Stay tuned for an announcement ...
 

The International Astronomical Union will hold its 26th General Assembly in Prague, Czech Republic, August 14-25. See [URL="http://www.astronomy2006.com/"]http://www.astronomy2006.com/[/URL] for details.

Note (on [URL="http://www.astronomy2006.com/science-business-meetings.php"]http://www.astronomy2006.com/science-business-meetings.php[/URL]) that the Committee on Small Bodies Nomenclature (CSBN) and the Working Group Planetary System Nomenclature (WGSN) both meet on August 23. The WGSN morning meeting would be a likely forum for announcing an official ruling on the definition of "planet". That day's lunch would then be convenient for attendees' speculation about revelation, during the early afternoon CSBN meeting, of a permanent name for the object currently designated 2003 UB313.

8 planets?
 

I believe pluto is , as the 'borderline' defining case has after a wasted 70 years, been eliminated. Sound like a case of eat cake and don't dot any
local 'I's.
I would like to see a full report on the influence of pluto in the solar system
in the past 300 years, including whether its center of gravity with the sun lies
outside the sun, before giving the astro first , the benefit of our planets
acceptance.
If they haven't answered whether pluto is in fact a 'border' defining body,
or not , they are negligent.
Certainly, we have all known, that it was not part of the solar dynamo, all
along. But not a planet of the sun?
Was its summer unfelt on earth?
Of course when things get too big , the little guys are eliminated.This time
its a planet.Hogwash.

[quote=David John Hill Jr;85706]after a wasted 70 years,[/quote]In what respect do you think the time has been "wasted"?

Astronomers have acquired a great amount of knowledge about planets since Pluto's discovery, and now have a much more thorough understanding of the range of planetary properties than they did in 1930. For certain technical reasons, it became neccessary for the IAU to create a formal definition of "planet" for use in certain astronomical contexts where the traditional informal definition did not suffice, and they have now done so.

There are other examples in science in which technical definitions of certain terms have had to be created because the common informal definitions became inadequate for particular contexts, and we're getting along just fine with those distinctions.

[quote]I would like to see a full report on the influence of pluto in the solar system in the past 300 years, including whether its center of gravity with the sun lies outside the sun,[/quote]The Sun-Pluto barycenter is always within the Sun.

IIRC, all other Sun-planet barycenters except Sun-Jupiter also are always within the sun.

[quote]If they haven't answered whether pluto is in fact a 'border' defining body, or not , they are negligent.[/quote]Why do you think that omission implies negligence -- within professional astronomy, that is?

[quote]But not a planet of the sun?[/quote]Well, you're free to continue calling Pluto a "planet" without qualification, if you so wish. You'll encounter no real trouble doing so except within certain IAU committee proceedings. Have you ever attended an IAU convention or committee meeting?

[quote]Was its summer unfelt on earth?[/quote]Basically, yes, it was unfelt.

[QUOTE=cheesehead;85769]In what respect do you think the time has been "wasted"?

Astronomers have acquired a great amount of knowledge about planets since Pluto's discovery, and now have a much more thorough understanding of the range of planetary properties than they did in 1930. For certain technical reasons, it became neccessary for the IAU to create a formal definition of "planet" for use in certain astronomical contexts where the traditional informal definition did not suffice, and they have now done so.[/QUOTE]
Ceres was called a planet for ~50 years.

From: [URL="http://en.wikipedia.org/wiki/1_Ceres#Status"]http://en.wikipedia.org/wiki/1_Ceres#Status[/URL]
Ceres was assigned a planetary symbol, and remained listed as a planet in astronomy books and tables (along with 2 Pallas, 3 Juno and 4 Vesta) for about half a century until further asteroids were discovered. Ceres turned out to be disappointingly small for a planet, showing no discernible disc, so Sir William Herschel coined the term "asteroid" ("star-like") to describe it.

This was reasonable. Cylde Tombaugh's widow stated that, although he was sure at the time that Pluto was a planet, that he would be fine with the current decison.

One thing that I have noticed regarding the news articles is that although lots of attention was paid to the fact that Pluto is no longer officially considered a planet, there is little to no reporting about the new definition of a planet, which in my opinion is far more important news scientifically.

The negligent inference....
 

