Talk:Ceres (dwarf planet)/Archive 1

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Physical Characteristics

A more recent study led by Peter Thomas of Cornell University, suggests that Ceres has a differentiated interior: observations coupled with computer models suggest the presence of a rocky core overlain with an icy mantle. This mantle of thickness from 120 to 60 km could contain 200 million cubic kilometers of water, which is more than the amount of fresh water on the Earth[6] [10].

200 Million cubic km of water in Ceres mantle? This has to be an error. This would be a cube some 5.84 million km per side!

Actually only 584 km per side. Deuar 15:12, 25 July 2006 (UTC)

Following [1] (Jan 9, 1998) the density of Ceres is only 1.98 ± 0.03 grams per cubic centimeter. Is this more recent/fiable than the current one?193.171.121.30 19:38, 15 Jul 2004 (UTC)

After trawling through the published stuff and getting advice from Myles Standish, one of the researchers, the page has been revised to the current best estimate of about 4.75×10¹⁰ Solar masses. The uncertainty here is of the order of a couple of percent, mostly due to differences in the assumptions used by people, rather than measurement error which is much smaller. Deuar 11:55, 14 September 2005 (UTC)

---

How is density computed/defined in this context, anyway? It does not seem to equal mass / volume (which would give 1.65 g/cm³)!193.171.121.30 19:38, 15 Jul 2004 (UTC)

How did you get that? Mind you, I get 2.12 g/cm³ using the geometric average diameter of 950 km. Deuar 11:55, 14 September 2005 (UTC)

---

The value for the surface area is obviously wrong. A sphere with diameter 932 km has got about 2,728,860 km² surface area, something that is not a sphere has even a greater surface area. I think we don't need the surface area here, one can calculate it approximately from the diameter. 193.171.121.30 19:38, 15 Jul 2004 (UTC)

You're out by a factor of four - it's pi times radius (not diameter) squared Deuar 15:06, 10 September 2005 (UTC)

---

The diameter I've put in is from the Hubble UV observations, an image from which can be seen in a picture in the article. The accuracy is about ±10km. Presumably when the newer HST data is published better values will be given. An issue related to this is: which diameter to use for surface gravity and escape velocity data? I would suggest the larger, since then we at least know that the entire mass given in our data is within the radius.

And a question for someone in the know - how is the mean surface temperature in the table calculated, or where is it from? It appears to scale between asteroids like the standard model ( proportional to (1-albedo)^1/4/a^1/2 ), but when I try to scale the Ceres temperature to other airless bodies like e.g. the Moon, I get 277K rather than the 250K given there, which suggests that the mean asteroid temperatures shown may be too high by about 15K. Deuar 11:55, 14 September 2005 (UTC)

Minor Planet Template

Before I go off converting the rest of the asteroids, let's make sure I got the template right. This one conserves all the data in the previous table, and adds some fields. The one annoying limitation of templates, it seems, is that an embedded link cannot be aliased; for example, if I were to replace the current {{Minor Planet | orbit=413.949 Gm (2.767 [[AU]]) ... with {{Minor Planet | orbit=413.949 Gm (2.767 [[Astronomical Unit|AU]]) ..., the display breaks at the pipe right after "Unit". Until this Wikibug is fixed, we'll have to live with somewhat lesser-looking links.

I use a Delphi 8 applet I wrote that browses the oft-updated AstOrb.dat (available from http://asteroid.lowell.edu/); it has a button that grabs the data, computes some and spits out the template wiki-code to the clipboard. I only need to fiddle with it and add a few things such as the discovery and alternate designations data (which I get from http://www.hohmanntransfer.com/moc/index.html).

Urhixidur 02:48, 2004 Jul 22 (UTC)

The link for "spectral class" goes to spectral classification, which is all about stars. Before it went to spectral class, which is a disambiguation page.

Probably there should be a separate asteroid spectral class page... and it should be created before changing all the templates.

Also "rotation period" should be "rotation period", and "revolution period" should be "orbital period".

"Category" is unlinked, I wonder if there's some useful link it could point to. Right now the relevant information is on the "Minor planet" page. Maybe a the Minor planet page should be renamed to "Minor planet families" or something, and the new "minor planet" page should be much smaller and should link to "minor planet groups" and various other links.

-- Curps 04:29, 22 Jul 2004 (UTC)

Periods - done. Spectral classification - now links to [[Asteroid#Spectral classification]]. Category - now links to Minor planet (which is nearly all about asteroid categories anyway).

Urhixidur 12:15, 2004 Jul 22 (UTC)

How can the Absolute Magnitude of 1 Ceres be 3.34? That would give it a luminance as strong as some stars. Is this meant to the the Apparent Magnitude from earth? Even so, that seems brighter than I expected for the planetoid. ---- Tesseract501 March 23, 2006.

Asolute magnitude used for stars differ from absolute magnitude used for asteroids - they are two different units of measurement.--Nixer 19:38, 23 March 2006 (UTC)

Thanks Nixor. I see (for planets/oids, they use 1AU -- for stars they use 32.62 l.y.). The same term for both is confusing. Its too bad that the Astronomers use the same term for different formulas (e.g., "Absolute Resonance" for bodies that reflect light more than generate light). But at least the symbols (M vs. H) are different. Thanks for clarifying things for me ----Tesseract501 March 24, 2006.

Adjectival form

Two possibilities crop up: Cerian and Cererian. Anyone know the genitive form in Latin? kwami 06:53, 2005 Jun 19 (UTC)

Actually, the word 'cereal' would suggest Cerean (si-ree'-un).

Okay, it's Cererian, from the Latin Cereris, as preserved in the Russian and Bulgarian Церера. kwami 2005 July 6 07:12 (UTC)

Hi, Badger,

You say that "the simpler Cerian or Cerean are more commonly used." Have you found references that use these forms? That would be worth noting here for future reference. I only find "Cerean bodies" in sci-fi refs. kwami 00:14, 2005 August 21 (UTC)

Oh no, I just found the sci-fi ones too (both forms). That counts as usage though, right? Couldn't find any scientists using anything at all. The Singing Badger 01:36, 21 August 2005 (UTC)

Italian Cerere also preserves the common Latin s~r alternation in the root, so yeah, Cererian. kwami 10:59, 16 November 2005 (UTC)

So why not Cereran? Cererian looks like a double derivative (from Cereria from the root Cerer(i)-).

The true Latin adjective, I suspect, would be Cererin-a/us/um, which would give Cererine in English. —Tamfang 19:03, 20 February 2006 (UTC)

Yes, quite possible. I was thinking of an adjective that could pull double duty as a demonym, as "Jovian" or "Martian". kwami 19:27, 20 February 2006 (UTC)

So? Any Latin adjective can do that, though English-speakers these days may hesitate to use -ese (from L. -ensis by way of Old French) in the singular. —Tamfang 22:27, 20 February 2006 (UTC)

What about Ceresian?—The preceding unsigned comment was added by 131.111.8.98 (talk • contribs) 12:00, 24 August 2006 (UTC)

What about it? We shouldn't include original research or conjectures, this article must include facts which are verifiable from primary external sources. The only sources anyone has found are the Sci-Fi ones noted. Derek Balsam 16:33, 24 August 2006 (UTC)

Ixion

Ixion is listed as being larger than Ceres, however at the Ixion page its stats put it at a smaller 822km. Ixion is removed from the list as being a "larger" object than the 975km Ceres.

