 December 2006 (UTC)

[edit] Adding Discovery Years

Can you add years of discoveries of planets to every star/planet rows [lines] under in the Discovery Year column please. Cosmium 22:37, 10 February 2007 (UTC)

This is in progress, and about 1/2 finished.--mikeu 16:54, 14 February 2007 (UTC)

[edit] Naming conventions

I changed the paragraph on planet naming to the text given at Astronomical_naming_conventions#Designations for extra-solar planets because: 1) The system commonly used is not an official (IAU) designation, and 2) The star itself is not designated by 'a'.

If there are multiple stars in the system, they are designated with uppercase letters: ie. HD 41004A and HD 41004B. But, if there is only one star it is simply HD 38529 (without an 'A', and esp. without an 'a')

As planets are discovered they are named with lowercase letters, starting with 'b'. So the star HD 38529 has a planet named HD 38529b. The two stars HD 41004A and HD 41004B each have a planet, and they are named HD 41004Ab and HD 41004Bb.

--mikeu 16:54, 14 February 2007 (UTC)

The designations of planets should start with 'a' because it is the first letter of the alphabet. The lower case letter stands for planetary mass that orbits the star. Stars shouldn't contain a lower case letter because stars are more inclusive than planet. So, star that uses capital letter is more inclusive than planet that uses lower case letter.

If any of the planets have satellites, we use numbers after the star and planet designations. For example, HD 28185 b has a Earth-like satellite, the designation of satellite is HD 28185 b1 or it should call HD 28185 a1 as you read in above paragraph. BlueEarth 16:16, 24 April 2007 (UTC)

The names used on Wikipedia should follow the common naming conventions that are in widespread use. The system that I described is used in peer reviewed astronomical papers and also in quotes from astronomers in the news. It doesn't matter if it makes sense to us, we should just report the names that are accepted. Inventing our own nomenclature is against Wikipedia policy.--mikeu 17:58, 25 April 2007 (UTC)

[edit] Free floating planets

The Free floating planets info should probably be moved, since:

• There is only one item and "it doesn't appear to orbit a star" which contradicts the stars with in the title of the article
• "suspected" contradicts the confirmed in the title of the article
• Extrasolar planet excludes free floating because, even if confirmed, it would not meet the working definition of a planet. See Definition_of_planet#Extrasolar planets and brown dwarfs for details.
• Some astronomers [2] consider it to be a brown dwarf star.

Any ideas on the best place to move this too? The list could be expanding with two other (unconfirmed) planets at [3]. --mikeu 22:35, 18 February 2007 (UTC)

I think this should be removed if the list is to remain a list of stars with confirmed extrasolar planets. This planet also does not seem to be included in the running total number of exoplanets at http://exoplanet.eu/catalog.php . This is the source we're using on the extrasolar planet article so for the sake of internal consistency the total cited in the intro to this article should be reduced from 247 to 246 (as of July 2007) and the section on free floating planets removed. If nobody objects I'll do this shortly.

--DoktorDec 13:57, 18 July 2007 (UTC)

[edit] "Confirmed?"

In what sense are these exoplanets "confirmed?". For instance, HD 187085 b was detected by one group, but no other group has independently confirmed it. On the other hand, the group that made the detection has an excellent track record, being without a single mistake in over 100 planet claims. So perhaps the word "confirmed" is not the right one? Maybe "likely"? "Solid"? "Strong"? There is a peer-reviewed Catalog, a Table, and an Encyclopedia of exoplanets all maintained by professional astronomers, perhaps they could be used as a referee? Enfolder 05:43, 23 February 2007 (UTC)

[edit] Fusing planets

I've been BOLD and got rid of the term 'fusing' stars which I found completely confusing. I hope that's okay. Chrislintott 12:07, 3 April 2007 (UTC)

[edit] could someone make the list sortable

The list can be made sortable like this one List of Criterion Collection releases --Ted-m 21:52, 11 April 2007 (UTC)

