Illinois Senate Battles for Planet Pluto

Dwarf planet Pluto
The Dwarf Planet Pluto

The Illinois 96th General Assembly (2009-2010) fresh from demoting Governor Rod Blagojevich to non-governor status is out to balance things out by promoting Pluto back to planetary status. Clyde Tombaugh (1906-1997), the man who discovered Pluto on January 23, 1930, was born in Illinois. Up until the time that the International Astronomical Union demoted Pluto to a dwarf planet (2006), not only could the United States boast of having a native born planet discoverer but so could Illinois. Being a native Illinoian myself I rather liked that. I even had the honor of meeting Clyde Tombaugh quite a few years ago and have an autographed copy of his book Out of Darkness: The Planet Pluto, co-authored with Patrick Moore.

Up until the International Astronomical Union's 2006 meeting there had never been a formal definition of just what constituted a planet – it was one of those intuitively obvious things. The discovery of 2003 UB313 was the straw that broke the camel's back. 2003 UB313 was larger than Pluto! What to do? To declare 2003 UB313 a planet would have opened the door to defining Ceres and other like sized objects as planets. It was felt that there was a need for a new category of objects, with size being just one of the factors. The result was a new class known as dwarf planets, of which there are now five members:

  • Ceres
  • Eris (aka 2003 UB313)
  • Haumea
  • Makemake
  • Pluto

In order to reclaim one of Illinois' claims to fame there is a resolution in the Illinois Senate calling for Pluto to be considered a planet and that March 13, 2009 be declared “Pluto Day” here in Illinois. Following is the resolution that is currently before the Illinois Senate.

SENATE RESOLUTION SR0046 LRB096 04130 KXB 14171 r

WHEREAS, Clyde Tombaugh, discoverer of the planet Pluto, was born on a farm near the Illinois community of Streator; and

WHEREAS, Dr. Tombaugh served as a researcher at the prestigious Lowell Observatory in Flagstaff, Arizona; and

WHEREAS, Dr. Tombaugh first detected the presence of Pluto in 1930; and

WHEREAS, Dr. Tombaugh is so far the only Illinoisan and only American to ever discover a planet; and

WHEREAS, For more than 75 years, Pluto was considered the ninth planet of the Solar System; and

WHEREAS, A spacecraft called New Horizons was launched in January 2006 to explore Pluto in the year 2015; and

WHEREAS, Pluto has three moons: Charon, Nix and Hydra; and

WHEREAS, Pluto's average orbit is more than three billion miles from the sun; and

WHEREAS, Pluto was unfairly downgraded to a "dwarf" planet in a vote in which only 4 percent of the International Astronomical Union's 10,000 scientists participated; and

WHEREAS, Many respected astronomers believe Pluto's full planetary status should be restored; therefore, be it

RESOLVED, BY THE SENATE OF THE NINETY-SIXTH GENERAL ASSEMBLY OF THE STATE OF ILLINOIS, that as Pluto passes overhead through Illinois' night skies, that it be reestablished with full planetary status, and that March 13, 2009 be declared “Pluto Day” in the State of Illinois in honor of the date its discovery was announced in 1930.

One bit of misleading information is the point that only 4 percent of the IAU's 10,000 scientists voted. One thing that must be noted is that IAU membership is for life so included in the total membership number are those individuals who are no longer active in either astronomy or the IAU.

Due to the diverse nature of its mission and the different fields of science involved, the IAU is organized into 12 Divisions, 40 Commissions, and 71 Working Groups and Program Groups. The division that deals with planetary science is the Division III Planetary Systems Sciences which has approximately 1,000 members (active and retired).

So while the vote was open to all attending members, only a fraction would have had a direct interest in the outcome of the vote. It is also interesting to note that the outcome of the official vote was similar in proportion to that of a straw poll of Division III Planetary Systems Sciences members that was conducted earlier that day.

I am all in favor of having a “Pluto Day” and acknowledging the accomplishments of Clyde Tombaugh. This is especially appropriate as 2009 is the International Year of Astronomy. However when it comes to deciding whether an object is a planet or not, I put my faith in the International Astronomical Union and not Illinois politicians.

About the Pluto Illustration

To create the illustration of Pluto for this post I began with an albedo map taken from a Hubble Space Telescope image. I then created a grayscale texture for the planet's, oops make that dwarf planet's surface. I then used hue/saturation and levels adjustment layers to further manipulate the texture and layer styles to fuzz up the dwarf planet's limb. All work was done using Adobe Photoshop.

If you live in Illinois, I encourage you to contact your state Senator and let them know that you are in favor of honoring Clyde Tombaugh and Pluto but I leave it for you to decide whether to support or oppose the attempt to have Pluto classified as a planet.

Ad Astra, Jim

| Return to the Blog Index | This entry was posted on Thursday, February 26th, 2009 at 1:26 pmand is filed under Astronomy.