Ixion was believed to be larger than Ceres at the time of its discovery. It was later shown to be smaller, because it is much more reflective than originally thought.--Jyril 10:10, 22 October 2005 (UTC)

planetary symbol

It would be nice if someone were able to add the planetary symbols assigned to Ceres, Pallas, Juno, & Vesta before Astraea was discovered. kwami 04:53, 16 November 2005 (UTC)

Hi! There are on my italian wikipedia! I have made them!!! --Dread83 09:49, 16 November 2005 (UTC)

Thanks, Dread. If you make them, I will steal them! kwami 11:46, 16 November 2005 (UTC)

Here's more asteroid signs, unfortunately the images are poor: [2]--Jyril 16:35, 16 November 2005 (UTC)

In italian wiki I've also Astraea, Hebe, Iris, and Eunomia. Ciao! --Dread83 19:33, 16 November 2005 (UTC)

Weren't these just used for astromancy? By this time they'd decided that these weren't planets after all, which is why I stuck to only the first four. I guess we could put everything in if we wanted to, though I don't know where it would end. Also, they don't seem very standardized. kwami 23:18, 16 November 2005 (UTC)

Hi there! There's a good essay on the web regarding these symbols and how they were used in astronomy at [3]. An annoyance is that the symbols they have there (and in the original papers which can be found on ADS: Ceres to Eunomia, 28 Bellona, 35 Leukothea, 37 Fides) are different in their details to what we have in the article presently. I have to say these Italian ones are more elegant and simpler, though. Deuar 11:18, 17 November 2005 (UTC)

Hi! In order to design the first four symbols I have followed the indications of symbol.com symbols.com. --Dread83 08:55, 18 November 2005 (UTC)

I think that's not the right link... kwami

Oh, sorry! ;) --Dread83 12:09, 18 November 2005 (UTC)

Bloody Herschel

Can somebody find & include the term Piazzi used to describe Ceres? Herschel's "asteroid" only gained currency because he was better known; science (& we!) should use the term the discoverer preferred, N? Trekphiler 13:52, 16 December 2005 (UTC)

He called it a planet, although he at first announced it as a comet until he had better data on its orbit. It was Herschel that decided it was too small to be a proper planet, but 'planet' it was called for decades. Almanacs listed 11 planets in the mid 19th century (Neptune had not yet been discovered). kwami 00:22, 17 December 2005 (UTC)

Isn't it currently one of the planetoids who's status will change under planemo v. fusor schema?

Mass reference

I'm reverting to the old main belt mass estimate of 23E20kg. The current figure of 30E20 is based on a reference that appears to be gibberish. Someone please correct if you have better data. kwami 22:54, 18 December 2005 (UTC)

Hmm. Indeed. That link was fine until recently, but it appears to have been changed to give just the abstract. The abstract on ADS now gives the relevant data. I'll fix the references immediately, and lets mull on whether to change the mass estimate back. It seems no less trustworthy than the previous smaller one, I guess. Deuar 12:58, 19 December 2005 (UTC)

If the total mass estimates rely on different masses for the large asteroids, we should use the one that best matches the asteroid masses we're using. Otherwise, I don't know which we should go on. kwami 19:03, 19 December 2005 (UTC)

Hi Kwami. That Pitjeva paper fits data to several independent parameters. Of those, the asteroid parameters fitted are the masses of 1 Ceres, 2 Pallas, 3 Juno, 4 Vesta, 7 Iris, and 324 Bamberga, as well as the heliocentric radius and mass of a model ring of uniformly distributed small masses. To get the total mass of the asteroid belt, they then add up the above fitted masses, along with rough mass estimates for about 300 of the remaining largest asteroids. So that total mass estimate of 3e21 kg is not very sensitive to their calculated masses of Ceres, etc, since the most variable fitted value (the mass of that model ring) is independent of those. Certainly not sensitive enough to account for the 7e20 kg difference between the two estimates we have. What is worrying, though, is how that big difference of 7e20 kg comes about --- Pitjeva gets a mass of 6.6e20 kg and a radius of 3.13 AU for that hypothetical ring in the model. That radius seems a bit too large, and it then seems likely by gut feeling that systematic error is of the order of a few times 1e20 kg (on the too large side). So, um, where does that leave us? After spouting all that text I now tend to think we should leave the old estimate of 2.3e21 kg, since the Pitjeva one is very fresh, in an obscure journal, and probably has not been properly assessed by the astronomers yet. Deuar 20:24, 19 December 2005 (UTC)

Sounds good. kwami 20:28, 19 December 2005 (UTC)

Ceres "has more than half the mass of the rest of the belt put together" — does that mean Ceres is more than 1/3 of the total, or more than half? —Tamfang 18:59, 20 February 2006 (UTC)

Yep, it's still confusing, it seems. Maybe we should just say it straight: 40%. Deuar 09:03, 21 February 2006 (UTC)

Much better! —Tamfang 18:23, 21 February 2006 (UTC)

It is very confusing to me: the different website sources indicate 1 Ceres as 40% the total mass, or 1/3 total mass, or 25% total mass. Does anyone really know? Maybe some calculations consider all the belts (Main, Oort, Apollos, Centaurs, etc)??? While others only consider the Main Belt??? ---- Tesseract501 March 23, 2006.

The main problem is estimating what the total mass of main belt is (Trans-Neptunian objects are excluded). I.e. "no one really knows" ;-) It's accuracy is pretty well reflected by the spread of values you gave. The problems with estimating the mass of the whole belt are 1) You can't see the small bodies below several km diameter, and there's all kinds of guesstimates as to how many of each size there are; 2) Densities are only known to any sensible accuracy (e.g. <20% error) for maybe two dozen asteroids which account for about 1.5 Ceres masses. The rest, well, it's a guessing game again. Some numbers are given in a post just above. I believe the reason we have the 40% value at the moment is that several asteroids are compared to the 2.3e21 kg (whole belt) estimate, so at least it's consistent. Deuar 16:50, 26 March 2006 (UTC)

I have to apologize. I stumbled into this mass controversy at Asteroid without realizing it was being discussed here.

I thought that the Pitjeva approach sounded pretty clever. And, she only attributes 1/3 of the total asteroid mass to the parameterized ring --- 2/3 is in the top 300 asteroids. So, any error in the estimate of the small asteroids wouldn't cause a large error. If you look at the abstract of their Icarus paper ([4]), they claim the double checked their estimate versus fitting to some sort of theoretical distribution (power law?) of mass versus asteroid number, and get the same answer. I haven't read the Icarus paper, but it sounds pretty good to me... Their Icarus paper gives an estimate of 3.6e21 kilograms, even higher than their previous estimate of 3.0e21.

