No, the IAU does NOT officially name planets

UwinguLogo-v2.pngThe IAU has issued a statement regarding the naming of planets by a group called Uwingu that is misleading or inaccurate in several ways.  Reading it, one could be forgiven for coming away believing that the IAU has given official names to planets, that these names can be found at, and that the commission responsible for this process has refused to consider Uwingu's names.  All three implications are absolutely false.  

The IAU states "In the light of recent events, where the possibility of buying the rights to name exoplanets has been advertised, the International Astronomical Union (IAU) wishes to inform the public that such schemes have no bearing on the official naming process....  they will not lead to an officially-recognised exoplanet name, despite the price paid or the number of votes accrued.

This is misleading for several reasons:

1) Contrary to the press release's implication, the IAU does not name planets.  
In the 20 years since the discovery of exoplanets, the IAU has never officially named any of them. There is not even an official scheme for binary stars, or an official definition of an exoplanet!  (There are recommendations and conventions for both, but these do not carry the official weight of an IAU definition, which is what the press release implies.  For instance, the oft-used 13 Jupiter mass threshold for planet-hood was endorsed by an IAU Working Group as a useful working definition, but it is not "official".  The planet definition that killed Pluto explicitly applies only to Solar System objects.)

2) Contrary to the press releases's assertion, there is no "official naming process." 
As another part of the IAU statement makes clear, the IAU may establish one in the future through its Commission 53.

3) Contrary to the press release's assertion, Commission 53 has not foreclosed the possibility of using Uwingu's names.  
Since there is no official process, there has been no decision about what names to use.  Thus, there is no reason that the Uwingu database could not be used in a future process established by the IAU.  That decision is up to the members of Commission 53, not an IAU press agent [Update: or any other signatory of the press release].  In fact, I'll bet the members of Uwingu, given their prominent status in the astronomical community, will ask the members of Commission 53 to use their database as a source of potential names. 

4) Contrary to the press release's implication, the press release does not and cannot describe official IAU policy. 
IAU policy is determined by democratic vote of its commissions and General Assembly.  Neither has endorsed any nomenclature for planets, much less the assertions of the press release. The IAU statement is thus the product of a rogue press agent release*.  I know this because I have contacted a member of Commission 53 and learned that they were not consulted for or even informed of this press release before it went out, and that the commission has not established a naming process since it met in Beijing in 2012.

5) Contrary to the press release's implication, Uwingu is not actually promising to give official names to or to sell naming rights to specific planets
The press release refers to a project by Uwingu to nominate names for astronomers to use to name exoplanets.  Uwingu is a non-profit organization, founded by scientists, dedicated to funding science, and is trying to raise money and awareness of exoplanets.  

The Uwingu project in question does not promise "rights to name exoplanets".  It is compiling a database of names that astronomers, including those in charge of nomenclature at the IAU, might use to name exoplanets.  This is quite distinct from scams "novelties" like the International Star Registry who claim to allow you to "officially" name a particular star.  (Today, that registry is careful to point out astronomers will not use your name; in the past they have done everything they could to imply the names would be official.)

There is an Uwingu contest to name one particular planet -- alpha Centauri B b.  They post a letter by that planet's discoverer, Xavier Dumusque, endorsing this contest.  This is not a meaningless gesture -- the discoverer of asteroids, for instance, can nominate an official name according to the official IAU naming process.

That said, I think that Uwingu should make it much more clear that the IAU could establish such an official naming scheme in the future, and that if it does so it is under no obligation to use Uwingu's names.  But the IAU's press release goes far beyond this caveat.