Done. I had to remove the rowspans for the sort to work (otherwise things look quite odd when you sort) - I carefully duplicated each existing rowspan to each of the rows it spanned over and added a comment (<!-- rows: x -->) so you can still locate them. Tested the sorting and it works ok for all columns except "Planet Mass" (the ">" symbols are sorted to the bottom, not a big problem). Zarius^т 04:12, 19 April 2007 (UTC)

[edit] Brown dwarfs in the list

Why does the list of extrasolar planets around normal stars include objects with over 13 Jupiter mass? Brown dwarfs are not planets. Only Planetary masses I–V can be in the list. The upper mass limit for planets is 13 M_J. You should remove every brown dwarfs from the list of planets around normal stars and move to the list of brown dwarfs. BlueEarth 03:44, 13 May 2007 (UTC)

[edit] need to catch a plane, but...

can someone please add HD 147506 and XO-2? —The preceding unsigned comment was added by Nickshanks (talk • contribs) 08:12, 2 May 2007 (UTC).

[edit] Distance removal

I note that I am very displeased by the removal without a reason of the distance of the planet to the Solar System. While most of the distances are within some uncertainty, it helps a reader to "place" the planetary system. That is also the reason why specific articles give the "distance" in their fact boxes rather than Constellation. I would ask user BlueEarth to explain this removal. Themanwithoutapast 22:22, 21 May 2007 (UTC)

OK! I will suggest you to add apparent magnitude and distance ( which are most common datas for stars) columns, but do not remove constellation column. BlueEarth 16:13, 22 May 2007 (UTC)

Honestly, I do find the way the changes were made and this response rather confusing. First "distance" was replaced by the "constellation" column and now you suggest to add it back by hand, but not remove the constellation column - which of course would take much more time than just revert to the last good version. As to apparent magnitude, I do not see what that would add to this list, which gives specifics about exoplanets - their distance from Earth is one of their characteristics, the apparent magnitude of their host stars is not. I think to be fair, the person who admits he made a mistake deleting information from an article and who adds new information which makes it impossible to just revert the deletion without also deleting the new added information should add back the original deleted information, otherwise a revert to the last good version would be warranted (in which course the constellation column would necessarily be reverted as well). Themanwithoutapast 20:14, 22 May 2007 (UTC)

Distance is good because it places planetary systems and host stars from Earth or solar system, thus it is one of the coordinates along with right ascension and declination. Of course, adding distance column is fine, but it should all have digits to nearest hundreds. For this precision of distance, see the website: [4]. I like the distance in parsecs better but you like light years better. If you want distance in light years, multiply parsecs shown in that website by 3.2616. You can go ahead!!! BlueEarth 21:49, 22 May 2007 (UTC)

Can somebody please move distance column from rightmost after the discovery column to between declination and spectral type columns. BlueEarth 18:31, 31 May 2007 (UTC)

[edit] Removal of HD 33636

Should HD 33636 be removed from the list of extrasolar planets because the Geneva Observatory had removed this planet from the list because the astrometric data shown that this companion is a low-mass star while The Extrasolar Planets Encyclopedia did not. BlueEarth 21:34, 22 May 2007 (UTC)

[edit] Mapping in Progress

I am working on a celestial equatoreal map of 236 confirmed extrasolar planets, 2880x1440px, 8 px per 1°. (huge gif) (also older animated version)

I started with the Tycho8.tif Star map from here, which is free to use "Courtesy NASA/JPL-Caltech.", added a Celestial coordinate system, ploted all 236 confirmed extrasolar planets with excel and labeled them with flash. Now I add more constellations and fix some errors...

It is incomplete and still (in)accurate to ~4 px, hopefully I scaled and converted all coordinates correctly. --Ollj 17:32, 14 June 2007 (UTC)

Is this of any use here or is it just too big or ugly?

Does anyone have a constellation map overlay for this?

I do have constellation map with only borders or boundaries and names. BlueEarth 17:49, 14 June 2007 (UTC)

Where? http://imageshack.us/ for hosting. Ascensions should be parallel, same distances in all Declinations are better. Separate images for lines, borders and mames preferred.

Any suggestions for content, contrast, transparency or errors?