I don't know where NASA got its 23e20 kg number, it would be interesting to find out where that came from.

-- hike395 05:57, 29 March 2006 (UTC)

Well, the more logical place for this discussion is Asteroid i'm sure! I agree that Pitjeva's approach is pretty clever and at least uses a sort of direct measurement of the mass rather than counting up a hypothetical power law. My guess is that the 23e20 estimate comes from some kind of counting, but I'm not sure. It's a bit worrying that her estimates have been creeping up beyond the quoted error, and that the modelled ring is so far out (the main belt appears to be centered more around 2.7AU). Suspiciously Mars ranging would be very important for the calculations, and at Mars you can imagine that [massive asteroid ring further out] = [smaller asteroid ring closer in]. Still, it's probably better than a number from "somewhere". I seem to recall seeing an even smaller estimate of 18e20 kg somewhere as well. Anyway, maybe i'll try to track down that Icarus paper. Deuar 09:09, 29 March 2006 (UTC)

If those are standard deviations and if the underlying true value is 3.2e21, it would be 1 standard deviation below their new estimate (36±4) and 1 above their old (30±2), which seems plausible.

I hear what you're saying about the location of the estimate main belt --- that would indicate there is a visual observation bias for the small asteroids towards the Sunward side of the belt --- the observations all occur near 2.7AU, while the mass is more centered around 3.1AU. This matches their claim that only 10% of the asteroids with H<14 have been discovered.

We can wait until you find the Icarus paper, if you like. --- hike395 14:12, 29 March 2006 (UTC)

Ok - i've found the Icarus paper. Found two actually, which unfortunately increased my confusion. Here's a rundown of the data:

reference	Total mass of Belt	Mass of ring	Radius of ring	comment
Icarus 158, 98 (2002)	3.6±0.4 e21 kg	1.0±0.2 e21 kg	2.80±0.08 AU	submitted 2001
Icarus 158, 98 (2002)	3.3±0.4 e21 kg	0.72±0.2 e21 kg	?	last-minute addition (2002) using fresh ranging data from MGS
Solar System Research 39, 176 (2005)	3.0±0.2 e21 kg	0.67±0.07 e21 kg	3.13±0.05 AU	presumably includes newer ranging and asteroid data

Well, 2.8 AU actually sounds pretty reasonable! The ring location in the newest calculation looks a bit suspicious, though. However, it occurs to me that as more asteroids are discovered (there's been a deluge since 2001 when the first paper was submitted), they tend to preferentially be at small solar distance. The outer main belt is also dominated by dark C-type bodies which further increases this effect. All in all I can now imagine that a majority of the mass in "unseen" objects could be out around 3 AU.

From a plot in the Icarus paper, I'm guessing that the NASA value was obtained just by counting up the asteroids with known radii at the time (whenever that was). Pitjeva already gets about 2.6e21 kg just by counting up the asteroids known in 2001 without even considering the un-observed ones. I would now be more suspicious of that NASA value of 2.3e21. Deuar 21:35, 29 March 2006 (UTC)

Simply counting up the asteroids sounds wrong. Should we just report it as 3.0-3.6 e21, perhaps computing the fractions using the (latest, perhaps more conservative) 3.0 value ? -- hike395 03:04, 30 March 2006 (UTC)

Sounds good! Deuar 10:33, 30 March 2006 (UTC)

Deuar -- do you happen to have the title for the 2005 Solar System Research paper? This article says one thing, but the JPL web copy of the paper [5] says another. Is there a second paper? Thanks! -- hike395 15:19, 30 March 2006 (UTC)

The link you gave goes to the one I recognize - High-Precision Ephemerides of Planets—EPM and Determination of Some Astronomical Constants. What do you mean that the article says something else? Do you mean the apparent difference in page numbers from the Russian version, or have you found another article? Deuar 15:57, 30 March 2006 (UTC)

Several of the references around Wikipedia (including here at 1 Ceres) say the title of the article is Estimations of Masses of the Largest Asteroids and the Main Asteroid Belt From Ranging to Planets, Mars Orbiters And Landers, same author, same journal, same pages, same year. I can't tell if this is a mistaken title, or if there is another paper out there. -- hike395 16:26, 30 March 2006 (UTC)

Later: I see what's going on. That's the title of Pitjeva's 2002 conference paper. We should go through and fix it up. -- hike395 16:34, 30 March 2006 (UTC)

We should. However - we should be careful because the weblink to the abstract is used also as a reference for the masses of the individual asteroids: Ceres and a couple of others where it appears. Deuar 18:16, 30 March 2006 (UTC)

I suppose we must not know the orbits of Jupiter and Earth to sufficient precision to enable us to calculate the mass of the Main Belt from them. Pity. kwami 00:05, 31 March 2006 (UTC)

I think Mars is actually better for this because it's closer to the main belt, on a more eccentric orbit, and smaller (all of which cause that it gets perturbed more strongly). As we get more years of data from spacecraft in Mars orbit the estimates should get better, I hope. Deuar 10:48, 31 March 2006 (UTC)

I wasn't thinking of perturbations, though of course corrections would have to be made for them. But the orbital period of each planet depends on its own mass and the mass inside its orbit, so if you compare two planets, you should be able to calculate the mass between their orbits, which for Jupiter vs. Mars would be the Main Belt. kwami 18:50, 31 March 2006 (UTC)

Sounds like a pretty cunning idea. Maybe, as you say, the periods are not known well enough (or the problem is e.g. with the Jupiter distance) Deuar 17:50, 1 April 2006 (UTC)

After all our discussion I see that the old (and suspicious) asteroid belt mass estimate of 2.3×10²¹ kg is still sitting there and grinning. I'm off to finally replace it with the newer and more likely 3.0×10²¹ value. Deuar 13:22, 23 April 2006 (UTC)

Planet

Needs some expansion on the discovery, and its former status as a planet... The fact that it's visible to the naked eye seems like it only had bad luck not being picked as a classical planet.

From the article: "under exceptional viewing conditions a very sharp-sighted person may be able to see the asteroid with the naked eye". It is much too dim to track over time with the naked eye. Jonathunder 04:45, 27 January 2006 (UTC)

I guess this just opened up again. We should definitely discuss it's revocation and possible imminent readmission into the ranks of the planets... and the other astroids with planetary symbols should also get mentions about their former planethood. 132.205.93.195 21:12, 16 August 2006 (UTC)

Article title: "Ceres" or "1 Ceres"?

I propose changing the article title to "Ceres (asteroid)" instead of "1 Ceres"

I believe "Ceres" is the name under which it is commonly known, rather than "1 Ceres", which to me and I suppose many non-astronomers is somewhat puzzling (I first thought it was a typo). I notice that in Encylcopedia Britannica, it is listed simply under "Ceres", and the two google searches below show that asteroid Ceres is listed as "1 Ceres" in only about 15% of the articles.

