On yesterday’s Rachel Maddow show, guest Neil deGrasse Tyson- astronomer at the Hayden Planetarium – confirmed again his position that Pluto was indeed “demoted” from planetary status, and then proceeded to try to explain why. This also provided air time in advance of his PBS program: ‘The Pluto Files: The Rise and Fall of America's Favorite Planet', chronicling his experience at the center of the controversy over Pluto's planetary status.
My issue then as now is WHY did this controversy arise in the first place? Also why confect an artificial definition for a planet – e.g. “it must clear its orbital zone around the Sun” – when the definition itself is obviously based on trying to demote Pluto? (Somewhat analogous to the BLS definition of the “unemployed” – which drops everyone still unemployed after 6 months as “discouraged?) Pardon me, but I have strong issues with tampering with people’s neural networks and language centers via euphemisms, lies and cynical manipulations.
The issue here isn’t so much about being exercised at Pluto’s demotion, as the gravitas which we attach to language and especially scientific procedures and processes. The bottom line is that Pluto’s dethroning was done by a subjective vote at an IAU meeting, not by any objective measures or consistency. (Though doubtless deGrasse Tyson would argue otherwise).
But let’s examine it more closely.
As it turns out, Tyson’s Hayden predecessor – Dr. Kenneth R. Franklin- during a 1975 stopover at Barbados (and after giving a guest lecture at its Harry Bayley Observatory), was asked a question on the possible demotion of Pluto. The questioner wanted to know, given we knew so little about Pluto (Viking hadn’t even landed on Mars yet) whether a possible demotion to a comet or asteroid might be in the works if we discovered it was much smaller than then believed. (At that time, it was presumed to be about 3600 miles in diameter or about the size of Mercury).
Franklin’s answer – which I captured on audiotape- was clear and distinct:
“That depends. If someday it’s found that Pluto is only half as large as Mercury or even less, BUT if it’s found around the same time to have satellites of its own, then it is still a planet.”
Thus in one clear concise definition, Franklin disclosed how and why even a planet found to be much smaller than originally thought, can retain its status. And, of course, the Plutonian moon Charon was discovered in 1978, just three years after Franklin’s visit, while two other moons – Nix and Hydra- were found in 2005.
Another definition of a “planet” was offered by Dr. Isaac Asimov, both in his book, ‘The Collapsing Universe’ and in his own February 6, 1975 lecture at Queen’s Park Theater in Barbados. The definition was that a legitimate planet is gravitationally attracted to the Sun more than it is to any ancillary satellites or Moons it may possess. In doing some back of the hand math on a chalkboard, Asimov actually showed the Moon is a planet in its own right, since it is attracted more to the Sun than to the Earth. If he was alive and could do similar calculations for Pluto – I know he’d also concur it was a planet.
But let’s go back to the absurd definition that a true planet has nothing substantial crossing its path as it orbits the Sun. The problem is the definition overlooks the neighborhood of the object! Pluto just happens to be in the Edgeworth –Kuiper belt with thousands of other objects. This is a condition of happenstance, not of actual intrinsic property.
If Earth were to interchange its position with Pluto it would also be in the same belt, and because other substantial objects (e.g. Neptune) crossed its path, it would have to be demoted – by deGrasse Tyson’s definition. So what to call it, a “demi-Earth”? A jumbo dwarf planet or jumbo shrimp planet? Give me a break!
In the end, the error of the planetary astronomers in the 2006 confab was to cave in to a certain contingent of peer pressure to avoid “complexity”, e.g. in adding numerous additional planets like Charon, Xena, Ceres etc. This, despite the fact the original IAU definition was perfectly rational in its criteria for a planet.
Alan Stern, executive director of the Space Science & Engineering Division of the Southwest Research Institute – and Principal Investigator for NASA’s New Horizons mission to Pluto- observed that the new planet definition was “sadly flawed, particularly due to the vagueness of the third condition”, e.g. clearing the neighborhood around its orbit – which might also disqualify Earth!
He added: “A lot of people are going to ignore the (new) definition because it doesn’t make sense.” (Source: Eos Transactions of the American Geophysical Union, Vol. 87, 29 August, p. 350)
Again, this isn’t about getting into a pickle over definitions specifically, but attending to the objective processes of science – especially in an era in which denialism is rampant, and looking for any excuse to reject critical findings – such as anthropogenic global warming.
The tragedy of the Pluto vote and the accompanying contrived definition is that it's not only set back planetary astronomy – showing the preponderance of ego over scientific inquiry – but public confidence in science as well. In such a climate, one can’t be too surprised when spurious crises like “climate gate” arise, since their genesis is directly connected to the lack of attention current scientists are paying to their QA processes and the presentation of their respective disciplines overall.