[edit] Requested move

It was requested that this article be renamed but there was no consensus for it be moved. --Stemonitis 16:31, 2 August 2007 (UTC)

[edit] Data for HD5319 and HD75898 planets inconsistent with http://www.arxiv.org/pdf/0708.0832

There are planets mentioned for HD5319 and HD75898, but the periods, axes and eccentricities do not match the table in the preprint ... what's going on?

More data points, refined orbits? — JyriL ^talk 14:40, 8 August 2007 (UTC)

[edit] Semi-major axes of the candidate exoplanets

These, as is already the case with the masses, should be preceded by '>' symbols, as they are a function of the inclination, and the inclinations are not known, as the objects are not transiting. They are therefore lower limits. As the objects are not transiting, and are therefore likely to have inclinations of less than 80 or so degrees, the quoted values in the candidates table cannot be the true semi-major axes, that is, not only are these the lower limit semi-major axes, they are also unlikely to be the real values if no transits have been found, although admittedly it is possible that some of the objects may be caught with a transit at some point. 81.129.250.131 19:13, 2 September 2007 (UTC)

That's true: since all we have are periods, rearranging Kepler's third law for a massive secondary gives:

and since the companion mass M_c is unknown: as you say, the unknown inclination comes into play here, the semimajor axis is unknown. However, the minimum masses of the objects are low, so except for very small inclinations, the mass of the star dominates in this expression, so it is likely to be close to the value determined. The increase is further damped by the cube root dependency. For example, supposing the mass of the planet turned out to be the same as the star (unlikely, since such an object would probably be luminous enough to be detected as a spectroscopic binary unless it is a white dwarf or something like that), the semimajor axis increases by only 25% from the case where the planet has negligible mass and we take M_c→0. So yes, strictly your argument is correct, but the discrepancy is unlikely to be significant in relation to the error bars on the minimum semimajor axis value. Chaos syndrome 23:37, 3 September 2007 (UTC)

Ah, there's a slight problem with my analysis there - to do it properly I should consider the inputs as velocity half-amplitude, orbital period and stellar mass. That will change things, but I don't have time to do the working right now. Chaos syndrome 08:10, 4 September 2007 (UTC)

[edit] Free-floating planets

I removed free-floating planets because all of these objects are not confirmed and does not orbit any star. The title of this article talks about confirmed planets that orbit the stars, brown dwarfs, and stellar remnants. BlueEarth 21:55, 2 September 2007 (UTC)

Put it back. It's still a planet sized object, and as there is no link to a page that talks about such bodies, this is a good a place as any. Who suddenly died and made you the IAU anyway, huh? Just because a bunch of short sighted scientists didn't think about free-floating planets, does that make them any less planet like?--130.74.235.201 16:06, 5 September 2007 (UTC)

No, they shouldn't go back into this article. This is a list of stars with confirmed extrasolar planets, not a list of extrasolar planets. Since the free-floating planets (if indeed they are planets, but I'm not going to go into that) do not orbit a star, we can't list their stars, so they don't belong here. I suggested moving this page to something a bit more accommodating (see above), but people didn't like the suggestion . Chaos syndrome 17:35, 5 September 2007 (UTC)

Then maybe what the article is called needs to change. --4.231.83.104 22:59, 2 November 2007 (UTC)

Maybe List of free-floating planets BlueEarth 23:14, 2 November 2007 (UTC)

[edit] Comparison to Earth

I think most of the readers will want to compare the mass of the planets with Earth's mass, not Jupiters. The semimajor axis is already compared to Earth's, because of the unit used. Even if comparing the mass to Earth's mass means bigger numbers I think it is much more useful. Or at least we should have both columns. As an alternative, I wanted to add -for comparison purposes- Earth to the list, but it was removed. I still think it would have been useful. The current information is hard to handle if one has to consult a separate page with Earth's data.-Paul- (talk) 21:12, 11 February 2008 (UTC)

[edit] HD 154345b

The parameters for this planet could do with updating... seems to be a Jupiter-analogue in a circular orbit. See The Jupiter Twin HD 154345b and the Extrasolar Planets Encyclopaedia entry. The HD 154345 and HD 154345 b articles need an update too. 131.111.8.96 (talk) 09:55, 12 March 2008 (UTC)