• "1 Ceres" asteroid: 35k google hits
• "Ceres" asteroid : 227k hits

Of course, in the lead of the article introduction, both names should be mentioned. Jens Nielsen 09:36, 19 April 2006 (UTC)

Well, this applies to every other asteroid article on Wikipedia, so a lot of work would be involved. 1 Ceres is its official name, which is why it is used as the article title, even though it's normally called Ceres in practice. It might be simpler to just explain the meaning of the '1' in the introductory paragraph. The Singing Badger 18:04, 19 April 2006 (UTC)

Actually, the full official designation is (1) Ceres, but dropping the parentheses is often done for named asteroids. Urhixidur 16:45, 21 April 2006 (UTC)

If we remove the "1" from in front of Ceres' name, then where do we stop? After the "big four" (Ceres, Pallas, Vesta, Hygiea)? after the first ten? hundred? only for asteroids bigger than 100km radius? for all named asteroids? None of these are satisfactory, and most are tedious to implement. With the asteroid number as part of the title it's at least consistent. I think the present solution of having a redirect from Ceres (asteroid) is a good solution, no need for further change. Deuar 12:13, 22 April 2006 (UTC)

Agreed. Let's just keep the name as it is.--Jyril 15:41, 22 April 2006 (UTC)

Yup. —Tamfang 18:39, 22 April 2006 (UTC)

It's not clear from the lead sentence that "1 Ceres" is what most of us commonly just refer to as Ceres. I'll make that clear. Jens Nielsen 11:13, 29 April 2006 (UTC)

Shouldn't it be dropped for all asteroids with planetary symbols? I wonder how screwed up astrology will get after this. 132.205.93.195 21:14, 16 August 2006 (UTC)

page history stranded

Someone left the page history stranded at Ceres (asteroid). They should be merged if possible, otherwise I think this page should be copied there, then deleted here, and then that page should be moved here before much other editing is done. kwami 09:09, 29 April 2006 (UTC)

I've fixed this. To whomever moved the page in the first place, please use the Move function instead of just copying and pasting the cotnents of the page. Jude (talk) 03:20, 17 June 2006 (UTC)

VINDICATION

http://www.spacedaily.com/reports/The_IAU_Draft_Definition_Of_Planets_And_Plutons_999.html Get ready for Planet Ceres!!! Hopquick 05:06, 16 August 2006 (UTC)

It is very interesting, and would require major changes to this article and a number of planet-related templates, but people reading this article should be very clear that this proposed definition is just that, a PROPOSED definition. It has not been approved yet. Ceres is not yet considered a planet, and for now, at least until the 24th, it remains just the largest asteroid. As I mention below, I think it is only prudent to discuss possible changes, and as in the edit I made a few minutes ago, mention that change is in status is possible soon, but we shouldn't make this change yet to the main article. We definitely need to wait until this is approved. Let's not jump the gun... --Volcanopele 05:08, 16 August 2006 (UTC)

Planet Ceres Article

The proposed defintion for a planet currently under consideration by the IAU would mean that Ceres would be reclassified as a planet. While this proposal has not been officially accepted, I think it is only prudent to suggest changes here on the talk page for when and if this definition is accepted. See [6] for more information on this definition. here is my suggested edit for the lead paragraph:

• Ceres (seer'-eez (key), IPA /ˈsiriz/, Latin: Cerēs) is the fifth planet from the sun and is the smallest body categorized as a planet. It was discovered on January 1, 1801, by Giuseppe Piazzi, who named the new world after the Roman Goddess of growing plants. With a diameter of about 950 km, Ceres is the largest and most massive body in the Asteroid Belt; it contains approximately a third of the belt's total mass. Ceres has undergone a number of classification changes. Following its discovery it was considered a new planet, but after a number of other worlds were discovered in the asteroid belt in the 1840s, it was reclassified as an asteroid or "minor planet". In 2006, a new definition for planet upgraded Ceres once again to the status of planet.

Above comment posted by --Volcanopele 05:03, 16 August 2006 (UTC)

I thought this day would never come! Hopquick 05:06, 16 August 2006 (UTC)

Didnt think they would consider Ceres as a planet, but lets see what happends imi2 08:16, 16 August 2006 (UTC)

If it is reclassified, shall it and Charon (moon) take the real names, and the dieties currently in those spots, Charon and Ceres, be renamed to Charon (diety) and Ceres (diety) respectively like the rest of the planets? --Kitch 12:22, 16 August 2006 (UTC)

Not a Pluton, a "Dwarf planet."

If the draft is passed, Ceres will be a planet, not a pluton. The term "Pluton" refers to objects in the Kuiper Belt. "Pluton: A planet orbiting beyond Neptune, taking more than 200 Earth years to circle the Sun. So far, it would include Pluto; Pluto's former moon, Charon; and "Xena" (2003 UB313)."An unofficial term, Dwarf planet, could be used to describe Ceres and refers to any planet smaller than Mercury. [7] Eccentricned 11:17, 16 August 2006 (UTC)...................................

................Size shouldn't matter--only shape: The size definition of planet should be scrapped and the spherical quality (global hydrostatic equilibrium) of any object (that is not a star or black hole) should solely define it as a planet (with the caveat that any fundamentally spherical form altered by massive impact yet still largely intact would still be a planet).....Within this scope there should be classes of planets-- similar to classings of stars-- 1) Dwarf Planets (like Ceres); 2) Classical Planets (terrestrial and gasseous planets in the Pluto to Jupiter range); 3) Super Planets (three times Jupiter in size and larger); 4) Super-Maximum Planets (brown dwarves that exist just below the gravitational threshhold of igniting into stars). --Phil Murray Sean7phil 12:07, 16 August 2006 (UTC)

Actually, Pluto won't be a classical planet anymore:"The IAU draft resolution recognises eight "classical" planets - Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune - three "plutons" - Pluto, Charon and UB313 - and the asteroid Ceres." [8] Also, "Dwarf Planets" is not an official term but is defined as "smaller than mercury"(as seen from the list of new definitions I referenced above). The only official term to be added is "Plutons" which that list doesn't even mention. Where are you quoting the list from, it doesn't resemble any of the articles I've read today? Eccentricned 14:11, 16 August 2006 (UTC)

That is a misreading of the article. Hopquick 14:19, 16 August 2006 (UTC)

Fundamentally, there isn't much difference between Mercury and Ceres. Look above for the links to the articles. Hopquick 14:20, 16 August 2006 (UTC)

It seems to me there's far more commonality between the terrestrial planets and all the other bodies everybody's arguing about; as you say Mercury and Ceres are quite similar, or certainly more similar than Mercury and Jupiter. The "odd guys out" are the gas giants, if anything. I think the only way to make sensible classifications is to consider "planet" as very broad, as with the term "animal". Then we'd have gas planets (several categories thereof, perhaps) and solid ("terrestrial") planets which might then be subcategorised as rocky or icy. There's no really rational way to create a class of objects that includes Jupiter and Mercury but that excludes Pluto or Ceres. It's much like trying to create a special category in biology called "important animals" and then cherry-picking statistics to try to include lions and exclude hyenas or whatnot- "Must wheigh more than x kilos when mature"/"must be one of the top 5 predators in its niche or one of the top 5 herbivores"/and so on. IMHO :) 82.71.30.178 16:11, 26 August 2006 (UTC)