5 comments:
Categorizing orbiting objects as planets, asteroids, moons, comets, etc, when done for the convenience of working astronomers, need not concern the rest of us. We could also argue about a red blood cell as a real cell or as a cell fragment. Only a few bean counters really care. Why dies it matter if we call Pluto a planet? <-- serious question
As someone actively advocating Pluto's planet status for three-and-a-half years (see my Pluto Blog at http://laurele.livejournal.com ), I wholeheartedly agree with everything you say with one exception. Tyson has never been a supporter of the IAU decision. At several public presentations, including the Great Planet Debate held at the Johns Hopkins University Applied Physics Lab in August 2008 and at the Isaac Asimov Memorial Debate at the American Museum of Natural History in NYC in March 2009, he distanced himself from the IAU decision, which he described as "flawed." Tyson now says he never publicly stated that our solar system has only 8 planets, and in "The Pluto Files," he made it pretty clear that he regards this as an ongoing debate rather than a matter that is settled. It seems he may be coming around to a more neutral viewpoint--not surprising, as the IAU definition is so bad that its weaknesses actually hurt the position of those who voted for it.
John Schmidt wrote:
"Categorizing orbiting objects as planets, asteroids, moons, comets, etc, when done for the convenience of working astronomers, need not concern the rest of us. We could also argue about a red blood cell as a real cell or as a cell fragment. Only a few bean counters really care. Why dies it matter if we call Pluto a planet? "
It matters because scientific methods and processes are important, not because "a name by any other name" means anything....to anyone. (Though saying that people - laymen - "need not be concerned with x, y or z" is imho a disastrous notion which current science (dependent on public funding ultimately, can ill afford.)
If people (laymen) perceive that planetary status (which ought to be an OBJECTIVE finding) is accomplished by subjective vote, then you really can't blame them for buying into the agnotology* message- that consensus, i.e. in the anthropogenic warming setting, means science is decided by popularity. When in fact, consensus in the AGW frame means that most of the peer-reviewed papers published agree than anthropogenic inputs are factors.
The modern consensus on evolution, meanwhile, was achieved by a body of empirical evidence, including from the fossil record, microbiology and genetics- and by passing all its primary tests for falsification.
Mathematical precision also consolidates scientific discovery in quantitative fields, making them less likely to be overturned or subject to perceived whim. Particle physics is one such example, wherein the original three sub-atomic particles (proton, neutron, electron) have now become a veritable “zoo” numbering in the hundreds – including up, down, top and bottom quarks, W and Z bosons, electron, mu and tau neutrinos and many others too numerous to mention.
This panoply of particles didn’t just manifest because the respective particle physicists intended to be “mean” (by virtue of added complexity) to school children or regular mortals. It emerged out of more refined and detailed experiments that exposed each of the particles as authentic in their own right.
The same needs to apply in astronomy, to categories of objects of our inquiry - whether they be planets, asteroids, comets or whatever. Failure to adhere to an objective process (even in basic identification) simply means that one relies on subjective perceptions. This again plays into the whole shameful axis of agnotology.*
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* Agnotology (n.) -derived from the Greek 'agnosis' and hence the study of culturally constructed ignorance'. Coined by Stanford historian of science Robert Proctor, who has referred to the trend of skeptic science sown for political or economic ends - e.g. in imparting ignorance and faux skepticism, agnotology. It is achieved primarily by sowing the teeniest nugget of doubt in whatever claim is made.
Proctor notes that when a society doesn't know something it is often because special (often paid) interests have worked hard to sow immense confusion on the issue. People read 'A' then see 'B' ostensibly refuting it, and without a hard science background themselves.
My point (again) is that lack of an objective process - say in identifying planets- plays into the hands of those who would reduce science largely to a matter of ideology, popularity or politics. In the end, all of science, every discipline, pays a fearsome price.
Laurel Kornfield wrote:
"I wholeheartedly agree with everything you say with one exception. Tyson has never been a supporter of the IAU decision"
Okay, thanks for clarifying that as I thought he was, based on his comments on the Rachel Maddow show.
I do hope, as you suggest, that he tempers his position to one of at least greater neutrality over time.
I also hope that the IAU can eventually arrive at an objective definition of "planet" that everyone can agree on, and which will include the Moon (as part of our double planet system) and Pluto!
"... saying that people - laymen - "need not be concerned with x, y or z" is imho a disastrous notion which current science (dependent on public funding ultimately, can ill afford.)"
I wholeheartedly agree--saying lay people "need not be concerned with such matters" essentially amounts to an authoritarian mode of thinking, where a self-selected small group of "elites" make decisions, not necessarily based on science, that everyone else is expected to follow. Classification schemes, theories, etc. should rise or fall on their own merits, not because a group issues a decree. Do we really want a dichotomy where a small group of professionals is concerned with science, and everyone else just blindly accepts their decisions? That is the opposite of promoting independent inquiry and thinking. Clearly, more than "a few bean counters" care about what we call Pluto, and this is a good thing. It means they are paying attention to astronomy and have the discretion to distinguish a poor definition from a good one.
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