Finally, and this is where things get personal:  the press releases states:
"A catalogue of the exoplanets discovered, with their officially assigned catalogue designations, can be consulted in the Extrasolar Planets Encyclopedia ("

Let's be clear: is NOT an "official" list of exoplanet names, or of exoplanents. Comparison with other lists, such as mine at or the Exoplanet Archive reveals it contains many planets that are not on those lists.  This is because those planets have never been subject to peer review, or that their very existence is dubious.  The IAU has never officially defined any list, any planet names on any list, or the process by which those planets would appear on those lists.  In fact, those times the IAU has given quasi-official status to a list many years ago (for instance, here), they did NOT use the list at

This is not to disparage  it is an invaluable resource that my group uses on a daily basis, and the astronomical community is in debt to Jean Schneider and his team for their hard work on that site.  But is not an official arm of the IAU, and it does not contain a perfect list of exoplanets.

I hope the IAU issues a clarification on all of these points.

OK, glad I got that off my chest. :)

*[Update 2: My original use of the phrase "rogue press agent" improperly implied that I believed the press agent acted without the authority of the IAU General Secretary or the Commission President.  I did not mean to imply that or to insult Mr. Christensen, and I apologize.  "Rogue" referred to the fact the assertions in the press release did not reflect any vote by the relevant committee or by the General Assembly.]   

[Update: Uwingu is apparently not actually a nonprofit; I fact-checked that item before adding it (it was not in the 1st version of that post) but now cannot find the source. The website does say that Uwingu is a for-profit.  Still, my point was not so much to praise Uwingu, which I have no involvement in and I have not contributed to, but to point out the IAU's lack of due process. As for caveat emptor, I know Geoff Marcy, and Alan Stern is a reputable scientist with a true passion for this stuff. Profits go towards science and education, and the Twitter feed asserts that Uwingu team members do not receive salaries. Of course, this proves nothing, but given that I know the people involved I'm sure it's not a scam.]


I agree with the above. There is a deeper issue here though with the whole concept of 'official' which implies a society which defers to scientific experts - which is not the one we live in in the 21st century. I am curious to what extent the IAU's decisions have real *legal* status under the civil laws of its member countries? If you are not a professional astronomer trying to publish in ApJ (where editors can enforce the authority of the IAU) isn't it more natural to consider the editors of Wikipedia as more 'official' than the IAU?

I am not saying it's a good thing, I just think that by failing to engage, and to weight the input of the public as well as the input of commission members the IAU risks being ignored in the long run as the sources of authority in our civilization shift away from traditional intellectual elites..

I know I've ranted about this before, but I am stuck in an airport with nothing better to do :-)

You state that Uwingu is a non- profit organization. It is not. It is a for profit company. It says so on its website. This company charges for this whole naming thing and has to make a profit. Proceeds will end up in the pockets of Alan Stern and his investors. Caveat emptor.

Hi, Anon. You are right about it not being a nonprofit, but I think you are wrong that funds are just there to line the "pockets of Alan Stern and his investors". Caveat emptor, indeed, but regardless of Stern's trustworthiness that doesn't make the IAU's statement any less erroneous. There was no due process here, Commission 53 did not authorize that press release, and is not IAU sanctioned.

Uwingu doesn't name planets any more than the IAU names planets. The difference is that the IAU won't take $4.99 from you for the privilege of not naming a planet.

Uwingu's pitch has the potential of causing a lot of confusion and the IAU was presumably called on to respond to that. The fact that the IAU is a slow clumsy body does not change that Uwingu is laying the groundwork for future confusion and disappointment, and getting remarkably little return on investment for it. With all these luminaries involved with it, I really thought they were going to have a better business model.

Benjamin: As long as Uwingu is not committing fraud (which is a reasonable inference of the IAU's press release, see:, I don't really care if they pursue seeking popular names for exoplanets. I agree that they should be even more clear than they already are that their names are not "official," and I said so in my post.

I DO care that the IAU is issuing press releases that dub certain names and lists official without actually consulting the relevant committee. I also find it bizarre that the IAU denounces these popular names (sight unseen!) but not all of the other popular names used by astronomers and the public that violate its official nomenclature (or, in the case of exoplanets, lack thereof). Where were they when astronomers announced "Zarmina's World", "Methuselah", and "Tatoonie" (twice!)?