Where's that quote from? super maximum, super, etc? Zzzzzzzzzzz 05:10, 17 August 2006 (UTC)

It's my idea-- (super and super-maximum planets). Although I'm sure it's a conclusion that many could come to (not earth-shatteringly innovative). Sean7phil 17:56, 17 August 2006 (UTC)

I've edited out the reference to Ceres as a Pluton, as it is clear from what the IAU has said that is Not a Pluton, it is a planet by the new definition, and it is called a Dwarf planet informally. --Hibernian 14:37, 17 August 2006 (UTC)

Sentence in intro

Currently there is a sentence in the first paragraph as follows: "Ceres name derives from Roman goddess named Ceres, depending on context." Can anyone explain what this means? Usually a phrase like "depending on context" accompanies at least two choices, not just one. This looks like the result of an incomplete edit, where someone removed some words from the sentence but did not pay close enough attention to what remained. I looked at the section of the article entitled "Name" to try to find out what the two (or more) alternate meanings of "Ceres" (if any) might be, but it is not clear. I notice that the proposed rewrite of the lead (above) would remove this issue. Obviously this article is going to be attracting greater attention in the coming weeks and months as Ceres gets "promoted", so it would be a good idea to clean this up now. 6SJ7 16:33, 16 August 2006 (UTC)

article title

Mmm... there has been some debate over this, but the article still doesn't explain to a lay person like me why the title is 1 Ceres and not just Ceres. That should be covered in this article, and I think even in the lead section.--Steven Fruitsmaak | Talk 16:56, 16 August 2006 (UTC)

Actually, I was about to propose that the title be changed. I'm assuming that the "1" has to do with the asteroid listings. Assuming that the proposal passes, Ceres will no longer be an asteroid, and would, I assume, lose the "1". The page here should then, IMHO, be renamed to reflect it's new status. I would suggest Ceres (planet) as a simple, straightforward new name for the page. This is totally assuming that the proposal passes on the 24th. If it fails, any discussion of renaming the page is totally moot. - TexasAndroid 17:07, 16 August 2006 (UTC)

It certainly won't lose its numbering even if it becomes a planet.--JyriL ^talk 17:57, 16 August 2006 (UTC)

It may not lose it's number, but would it still make sense to refer to it with it's asteroid numbering, when it's been upgraded in classification to a dwarf planet? - TexasAndroid 18:18, 16 August 2006 (UTC)

If and when it is classified as a dwarf planet, I would agree that the article would be changed to Ceres or Ceres (planet). However, we definitely should mention in the naming section (maybe even in the lead paragraph) that this object was previously refered to as 1 Ceres since a lot of print and even internet sources will still be refering to it as such. --Volcanopele 19:39, 16 August 2006 (UTC)

Agreed. No renaming of articles until things are official, in a little over a week. Just trying to get a little ahead of the game, assuming that the proposal passes, and see if a new article name can be agreed upon ahead of time. - TexasAndroid 19:49, 16 August 2006 (UTC)

Well, if Ceres becomes planet, I don't see any reason not to change the article title to Ceres. Mercury is the only obvious example where disambiguation is justified.--JyriL ^talk 23:45, 16 August 2006 (UTC)

I added an explanation of the number in the first paragraph. The Singing Badger 18:08, 16 August 2006 (UTC)

I would have supported removing it from the lead paragraph, but it is certainly a lot better than it was. The previous wording on why there is a 1 (and why there aren't parentheses or some such) was very distracting a derailed the lead paragraph by dealing the unnecessary details that belong more in the Name section. The current wording is far more concise. Thanks The Singing Badger. --Volcanopele 18:15, 16 August 2006 (UTC)

Stop the Insanity!

THIS IS NOT A PLANET.

God damn you Astronomers.

Pluto is not a planet. Charon is not a planet. Ceres is not a planet. "Xena" is not a planet.

Ridiculous!—The preceding unsigned comment was added by 65.26.237.75 (talk • contribs) 20:39, 16 August 2006 (UTC)

oh, but it is. sign your comments. ST47 20:41, 16 August 2006 (UTC)

To remember Ceres and the other planets, this should help: My Very Eager Mission Control Just Showed Us New Planets Named X.

Since when does Charon start with an N? And Charon and Pluto orbit each other.. so do we have a sentence that can have the C and the P be interchangeable depending on the current situation of the two "planets." Psh. Shouldn't the starting point for a "planet" require that the object orbits the sun?? Pluto and Charon are just binary moons. They orbit a nonexistent planet. Insanity I tell you!-65.26.237.75 00:25, 17 August 2006 (CST)

Officialy, there are no Planets. There is no definition of a Planet so no Planet can exist. Do you know that there hasn't been an official definition of a Planet since the one coined by the Ancient Greeks? Of course you didn't, it was something like "A planet is a heavenly light which moves through the Zodiac and isn't a comet." So you can see why it was discontinued. Anything that fits whatever official definition is passed next week, will be a Planet.

"Orbit a nonexistent planet?" What kind of crap is that? Every multiple object system orbits a centre of mass between the two, as is known by anyone who has done High School level physics. In the case of Pluto-Charon, this centre of mass is not beneath the surface of either object, so neither object can be a moon. For an object to be a moon, it must orbit a centre of mass beneath the surface of a Planet. The "Planet" is the one which contains the centre of mass beneath it's surface. This is true for any multiple body orbit, be it planet-star, moon-planet or comet-star. There is a centre of mass which BOTH objects orbit, not a central object which sits there while the other whizzes past. If they are orbiting another body, then it's the Centre of Mass, not the planet, that orbits the larger body. If you were to measure the motion of the centre of the earth around the Sun and the motion of the centre of mass of the Earth-Moon system, the latter will give a perfect ellipse while the former would be a wobbly line about that ellipse (one of it's focal points being the centre of mass of the Sun-Earth+Moon system as opposed to the centre of the sun). EVERY moon-planet system is basically two objects which orbit each other.

This short lesson in basic Physics and the History of Astronomy was brought to you by Eccentricned 14:53, 17 August 2006 (UTC)

Face it, the term 'planet' (in terms of our own solar system) has become partly cultural. There was an uproar in the non-scientific community when Pluto was first anncounced as possibly being declassed.

But I think a case can be made that spherical or spheroid substellar bodies count as planets (although very small ones would be 'dwarf planets'). Basically round sub-stellar bodies could reasonably be called 'planets' even by scientific standards, and then differentiations (dwarf, pluton, classical, and some kind of 'super planet' designation for very large planets [and 'super-maximum' perhaps for close-to-star-threshhold brown dwarves] could cover the rest). This is not scientifically unreasonable and also satisfies public emotions about the issue. Sean7phil 18:08, 17 August 2006 (UTC)

Ok stop arguing. If I'm correct on other talk pages of controversial topics they say not to debate it one wikipedia talk pages.--Scott3 23:21, 17 August 2006 (UTC)

The definition should be simple. The object has to revolve around the sun, it has to be spherical, and it has to be large enough for people to create a civilian colony on the surface. Malamockq 14:30, 18 August 2006 (UTC)

Ceres or 1 Ceres?