5 Responses to “Illinois Senate Battles for Planet Pluto”

  1. February 26, 2009 at 11:52 pm

    First, you're wrong about the four percent of the IAU in your statement about inactive members. The IAU has 10,000 active members, and 424 voted on this. No absentee voting was allowed. And many planetary scientists are not IAU members and had no say on this at all.

    The Illinois Senate has way more sense than the International Astronomical Union has shown in two-and-a-half years. It's the IAU who have acted like idiots, with one tiny group forcing a nonsensical planet definition on everyone. The truth is there is NO scientific consensus that Pluto is not a planet. The criterion requiring that a planet "clear the neighborhood of its orbit" is not only controversial; it's so vague as to be meaningless. Only four percent of the IAU even voted on this, and the vote was driven by internal politics. A small group, most of whom are not planetary scientists, wanted to arbitrarily limit the number of planets to only the largest bodies in the solar system. They held their vote on the last day of a two-week conference with no absentee voting allowed. Their decision was immediately opposed by hundreds of professional astronomers in a formal petition led by Dr. Alan Stern, Principal Investigator of NASA's New Horizons mission to Pluto.

    Stern and like-minded scientists favor a broader definition of planet that includes any non-self-luminous spheroidal body orbiting a star. The spherical part is key because when objects become large enough, they are shaped by gravity, which pulls them into a round shape, rather than by chemical bonds. This is true of planets and not of shapeless asteroids and comets. And yes, it does make Ceres, Eris, Haumea, and Makemake planets as well, for a total of 13 planets in our solar system.

    Even now, many astronomers and lay people are working to overturn the IAU demotion or are ignoring it altogether. Kudos to the Illinois Senate for standing up to this closed, out of touch organization whose leadership thinks they can just issue a decree and change reality.

  2. Plaxco says:
    February 27, 2009 at 8:26 am

    Hi Laurel,

    Thank you for your comments.

    As to "you're wrong about the four percent of the IAU in your statement about inactive members. The IAU has 10,000 active members, and 424 voted on this."

    I stand by that statement based on email discussion with an IAU officer. The IAU has approximately 10,000 members – not every member remains active in the field.

    You point out "No absentee voting was allowed."

    This is correct. Only those members who actually attend the General Assembly are entitled to vote. This amounted to around 2500 members, of which some 400 stayed to vote on this resolution. Restricting voting to only those who actually show up is standard – allowing absentee voting is highly unusual. In fact I know of no example of absentee voting other than for general political elections here in the U.S. I've served on four different boards of directors for non-profits and not one of them allowed for absentee voting.

    You say "And many planetary scientists are not IAU members and had no say on this at all." True but the IAU is the official body for dealing with these issues. Making this argument is like saying that Bill Clinton's election in 1996 was a farce because he only got 33 percent of the vote. I'm sure the International Star Registry (the folks you give money to and they name a star for you) would support this reasoning – why should the IAU get a monopoly on naming stars and such. Percival Lowell would also agree because when the IAU got around to assigning names to the surface features of Mars, the names Lowell had arbitrarily assigned were used in only a very few instances.

    Laurel: regarding your claim that "the vote was driven by internal politics. A small group, most of whom are not planetary scientists, wanted to arbitrarily limit the number of planets", can you provide any documentary evidence to back this up.

    As to the IAU's defintion of planets and dwarf planets, even though I'm a JPL SSA and a former member of the AGU, I'll refrain from taking a position one way or another because frankly the depth of my knowledge on the subject does not come close to matching that of the scientists who actually participated in the vote.

  3. Phil Boyce says:
    April 8, 2009 at 4:50 pm

    Laurel wrote:”Kudos to the Illinois Senate for standing up to this closed, out of touch organization whose leadership thinks they can just issue a decree and change reality.”

    Sure, by all means, let's have the Illinois senate decide for us, the people of Illinois, whether Pluto is a planet or not. Maybe at the same time we can have them decide if the Higgs boson exists, and we can get a jump on Cern!

  4. Bob McMinn says:
    April 14, 2009 at 3:58 pm

    If Pluto isn't a planet, then Neptune shouldn't be either! Michael Brown just wanted to get his name in the history books. I hope they do keep him in there – for being an idiot. What makes me really mad is the fact that he was able to make it ‘official'. That's what happens when you take the science out of science.

  5. Plaxco says:
    April 15, 2009 at 10:00 am

    With respect to Bob's comment, for the benefit of others, Michael Brown is a professor of planetary astronomy at the California Institute of Technology and led teams that discovered TNOs/dwarf planets Eris, Sedna, Haumea, Makemake, and others.

    It was the discovery of Eris that brought things to a head as Eris is larger than Pluto. Either the IAU would have to make Eris the 10th planet and leave the door open to adding other similar objects, or they would have to sit down and at long last create a formal definition for just what constitutes a planet.

    In a CNN interview following the discovery of Quaoar, Brown stated: “If Pluto were discovered today, no one would even consider calling it a planet because it's clearly a Kuiper Belt object.” I think there is a lot of truth in that.