Ask Stern et al if they will pledge to never take a penny of income from Uwinu. They won't because they are ultimately looking to make lots of money off of this. They want to have it both ways. They want you to buy something from them because they are charitable even though they are not a charity. The IRS will be looking into this soon enough.

Thanks for this relatively thoughtful analysis, most of which I agree with. But there are a couple things that bother me about your analysis:

- I think there is a serious disconnect in this discussion about the meaning of "official", which many are conflating with "legal". "Official" in this context can only mean the following: folks who make atlases and write books need to know what to name things in the sky. Most will want to use the same names as "everyone else" (whatever that means), so when you have a discussion of the same object in different books the same name is used. The simplest and sanest way to get this is to have a single arbiter for names that resolve conflicts etc. (a naming convention is also nice but it's hard for me to imagine a convention that makes sense for thousands of planets). For things in the sky the IAU has filled this role, and it makes sense for them to continue to do so. So the only thing it means, when a name is not "official" in this sense, is that you have no right to be upset if that name does not appear in books and star atlases. I read that this is all the IAU is claiming. Other than that you can call a thing in the sky anything you want.

- While the IAU has not defined lists of planet names, they have approved catalog naming conventions, and these appear on This is all the IAU claims.

- Your statement "Contrary to the press release's assertion, Commission 53 has not foreclosed the possibility of using Uwingu's names" is inconsistent with the IAU press release, which states "... IAU Commission 53 Extrasolar Planets and other IAU members will be consulted on the topic of having popular names for exoplanets ...".

- (more of a nit) The IAU press release went out with Thierry Montmerle as the first contact. Do you really believe this was done by a "rogue press agent" without Montmerle's approval?

Other than that I think your analysis is the best contribution I've seen to this discussion :)

Hi, Steve. Thanks for your input.

1) I agree that the IAU should be our professional arbiter for planet names, and that this is a useful and proper role for it to play. I don't think I asserted, or even really implied, otherwise. The IAU can name the exoplanets. My issue is that the press releases says they have done this already, when in fact they have not.

2) Even if the catalog designations of stars have been approved, the use of those designations to identify exoplanets has not.

3) The IAU press release certainly does assert that the IAU has foreclosed using the names: it asserts that the Uwingu certificates "will not lead to an officially-recognised exoplanet name, despite the price paid or the number of votes accrued". This matter is for the Committee to decide, and it has not done so.

4) I have updated my "rogue press agent" comment to absolve Mr. Christensen and clarify my meaning better. I meant no offense nor did I mean to imply that he acted without authority.

Hi Jason - on your points 1 and 2 I still disagree: the IAU press release only says there is an approved nomenclature or "catalog designations", not specific names. I can only speak with certainty about the Kepler confirmed exoplanet catalog nomenclature Kepler-Xx, which was IAU-approved before flight. I take the IAU press release at its word that the other catalog nomenclatures are similarly approved. These are exoplanet, not star, catalog designations.

On the other hand the KOI-XXXX.XX designation is not (so far as know) IAU-approved. But these are just candidates so maybe nobody cares.

On your point 3 you're right: the IAU press release is not internally inconsistent with regard to being willing to consider Uwingu names. I'd bet that the IAU will eventually say that the first statement should read "should not be expected to lead to an officially-recognised exoplanet name...", and that they mean the second statement that I quoted in my earlier comment. In other words the IAU is saying two inconsistent things, and I'm choosing to believe they meant the second one. You may choose differently.

On point 4: Right on! This is where I think the press release should have been much more clear that nothing is settled until commission 53 approves a policy.

Eek: that should have been "On your point 3 you're right: the IAU press release is not internally consistent with regard to ..." We can't edit comments?

Sorry about the clunky comments software; I'll be moving platforms soon.

Actually, the IAU does not even handle or track planet designations. mu Ara is a good example of a system where priority is disputed and the literature is confused. Which planet is d? Is the final word on this? HD 10180 has no 'b' component because the authors weren't sure if the signal was real or not. Is that consistent with the IAU convention?