What's with the 1 and is it part of its name?--Sonjaaa 22:59, 16 August 2006 (UTC)

All asteroids are given a number as well as a name, and the formal title for the asteroid uses both. See Asteroid#Naming asteroids. Bryan 23:17, 16 August 2006 (UTC)

So when/if it gets promoted to planet again, it will drop the 1 ?--Sonjaaa 00:06, 17 August 2006 (UTC)

I have no idea. 2006 redefinition of planet may have some information about it in its references, but I wouldn't be surprised if the matter simply hasn't been decided yet. Bryan 01:07, 17 August 2006 (UTC)

• You can already name it just "Ceres", numbering is just to help, as there are numerous asteroids, so if it is classified as a planet, it will become Planet Sol V. Earth is Sol III.--Pedro 14:47, 17 August 2006 (UTC)

Amalthea (moon) was formerly called Jupiter V, according to order of disovery, though it's lower than any of the Big Four. —Tamfang 02:04, 19 August 2006 (UTC)

Name

I guess if they add three new worlds to our list of planets, we will be able to officially refer to them as the World Charon, the World UB 313 - and the "World Ceres." Roger 01:58, 17 August 2006 (UTC)

the symbol thingy

Why are there 4 symbols? Can we have a paragraph or section that explains which on is the most often used or most official?--Sonjaaa 16:01, 17 August 2006 (UTC)

None of planet signs are "official". In the case of Ceres, the sign (every version) fall out of use after it was no longer considered as a planet.--JyriL ^talk 17:55, 17 August 2006 (UTC)

Images

Could we promote the model of Ceres Image:1 ceres hst 2005.jpg from halfway down the page to the infobox, and demote Image:Ceres Hubble sing.jpg from the infobox to halfway down the page? Other articles on heavenly bodies (see Mars, for example) use composite images in their infoboxes. --M@rēino 16:37, 17 August 2006 (UTC)

Certainly not. The current infobox image is the best "real" image of the object that exist (I don't know if there's better images by the Keck telescopes, but in any case they wouldn't be in public domain). The model is a sphere mapped with a crude Ceres map and is not a bit more informative. The model also gives unrealistically "clean" view of the object. In reality, it is most likely more rugged (c.f. Saturn's icy satellites like Tethys, which is slightly larger than Ceres). We have to wait several years until Dawn gets there and gets better images.--JyriL ^talk 18:02, 17 August 2006 (UTC)

• I agree with Jyril.--Pedro 00:20, 18 August 2006 (UTC)

Shape

In the article, Ceres is described as a spheroid with dimensions 975 * 909 km, and also as oblong. I suppose this means the axes are 975 km, 909 km and 909 km, making the volume 4.22*10^17 km^3 and the density 2.25 g/cm^3 using the mass 9.5*10^20 kg. Or are the axes 975, 975 and 909, making the volume 4.52 and the density 2.10, in better agreement with the value 2.08 given in the article, but making the spheroid flat rather than oblong (if I, a non-native speaker, understand these words correctly)? I have NOT checked the references, but does anyone know, or can you explain the discrepancy between my calculated density, 2.25, and the given one, 2.08?--Niels Ø 12:40, 18 August 2006 (UTC)

When you say oblong, are you referring to while lightcurve analysis of 10 Hygiea indicates it is oblong? That means 10 Hygiea is oblong, not Ceres. Henry^Flower 14:31, 18 August 2006 (UTC)

Errh - hum - yes, I do. Sorry. Also, the flat shape seems more probable to me due to centrifugal forces. But I think the article (as well as a table in Definition of planet) could be clearer here - could one e.g. write 975²×909 km instead of 975×909 km, or would that confuse more than it helps?--Niels Ø 15:48, 18 August 2006 (UTC)

Pictures

Dumb question, If Ceres is so near Earth why are the pictures so poor? LCpl 21:20, 18 August 2006 (UTC)

Because it's small. And because no spacecraft have visited it. The Singing Badger 21:56, 18 August 2006 (UTC)

Just in case this does become a planet

I have a user subpage that is identical to this article but I'm using it to change the article for saying that it's an astroid to a planet. So when the IAU does decide that it's a planet it can be quickly updated. So please make changes to it.--Scott3 20:41, 20 August 2006 (UTC)

• If it is declared a planet, you need more than that, that article you made is for an asteroid not a planet. When they do it, there are many editors that will change that fast, believe me. I'll work on the Portuguese language version though. So the best is to search more info on Ceres, there isn't enough.--Pedro 22:11, 20 August 2006 (UTC)

Yes it is just beginning I'm still working on it--Scott3 (talk • contribs • count) 00:13, 21 August 2006 (UTC)

• Nonetheless I think we should first work on physical features of Ceres rather than the word "planet".-Pedro 11:05, 21 August 2006 (UTC)

Pronunciation

The article lists "siːriz" as the pronunciation of "Ceres", however, I don't think this is even close to the actual pronunciation. The article has "Cerēs" listed as the Latin, and this is the only way I have ever heard the name pronounced, therefore, I think the IPA should be changed to sɛəriːz. --Veratien 22:05, 21 August 2006 (UTC)

siːriz (roughly "SEE-reez" in English, like "series") is the correct pronunciation. The stress is on the first syllable, and both vowels are IPA "i". The Latin "Cerēs" is also correct; the macron on the second ē indicates vowel length, not stress. Derek Balsam 15:01, 22 August 2006 (UTC)

Either way, I've never heard a pronunciation similar to series (sɪəriːz), only "sehriez" (sɛriːz), which is Cerēs, no? Incidentally, I made a slight mistake above; should have put sɛr instead of sɛər. --Veratien 18:23, 22 August 2006 (UTC)

The derived terms from Cerēs in Modern English, in particular cereal and Cerium, show the iː pronunciation, from the Modern English reflex of classical Latin short e due to the Great Vowel Shift. Derek Balsam 18:57, 22 August 2006 (UTC)

Uhm, sorry... Great Vowel Shift? I thought the Latin vowels were ah, air, or, ee, and oo respectively? :/ --Veratien 22:03, 22 August 2006 (UTC)

Yes, the Latin simple vowels were a, e, i, o, u, (and y in inherited words) in long and short quantities. But that has nothing to do with how this article's subject is pronounced, other than as a historical note. This entry is in the English Wikipedia, not the Latin Wikipedia. English underwent a Great Vowel Shift which changed many of the vowels inherited from earlier languages. The word for the asteroid is English, not Latin, anymore. By the way, the Romans pronounced it "kereːs", anyway Derek Balsam 23:40, 22 August 2006 (UTC)

Out of interest, where abouts are you from? I live in London, and have only ever heard sehriez and serez as pronunciations of this name. --Veratien 18:36, 23 August 2006 (UTC)

