August 6, 2009
Dear Dr. Cesarsky, Members of the IAU Executive Committee, Members of the
Secretariat, Members of the Working Group on Planetary System Nomenclature,
and Delegates to the 27th IAU General Assembly,
I am writing to urge this General Assembly to officially reopen the planet definition issue, in light of the tumultuous, controversial, and abrupt manner in which it was addressed at the 26th General Assembly in 2006. Specifically, I ask that you reconsider and add Resolution 5b from 2006, which would establish “planets” as a broad, umbrella category under which both classical and dwarf planets would be included.
Doing this amounts to reconsidering a simple amendment that, if adopted, would supersede the 2006 vote on this resolution and thereby establish dwarf planets as a subcategory of planets.
Additionally, I urge you to place a resolution on the table to allow electronic voting on all resolutions by all members of the IAU, for the purpose of including the voices of astronomers who for various reasons, including financial difficulties and family responsibilities, are unable to attend the two-week General Assemblies in person. This will make IAU processes more inclusive of its membership and bring them in line with the digital reality of the 21st century.
Undoubtedly, you are all aware that a significant number of planetary scientists and professional astronomers, as well as amateur astronomers and interested members of the public, have been dissatisfied with the IAU planet definition adopted in 2006. That is why I and many others are asking that a better planet definition be adopted, specifically one that includes exoplanets in its classification system and also reassigns dwarf planets as a subcategory of planets, as had been proposed by 2006 resolution 5b.
This is not about Pluto; it is about the need for a more useful, clear definition that encompasses both dynamics and planetary geophysics. The 2006 definition fails to do that on two counts. First it states that dwarf planets are not planets at all, which is inconsistent with the use of the term “dwarf” in astronomy, where dwarf stars are still stars, and dwarf galaxies are still galaxies. This results in blurring the crucial distinction between those objects located in belts but in hydrostatic equilibrium, with shapeless asteroids. Second, it defines objects solely by where they are while ignoring what they are. If Earth were in Pluto’s orbit, according to this definition, it would not be considered a planet either. A definition that takes the same object and makes it a planet in one location and not a planet in another is essentially unusable.
Additionally, the process through which the 2006 definition was adopted was flawed, as it violated the IAU’s own bylaws requiring such a resolution to be first vetted by the appropriate committee before being put on the General Assembly floor, a practice not done in this case.
With planetary science still in its infancy, it is understandable that first attempts at defining terms such as planets will be difficult and may need reconsideration. In that light, the 2006 resolutions represented a good, valiant first attempt in this direction. There is no shame, however, in admitting that this first step is flawed to the point of requiring amending. Specifically, the requirement that an object “clear the neighborhood of its orbit” to be considered a planet is vague; if taken literally, it most certainly excludes Neptune, which does not clear its orbit of Pluto and could also be construed to exclude Earth, Mars, and Jupiter, which share their orbits with large numbers of asteroids.
Significantly, only 424 out of 10,000 IAU members took part in the 2006 vote, and of those, only 237 approved the 2006 planet definition resolution. In no way can this be considered a majority consensus. It is noteworthy that immediately, hundreds of professional astronomers around the world, led by Dr. Alan Stern, Principal Investigator of NASA’s New Horizons mission to Pluto, signed a formal petition rejecting the IAU decision entirely, adding that they will not use it.
A conference titled “The Great Planet Debate,” held in August 2008 at the Johns Hopkins University Applied Physics Lab, focused solely on planet definition, with open discussion of the fine details representing both the views of dynamicists and planetary geologists on this issue. Even among dynamicists, there was consensus that the 2006 decision needs to be amended. This same view was unanimously upheld at the Isaac Asimov Memorial Debate, “From Planets to Plutoids,” held in March 2009 at the American Museum of Natural History in New York City, where six panelists (three dynamicists and three planetary scientists) and moderator Dr. Neil deGrasse Tyson all agreed that a better planet definition is needed.
In her opening statements to the 27th General Assembly, Dr. Cesarsky noted that while 142 nations are participating in the International Year of Astronomy, only 63 countries are national members of the IAU. I ask that you consider the possibility that this notable difference results from a dichotomy in public perception: much of the general public is fascinated with astronomy, but many have lost respect for the IAU, not because of Pluto, but because the IAU’s decision-making processes appear to be driven more by politics than by science.
In the GA newsletter “Estrela D’Alva,” on August 4, 2009, discussion of a decadal plan to stimulate astronomy education around the world opens with the statement, “the IAU regards stimulating astronomy education and development throughout the world to be one of its most important tasks.” This is in line with the IAU goal of “safeguarding the science of astronomy” and communicating astronomy with the public.
Communicating with the public means listening to members of the public. It is a two-way street. Members of the public around the world, not just in the US, feel disenfranchised and ignored by the IAU planet definition resolution, both in its process and outcome. As an amateur astronomer, writer, and astronomy student, I have personally experienced, both in person and online, this dissatisfaction and disconnect that ultimately turns people away from science, thereby defeating the goals above. Among those most dedicated to astronomy, large numbers worldwide are dissatisfied with the 2006 decision, and many refuse to use it. How will the IAU successfully raise funds needed for its planned Global Development Office and general decadal plan if its processes are alienating so many potential donors?
That is why, to further respectful two-way communication with the public, I urge the IAU to also actively seek input on important issues such as this one from a broader population, including professional astronomers who are not IAU members, amateur astronomers and groups representing them, and astronomy students at all levels.
If the IAU continues to deny that a controversy remains over planet definition and the 2006 resolution in spite of clear data to the contrary, the organization risks becoming less and less relevant and less and less influential on astronomical matters. In the US, a guiding principle is that government operates by consent of the governed, and that the people can withdraw that consent at any time should an existing government begin conducting itself in an unsatisfactory and tyrannical manner. The IAU claims to be the governing body on all celestial objects and phenomena. In this light, the IAU should very strongly consider that public and scientific consent to its dictates are not absolute and may be withdrawn at any time if enough people view the organization as irrelevant or as failing to do its job in “safeguarding the science of astronomy.”
Should the IAU fail to appropriately deal with this issue and the broader question of its closed decision-making process, it is inevitable that other groups and individuals will emerge to fill that void, further eroding the IAU’s credibility and respect in the field of astronomy.
Therefore, regardless of the fact that no action on this issue has been planned for this General Assembly, I implore the IAU’s leadership, delegates to the GA, and members to do what needs to be done, to show courage and sensitivity to both scientists and lay people in admitting the planet definition issue remains unresolved and place a resolution on the General Assembly floor for a vote on August 13, 2009, which will officially adopt resolution 5b of 2006 and establish dwarf planets as a subclass of planets. I further ask a resolution allowing for electronic voting be adopted before any other resolutions are considered to allow the IAU’s full membership to vote on all relevant issues.
Laurel E. Kornfeld
Highland Park, NJ, USA
Writer, amateur astronomer, astronomy student and blogger