The IAU stopped tracking exoplanet names because Jean Scneider was doing a better job than them, but they had never made his list official until this press release, as far as I know.

Hi Jason - your comment opens up an interesting can of worms. I would not want the IAU (or any other body) claiming the authority of maintaining an "approved" list of confirmed exoplanets. I'd assumed that and other archives simply make best efforts to reflect the consensus of the community. For example, the NexSci exoplanet archive uses the simple "if it's appeared in a peer-reviewed publication" criterion for planet confirmation.

From this perspective I interpret the IAU press release as pointing to as an example of good use of nomenclature, not as an "approved" list.

Similarly I'd expect the IAU to stay out of your mu Ara example until a consensus was reached.

It makes sense to have a central arbiter for names. Not so much for astrophysical results such as planet confirmations. Also not so much for astrophysical definitions - that has not gone well. How does that sound to you?

Jason, I appreciate your response, but I _do_ care that Uwingu is pursuing popular names for exoplanets. They have a lot of bigwheels on board and make it look important if not technically official. A disclaimer somewhere on their web site is not going to deter the impression that the names are more meaningful than names that I'll give out from Ben's Planet Name Agency, at only $2.99 - but they aren't.

If Uwingu keeps getting publicity traction, I am dead certain that the cumulative amount of time astronomers spend explaining to people that there isn't really a planet named "Ron Paul" (currently ranked #14) is going to outweigh the research time Uwingu manages to fund. In that sense, it's taking money out of the community's collective pocket.

Hi, Steve. The IAU press release states:

"Upon discovery, exoplanets and other astronomical objects receive unambiguous and official catalogue designations. "

This is false. The IAU imparts no such names on discovered planets. Discoverers usually do, unofficially, and they regularly flout the (unofficial) IAU naming scheme, as in the cases of HD 10180 b and mu Ara d and ET-1 and any number of press-release names.

Actually, I would be fine with Commission 53 weighing in on issues like HD 10180 b and mu Ara d; it would prevent the various exoplanet lists from having to coordinate their naming schemes or, worse (and the case now) disagreeing on them. I would welcome the IAU to play that official role, because I do not expect consensus to be reached in the literature.

As for agreeing on what planets are real and which are not, I agree that these things will remain subjective and not in need of any "official" stamp of approval. If the IAU started making those calls I would disapprove but it would not really change anything ( would just add an "IAU seal of approval" flag).

But to my knowledge there has never been a General Assembly vote to give any exoplanet identifier scheme (whether name or catalog designation) the imprimatur of the IAU.

I agree that the press release probably meant to simply point to as an example of the unofficial designation scheme, but that's not what the text of the press release said and that should be clarified.

The President of IAU Commision 53 Exoplanets has today explained to me that the "position stated in the press release was discussed with the Organizing Committee of Commission 53 in advance" and that "the text written by IAU has been released after consultation and approval of the IAU General Secretary." Nothing "rogue" here whatsoever - surprise - while a more thorough statement from the full Commission 53 on the exoplanet naming issue can be expected later this year. As it said in the press release and elsewhere earlier already.

Daniel, I have (twice now) apologized for implying that Mr. Christensen acted without authorization by using the word "rogue", since that was not my intention.

As I explained (thrice now) my point is that neither the membership of Commission 53 nor the General Assembly has voted to resolve that contains "officially assigned catalogue designations" or that Uwingu's process "will not lead to an officially-recognised exoplanet name."

Or does the Organizing Committee of Commission 53 have the authority to make these decisions unilaterally? If they do I'm happy to stand corrected.

Daniel, I have (twice now) apologized for implying that Mr. Christensen acted without authorization by using the word "rogue", since that was not my intention.

As I explained (thrice now) my point is that neither the membership of Commission 53 nor the General Assembly has voted to resolve that contains "officially assigned catalogue designations" or that Uwingu's process "will not lead to an officially-recognised exoplanet name."

Or does the Organizing Committee of Commission 53 have the authority to make these decisions unilaterally? If they do I'm happy to stand corrected.

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