I'm in the US, but this does not appear to be a case of differing US-UK pronunciation. Random House, Merriam-Webster and Britannica Online all give the only pronunciation as "SEE-reez". I agree, if you can produce a citation for a pronunciation of "SEH-reez", then by all means add it to the article as an alternate pronunciation. But your original claim above that "siːriz" was not "even close to the actual pronunciation" is simply wrong, as evidenced by the dictionaries. At the very least "siːriz" is a correct pronunciation and must remain. By the way, I don't disagree that you may have heard people pronouncing it as you say.Derek Balsam 19:16, 23 August 2006 (UTC)

A Google search for ceres and "SAIR-eez" comes up with nine results, including one from sierracollege.edu, however they all have "DYE-moss" for "Deimos", which I know is incorrect. I've been speaking to some of my mythology-crazed friends, and they have all come up with either sɛriːz or sɛrɛz, but I can't find either on the internet. SEE-reez seems to be the most common. --Veratien 00:17, 24 August 2006 (UTC)

It's extremely common for people to use Latinate pronunciations for astronomical names, such as /sɛriz/, which is why I added the original Latin or Greek whenever I could, despite complaints that this was unnecessary. However, literary English pronunciations are also very common, and are the ones which requires a pronunciation key. I believe I verified the /siːriz/ pronunciation with the OED, but it may take me a couple days to get back to you on that. As for adding the individual Latinate pronunciations, that would mean several additional variants for each moon and asteroid, which would be a real chore. Better instead I think to just follow the Latin or Greek if you wish to go that route, which I have some sympathy for. kwami 19:48, 23 August 2006 (UTC)

I can't find it in OED 2nd Ed., and I can't find the online version. I cede on this one, then. Must make sure I get the proof first before making a fool of myself. ;) --Veratien 00:17, 24 August 2006 (UTC)

Not in the OED, in any version. My bad. I must've used Usonian dictionaries for this one. But in any case, both fully Anglicised and semi-Latinate pronunciations are quite common for astronomical bodies, and none of the variants are official. Not even the Galileian satelites have stable pronunciations among astronomers: Io is commonly found as both eye'-oh and ee'-oh, for example. kwami 14:33, 26 August 2006 (UTC)

A fully Latinized pronunciation would be more like /kɛres/. Obviously, nobody pronounces it like that now. So just follow the anglicized way. 72.49.88.55 15:00, 24 August 2006 (UTC)

Not A Planet

Is the official interpretation of the IAU vote that "Dwarf Planet" = "Not A Planet", ergo "Ceres" = "Not A Planet"? Hopquick 14:41, 24 August 2006 (UTC) References (e.g. CNN) are saying Ceres will definitely be a Dwarf Planet -where does it say that its status is still uncertain?Surfermoon 14:45, 24 August 2006 (UTC)

Also, is it correct to say that as a dwarf planet, Ceres is no longer an asteroid? The IAU resolution language says only that the "small solar system body" category includes "most of the Solar System asteroids," implying that there could be asteroids in other categories such as dwarf planet. I don't think the definitions are locked down enough to say for sure that a dwarf planet isn't an asteroid. -- CLB

Sorry, not listed in the OED. My bad.

The clear implication of the IAU resolution is that Ceres is still an asteroid. It's just not a 'minor' asteroid. As presumably Pluto is still a KBO. kwami 17:52, 24 August 2006 (UTC)

• I don't read it like that, dwarf planet will be an official category, and for now there are three dwarfs and 12 candidates. Now there are 3 things: planets, Dwarf planets and Small Bodies of the S.S.--Pedro 19:03, 24 August 2006 (UTC)

Yep. There's also "traditional" categories, like comets and TNOs and asteroids. "Asteroids" now encompasses a lot of SSSBs and one dwarf planet; TNOs encompasses two dwarf planets and a lot of SSSBs. The term "asteroid" hasn't ceased to exist, it just no longer is a definition used by the IAU Shimgray | talk | 10:16, 25 August 2006 (UTC)

The following discussion is an archived debate of the proposal. Please do not modify it. Subsequent comments should be made in a new section on the talk page. No further edits should be made to this section.

The result of the debate was no move. -- tariqabjotu 00:36, 31 August 2006 (UTC)

Rename to Ceres (dwarf planet)

Should this page be renamed [[Ceres (dwarf planet}]]? 132.205.93.19 03:57, 25 August 2006 (UTC)

Votes

For: 2

• --TheFEARgod 12:38, 25 August 2006 (UTC)
• Number has never been part of its name. Ceres is now a Dwarf Planet in the asteroid belt, no longer an asteroid (small body in the Solar System). Dispite this article(dwarf planet), which needs proper POV/original reasearch tag. There is a huge bias in WIKI:EN. -Pedro 13:29, 25 August 2006 (UTC)

Per the Minor Planet Center [9] as of today, this body has the following names: (1) Ceres, A899 OF, and 1943 XB. The number is a valid part of its designation.Derek Balsam 13:40, 25 August 2006 (UTC)

Yes, it can be, but you can also not add it, that is why there is the parentisis. Besides there are no Minor Planets - that doesnt exist any longer.--Pedro 13:52, 25 August 2006 (UTC)

You're jumping the gun by saying that "Minor Planets" do not exist any more. The Minor Planet Center has not changed its name. Be patient.Derek Balsam 13:56, 25 August 2006 (UTC)

Yes, nothing changes that fast :P--Pedro 13:59, 25 August 2006 (UTC)

Ceres' status has been updated, and the number and name designation (1 Ceres) counts only for asteroids.--TheFEARgod 16:18, 25 August 2006 (UTC)

---

Against: 10

• Davodd 07:42, 25 August 2006 (UTC)
• --Niels Ø 08:11, 25 August 2006 (UTC)
• Merovingian - Talk 09:23, 25 August 2006 (UTC)
• There is absolutely no evidence that "1 Ceres" will cease to be used as a name; there is no reason we need to further disambiguate on Wikipedia. Entirely pointless move Shimgray | talk | 10:14, 25 August 2006 (UTC)
• as per previous post Deuar 13:21, 25 August 2006 (UTC)
• Against. Document the names of tthings as they are, not as you theorize they should or might be.Derek Balsam 13:25, 25 August 2006 (UTC)
• Based on the number of postings here, my vote was not counted.Michaelbusch 16:31, 25 August 2006 (UTC)
• Against unless IAU renames it as plain Ceres. --Exodio 14:55, 26 August 2006 (UTC)
• Against. Ceres is still 1 Ceres. Dwarf planet naming has not yet been established.--JyriL ^talk 15:23, 26 August 2006 (UTC)
  • what that has to do with Ceres being in Ceres (dwarf planet)?!--Pedro 22:38, 26 August 2006 (UTC)

• Until the IAU has figured out how to name dwarf planets, Ceres remains "1 Ceres", with the minor planet number.--JyriL ^talk 22:46, 26 August 2006 (UTC)

• Oppose for consistency. FairHair

Discussion

Ceres will continue to be listed as 1 Ceres in the IAU database. I therefore vote against. Ceres (dwarf planet) may be redirected.Michaelbusch 04:01, 25 August 2006 (UTC)

Just a thought: The use of a parentheses in wikipedia article titles is not consistent, nor should it be. As a rule, I think those parentheses should be avoided, except where they are needed for disambiguation. Is that the case here? Well, Ceres is a Roman goddess, but if "1 Ceres" is and remains standard notation, I think we could keep that title.--Niels Ø 08:11, 25 August 2006 (UTC)

Is the "1" really part of the name? My understanding is that it is just a sequence number. If it didn't have a proper name but just an alphanumeric designation then the "1" would be part of the name. How is it referred to in peer-reviewed journals? --Polaron | Talk 23:54, 28 August 2006 (UTC)

The above discussion is preserved as an archive of the debate. Please do not modify it. Subsequent comments should be made in a new section on this talk page. No further edits should be made to this section.

