Who decides Pluto’s future?

The International Astronomical Union (IAU) has decided, at its 2006 AGM in Prague, Czech Republic, that from now on there are only 8 planets. They have decreed that Pluto, along with an unknown number of distant, massive bodies will be known as Dwarf Planets. The BBC report that the IAU expects text books to be re-written, and for schools to start teaching that there 8 planets, just as people who were educated before 1930 (the year Pluto was discovered) were taught.

However, the IAU may find that the public, in true Web 2.0 fashion, are not willing to have this top-down edict imposed upon them. The IAU is a largely self-perpetuating body, comprising 8,796 individual members plus 62 countries who have national members (by contrast the United Nations has 192 countries represented and no individual members). The individual members are hardly the most typical representatives of the world’s view, they are mostly PhDs, 87% of them are male, they are drawn from just 85 countries, and in order to vote they had to be one of the 2,500 who were funded to travel to Prague for the AGM.

What happens if the rest of the world rejects or ignores the IAU’s decision? Do they have any sanctions? The IAU is recognised by Governments as the body responsible for things like naming planets, but Governments are also susceptible to public pressure.

Listening to the astronomers speaking about their decision, such as Professor Iwan Williams, chair of the IAU panel working on the definition of planets, quoted by the BBC, one is struck by the confident way they assert that what they have decided is right in some ‘abstract’ sense. Like some quantitative market researchers, they seem to believe that all problems can be reduced to a set of logical and consistent rules, and that rules need to be consistent, as if there were some theoretically ‘correct’ anser . However in the real world this is usually not so.

We can all agree that light comes in three colours (Red, Green, Blue), that absolute 0 is about -273 centigrade, and that the probability of throwing a 6 with a fair die is one-sixth. However, politicians, scientists, and market researchers often behave in too dogmatic a way when talking about their observations of the real world. Is Scotland a country or a state of the UK? Is a whale a suitable animal to hunt and eat, indeed is any animal suitable? What exactly constitutes a continent, why are Asia and Europe considered to be two separate continents, is Australia an island or a continent? Is that new user segmentation rarely useful?

There has been growing concern about the declining influence of reason and the growth of what Francis Wheen has termed Mumbo Jumbo. Several reasons for this have been put forward such as:

• Science mistakes such as the UK Government’s scientists saying cows could not contract the disease that we now call Mad Cow Disease and saying eating beef was safe (over 150 have since died).
• Scandals such as Hwang Woo-Suk, the South Korean cloning expert who was shown to have fabricated his results.
• Science for hire, such as all those scientists who worked for the cigarette companies in the 60s, trying to show smoking was safe.
• The ‘dumbing down’ of our media and of the wider society.

But surely 2,500 professional astronomers, mostly male, drawn from the richer countries, voting by waving yellow cards in the air, without any attempt to carry the wider public with them, is the sort of behaviour that will widen the gap between “experts” and “the rest”.

Evidently that key and influential group of pseudo-scientists, the astrologers, have no plans to downgrade Pluto, they assert that it still dominates Scorpio. It is a worrying reflection of the poor standing of science that I suspect many people will be as willing to believe their star signs as the astronomers.

Comments

[Margo Schulter]

A possible compromise does occur to me which would recognize the points of both sides in the IAU debates.
Following a distinction in the biological discipline of taxonomy, one might define the eight "planets" of the new IAU definition as "planets _strictu sensu_" -- that is, planets in a strict or narrow sense.
Then one could define these eight planets plus Pluto and other "dwarf planets" as "planets _sensu latu_" -- that is, planets in a broad sense.
In other words, Pluto (and other dwarf planets) could indeed properly be called planets "broadly speaking," while "strictly speaking" there would only be only eight planets (as under the newly adopted resolution).
Borrowing the sensu strictu/latu distinction seems especially appropriate to me, because in biology it can address a situation where the historical concept of a given species, for example, has become narrower as scientific knowledge progresses; the "broad" and "narrow" definitions recognize both familiar usage and current refinements.
Another possible compromise: how about calling the two categories of planets (sensu latu) "major planets" and "dwarf planets"? The term "major planet" might have more familiarity and resonance than the proposed "classical planet," and adoption of this term would retain the recognition that Pluto, originally considered the ninth major planet, is now agreed to be in a different and intriguing class -- arguably a promotion.
A benefit of the heated debate, and the issues raised on all sides, would be to recognize that in science some taxonomic decisions can be knotty questions; and that it is possible, without discounting in any way the dynamicist perspective of the current new definitions, to recognize the broader sense of "planet" (including Pluto and reinstating Ceres) as well.
If one goes with "major planet" and "dwarf planet," then this revision would also fit the view that a "dwarf planet" is a kind of planet -- broadly speaking, of course.

[Surinder]

An example perhaps of this group of so-called experts not being the best judge on the issue? But should we go to the other extreme and throw it out to non-experts and exploit the Wisdom of Crowds?