We’re now beginning to see widespread reaction to the International Astronomical Union’s newly-adopted planetary guidelines, from scientists, astronomers, and the general public. Some argue that the end result makes sense both logically and scientifically, given that Pluto’s characteristics tend to distance it from our more prominent planetary neighbors. Others staunchly oppose the verdict, incensed by the move which stripped Pluto of its status after three quarters of a century.

Granted, the revised definition adopted by the IAU has not addressed all of the pertinent details, and some of the wording is vague. Most notably in my mind: the efforts to hammer out a workable list of planetary attributes made no attempt to tackle the issue of extrasolar planets, something highlighted by Sky & Telescope senior editor Robert Naeye. Further, as Space.com senior science writer Robert Roy Britt points out, there appear to be unresolved issues concerning nomenclature for the newly-formed class of “dwarf planets.” Convention thus far has traditionally named planets and their satellites after figures from Roman and Greek mythology. It’s not yet clear how that process will proceed. Hopefully more light will be shed upon these aspects in short order.

Make no mistake, though — the IAU had to complete the absurd task of assigning specific, scientific meaning to a word borne of culture. There was no ideal solution to the problem, no escaping some degree of arbitrary content. Had we been provided with a list of 8 planets, or 12, or 53, regardless of where lines were drawn in the cosmic sand - or - had the situation ended in a stalemate, leaving us with the same roster of 9 planets we had last week, the astronomers would still have been scrutinized with spiteful eyes. It was a no-win situation no matter how you slice it.

I’m at a total loss to grasp the negative outcry, including a number of sheerly vitriolic comments which have surfaced on the Internet and its blogosphere. What reasons exist for this selfish, persistent cultural attachment? How have these outspoken opponents to Pluto’s new label become so emotionally bound to the issue? I can empathize somewhat with the feeling of reluctance to change, however, some are treating the situation as if Pluto has ceased to exist entirely, a sentiment apparently regurgitated by certain media outlets which portray these latest astronomical developments in the worst possible of ways.

A few angry voices have gone so far in their discontent with the IAU’s ruling as to proclaim that NASA’s New Horizons mission, which launched this January and is currently en route to Pluto for a scheduled rendezvous in July of 2015, is now somehow devoid of meaning. This couldn’t be further from the truth, as the mission in my eyes takes on newfound importance — its study of the Plutonian system and beyond will not only yield invaluable data, but also help cement the criteria by which an entirely new class of objects will be judged.

Others, in sneering at Pluto’s demotion, have launched emotionally-fueled salvos like “Well, Clyde Tombaugh would be spinning in his grave right now if he knew.” I’ve seen this same comment in a number of venues now, and it seems terribly out of place. The 93-year-old widow of Pluto’s famed discoverer, Patricia Tombaugh, doesn’t share that sentiment. She states:

He was a scientist. He would understand they had a real problem when they start finding several of these things flying around the place. ¹

It’s disappointing in a way, and confusing. But I understand science is not something that just sits there. It goes on. Clyde finally said before he died, ‘It’s there. Whatever it is. It is there.’ ²

Even the Lowell Observatory - the facility where Clyde Tombaugh discovered Pluto - has posted a positive, conciliatory statement:

Today in Prague the IAU has adopted a new definition of the term planet in our solar system. Under this definition, Pluto and similar objects in the Kuiper Belt are now classified as “dwarf planets.” One thing is clear: while the label for Pluto may have changed, the object itself has not. It remains a fascinating world in an intriguing realm of the solar system. Pluto has an atmosphere, a family of moons, and evolving surface features. Lowell Observatory is continuing the work to gain a better understanding of Pluto and the Kuiper Belt.

Let’s take a moment to put things in perspective. Look closely at the following images.

These smatterings of pixels represent the best effort thus far at imaging Pluto’s surface. It’s a small, chilly world, a mere two-thirds the size of our Moon, but almost 12,000 times farther away — residing some 4.6 billion kilometers from where you sit reading this text. It’s too small and too far away to be resolved by the largest telescopes on Earth or orbital observatories like the venerable Hubble Telescope, which took these pictures. We have no maps, no list of features with which to identify, like Valles Marineris on Mars, Jupiter’s famous Great Red Spot, or other perennial favorites. We have much to learn.

Whether you’re pleased with the IAU’s new planetary criteria or not, try to keep these concepts in mind. What we may or may not find culturally appealing or emotionally satisfying has no bearing on the magnificent self-correcting nature inherent to the scientific method. It greatly behooves us not to fall prey to shortsightedness. We’ve weathered numerous and far more tumultuous transitions historically, from the geocentric models favored in classical antiquity, to the heliocentric view; from thinking at one point that the entire universe was confined to what we now know to be the Milky Way, realizing that it’s only one of billions of galaxies in the cosmos.

As I’ve spent time penning my thoughts and observations here, the legendary Carl Sagan’s words have been bouncing around in my head. In the course of explaining our species’ propensity for historically maintaining a vastly inflated sense of self-importance, he made the following remarks in chapter three of Pale Blue Dot, entitled, appropriately enough, The Great Demotions:

The long-standing view as summarized by the philosopher Immanuel Kant, that without man, the whole of creation would be a mere wilderness, a thing in vain, and have no final end — is revealed to be self-indulgent folly. A principle of mediocrity seems to apply to all our circumstances. We would not have known, beforehand, that the evidence would be so repeatedly and thoroughly incompatible with the proposition that human beings are at center stage in the universe. But most of the debates have now been settled decisively in favor of a position that, however painful, can be encapsulated in a single sentence. We have not been given the lead in the cosmic drama. Perhaps someone else has. Perhaps no one else has. In either case, we have good reason for humility.

Life and science shall continue. Let’s get on with both.

Further reading:

• Goodbye, Pluto. Hello, “Dwarf Planets”! - SkyTonight.com
• Honey, I Shrunk the Solar System - JPL
• And Then There were Eight: IAU Vote Shakes Up the Solar System - The Planetary Society
• Xena Awarded “Dwarf Planet” Status, IAU Rules; Solar System Now Has Eight Planets - Caltech
• Johns Hopkins Astronomers React to Pluto’s Planetary ‘Demotion’