Removal of proposed move

Based on four days of discussion here, I conclude that this article will not be moved for the moment. If the IAU decides that being a dwarf planet removes Ceres from the list of asteroids, that is the time for the proposed move to take place. Michaelbusch 02:06, 28 August 2006 (UTC)

GA Failed

The article fails GA criteria because it is not stable. Obviously that can't be helped as circumstances have changed greatly in recent days and it is a current event, but it means it can't be a GA for the moment. Additionally there are a couple of in the article. Alexj2002 17:28, 25 August 2006 (UTC)

WOO. We did it!

We did it, Planet Earth! No more Pluto! No Ceres! No new planets! EIGHT Planets!

...WE DID IT! WOO. --Trajan, 18:50, 25 August 2006 (UTC)

How mean of you! But let's keep this article about describing me and not our feelings about my planethood. I know what I am, and just because you think less of me doesn't mean I'm not a planet. I am just descriminated against because I am girth challenged. They call me a dwarf! Is Michael Moore more human than Nicole Richie just because of his ability to be larger? So now let's just keep this talk page about me and my current IAU status, please. It's so depressing for me otherwise. --Ceres

For the last time, asteroids still exist, and Ceres is still an asteroid

This is getting ridiculous. Some people are failing to comprehend both what the IAU said as well as common sense. Wikipedia is not a soabox. The IAU said in the final resolution:

All other objects³ except satellites orbiting the Sun shall be referred to collectively as "Small Solar-System Bodies".

³These currently include most of the Solar System asteroids, most Trans-Neptunian Objects (TNOs), comets, and other small bodies.

1. The IAU uses the term asteroid in the definition of SSSBs. This indicates they believe it is a valid term. Unless you'd like to argue that comets and TNO's also no longer exist, then asteroids must still be considered a valid term.
2. The IAU says that most asteroids are SSSB's. This logically entails that some asteroids are NOT SSSB's. Since we know no asteroids are planets, this means some asteroids must be dwarf planets...in fact, the IAU specifically named one asteroid (Ceres) as being a dwarf planet!
3. Asteroid is an informal term of long use. The IAU did not define "asteroid". They defined "planet".

The constant edits removing the term asteroid from the article are contrary to both the fact of the resolution, as well as to the common usage, which must be respected. Derek Balsam 22:59, 26 August 2006 (UTC)

Last time? I love to see such optimism. :P —Tamfang 08:56, 27 August 2006 (UTC)

Not true. The IAU defined Dwarf planets. --Pedro 10:37, 27 August 2006 (UTC)

(2) A "dwarf planet" is a celestial body that: (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape [2], (c) has not cleared the neighbourhood around its orbit, and (d) is not a satellite.

Ceres is spherical. It does not orbit a planet. It has not cleared its neighborhood. The IAU has not officially named it a Dwarf Planet as far as I know, but it really is about a definition. Ceres meets it. --Exodio 12:19, 27 August 2006 (UTC)

Yes, the IAU officially listed Ceres as a dwarf planet. See http://www.iau2006.org/mirror/www.iau.org/iau0603/index.html. Derek Balsam 19:02, 27 August 2006 (UTC)

So Ceres is a dwarf planet. Why can't it also be an asteroid? Earth is both a planet and a terrestrial planet, Jupiter is both a planet and a gas giant, and so forth. Objects can fit into multiple overlapping classifications. Bryan 18:13, 27 August 2006 (UTC)

I have no problem with that. Call it an asteroid if there are other major sources that do. Tha IAU says most of the asteroids are SSSBs, but that means some asteroids are in a different category than SSSB. But it's not a Small Solar System Body by definition. --Exodio 18:53, 27 August 2006 (UTC)

• Ceres is a Dwarf planet in the asteroid belt, like Pluto is a Dwarf planet in the Kuiper Belt. "Planet" because it meets most criteria for planets, but Dwarf because it didn't clean its neighbourhood, the asteroid belt. So a Dwarf planet in the asteroid belt already describes what Ceres is about and where it is located for every audiences, we should be careful with the "asteroid". Most "asteroid" references in this text should be changed to "dwarf planet", except when asteroid is meaningful. Asteroids still exist, no one doubts that. Ceres is a special case. BTW, recent studies suggest Ceres is planet-like not asteroid-like. That's why the original draft proposed it as a full planet, see [10] Thus, saying it is anasteroid is not meaningful in most cases... in the public's mind as asteroid is something like Ida or Eros, and Ceres is not like them. --Pedro 22:12, 27 August 2006 (UTC)

Pedro, agora você é teimoso, mas admiro a sua tenacidade. Sou teimoso também. :) "in the public's mind as asteroid is something like Ida or Eros, and Ceres is not like them"? I believe that in the public's mind Ceres is the very prototype of asteroids, and quite possibly the only one they can name. The public mind certainly did not change with the IAU decision. Let's be patient, since there is such a large body of work calling Ceres an asteroid which did not go away last week, and see if the IAU says anything further which may clarify. Derek Balsam 23:02, 27 August 2006 (UTC)

• Então, vamos aguardar.--Pedro 00:24, 28 August 2006 (UTC)

alternate designations

By the way, a quick search turned up nothing to show why the alternate designations "A899 OF" and "1943 XB" exist and what they mean. Is the first a catalog number? Is the second a relic of a "new" discovery that was officially acknowledged and later recognized as an error? —Tamfang 09:02, 27 August 2006 (UTC)

The alternate designations refer to the time when the modern catalog was set up. All known objects were given new designations while the process worked itself out. At the present time, the literature refers to all objects by {Number} {Provisional designation/Name}: 4 Vesta, 1 Ceres, 433 Eros, 99942 Apophis, 29075 (1950 DA). For very well-known asteroids, the number is sometimes dropped. Michaelbusch 00:01, 29 August 2006 (UTC)

no longer current

I am removing the current event tag since...alas...it is all over. :( Now it's just getting more encyclopedic with what we've got. Hopquick 15:00, 28 August 2006 (UTC)

Can someone archive all the IAU/Planet Ceres discussion? It's pretty much over.

Hopquick 30 August 2006