I agree that on macro systems pluto would be too small.Hence in an attempt
to align with searching the universe (other than our local solar system)
calling pluto sized objects, planets ,is ludicrous.
I might say , that the re-definition for Pluto inter alia discoveries IS
important . Perhaps they could waite for more detail ---it looks like for
the moment that the 'moon' of pluto is twice a planet, of at times-our sun,
and pluto. I would like to read the detail on this aspect.When the
Nasa probe gets there in 2015, a better idea might be forthcoming, whatever
a defined object it will be examining.
Wasted? Take heart, by definition, the pope once threw away 10 days to get from Julian to Gregorian.
Funny it was in 1976 I first noticed a deep shadow in the skies, followed a few years by whiteness that was cloudless.
Yellow or white skies without much blue,and in fact green has only now begun to get back to previous standards on most occassions.
Putting pollution the main culprit aside, as the main component,
I might ask where Pluto was and in what season?
When did it pass to this side (from sun) of Neptune, and pass back.
I believe 1999 was approximately the end of its full blown summer-29=1970.
This is a soap box and if I were at the meetings too, I would be sparcely
talking here. Signed H I (ll)

Parallel discussion on this:

[url=http://www.mersenneforum.org/showthread.php?p=86061]http://www.mersenneforum.org/showthread.php?p=86061[/url]

I think it is perfectly reasonable from a scientific standpoint to consider Pluto and all the other eccentric-orbited frozen slushballs beyond Neptune as a different category than "main sequence" planets. On the other hand, I think the IAU's latest set of official criteria for planethood, while better than the first proposal, is still deeply flawed.

Special to pluto
 

What I found interesting about pluto was the 1/2 size of charon.
This made me think it was right on the button of a 4 space definition' as
a single element defined.
In some way, this might show how the geometry,including distance increments defined, volume vs surfaces with density as appropriate, all then compared to the dynamic system(as we already define the forces).
The paint I have under hobbies vaguelly sets up some of the notions.
It is the outermost object and only one, that enjoins this with 2 to 3 dimensional aspect of the whole solar system, I find intriguing. ??????

This object has now been assigned an official name:

[url]http://www.space.com/scienceastronomy/060914_eris_named.html[/url]

[QUOTE=jinydu;87167]This object has now been assigned an official name:

[url]http://www.space.com/scienceastronomy/060914_eris_named.html[/url][/QUOTE]

Too bad Brown seems to like the official name - I was contemplating an anagrammatic headline along the lines of "Naming of 'Eris' causes sire's ire to rise."

When I first heard about the official name on last night's news I though they meant [url=http://en.wikipedia.org/wiki/Ares]Ares[/url], the ancient Greek god of war. That would've been a nice compromise, since Ares (as played by the late [url=http://imdb.com/name/nm0808963/]Kevin Smith[/url]) was a recurring character on the [url=http://imdb.com/title/tt0112230/]"Xena" TV series[/url].

[quote=ewmayer;87182]Too bad Brown seems to like the official name[/quote]He proposed it!

[quote]When I first heard about the official name on last night's news I though they meant [URL="http://en.wikipedia.org/wiki/Ares"]Ares[/URL], the ancient Greek god of war. That would've been a nice compromise, since Ares (as played by the late [URL="http://imdb.com/name/nm0808963/"]Kevin Smith[/URL]) was a recurring character on the [URL="http://imdb.com/title/tt0112230/"]"Xena" TV series[/URL].[/quote]But there's [I]an even better tie-in[/I] that was missed by the author of the AP article quoted on space.com:

As explained on SkyTonight.com's article "All Hail Eris and Dysnomia" at [URL]http://skytonight.com/news/home/3916126.html[/URL],
[quote=skytonight.com]The satellite, now called Dysnomia, is named for Eris's daughter, the goddess of lawlessness — a tribute, says Brown, to the actress who played Xena, Warrior Princess: Lucy Lawless.[/quote]
Furthermore, adding to the perfection of Brown's choice, [quote]the moon also follows another tradition for "dwarf planet" satellite names: Pluto's moon Charon was discovered in 1978 by James W. Christy, and the first syllable in Charon matches the first syllable in Christy's wife's name, Charlene. Brown's wife's name is Diane. "We're going to call the moon Di," says Brown.[/quote]