10 March 2009

Illinois Legislature Restores Pluto's Planetary Status

Well, I'm glad that's been settled. After the IAU's demotion of Pluto a few years back, I've been waiting for this. The floodgates of formal opposition have opened. The dam has burst.

First up was the trailblazing New Mexico Legislature, back in 2007, which passed the following:
WHEREAS, the state of New Mexico is a global center for astronomy, astrophysics and planetary science; and
WHEREAS, New Mexico is home to world class astronomical observing facilities, such as the Apache Point observatory, the very large array, the Magdalena Ridge observatory and the national solar observatory; and
WHEREAS, Apache Point observatory, operated by New Mexico State University, houses the astrophysical research consortium's three-and-one-half meter telescope, as well as the unique two-and-one-half meter diameter Sloan digital sky survey telescope; and
WHEREAS, New Mexico state university has the state's only independent, doctorate-granting astronomy department; and
WHEREAS, New Mexico state university and Dona Ana county were the longtime home of Clyde Tombaugh, discoverer of Pluto; and
WHEREAS, Pluto has been recognized as a planet for seventy-five years; and
WHEREAS, Pluto's average orbit is three billion six hundred ninety-five million nine hundred fifty thousand miles from the sun, and its diameter is approximately one thousand four hundred twenty-one miles; and
WHEREAS, Pluto has three moons known as Charon, Nix and Hydra; and
WHEREAS, a spacecraft called New Horizons was launched in January 2006 to explore Pluto in the year 2015;
NOW, THEREFORE, BE IT RESOLVED BY THE LEGISLATURE OF THE STATE OF NEW MEXICO that, as Pluto passes overhead through New Mexico's excellent night skies, it be declared a planet and that March 13, 2007 be declared "Pluto Planet Day" at the legislature.
Second up, the Illinois General Assembly, which has enacted the following text into law:

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.
Personally, I'm a fan of the hydrostatic equilibrium (i.e. spheroidal) definition which results in 13 planets currently and likely more than 100 eventually, since any other definition which includes Jupiter and Mercury (not to mention Earth), is flawed in some way. That said, simply using hydrostatic equlibrium would not exclude any spheroidal moons. There was a fun debate on this at Mike Brown's blog last September.

In the end, I think the unsaid part of the planetary controversy is the desire for Earth to be a capital-p Planet, and not a "minor" or other adjectively-modified flavor. As long as there's big gas giants like Jupiter and Saturn out there, that'll make things difficult.


Laurel Kornfeld said...

The hydrostatic equilibrium argument is the one that makes the most sense.

The Illinois legislature 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.

Stewart Bushman said...

Laurel, Between your comments on Mike Brown's blog and your LiveJournal Pluto Blog, I'm not sure if I've read anyone more passionate on this issue than you are, and I know Alan.

Shel Purim :)

FrankG said...

Allow me to come at this from a different angle...I don't want to get into the pluto planet/not a planet debate. That's something for folks who know a lot more about astronomy than me to debate and decide...and that's the point. It's not for me or other lay people (admittedly, I've got a PhD in Aerospace Engineering - but that just shows I know how much I don't know) and ESPECIALLY NOT POLITICIANS to try to legislate scientific fact.

It sets a dangerous precedent. Imagine what your reactions would be if "Pluto...be declared a planet" was replaced with "Intelligent Design...be declared scientific fact".

Science is not a Democracy...just because a majority of people (or legislators) want something to be a scientific fact, doesn't make it so.

I now return you to your previous discussion of the virtues of Pluto, already in progress.

Laurel Kornfeld said...

FrankG, I disagree with your statement that "its not for lay people" to get into this debate. The exact opposite is true. It is not only professional astronomers who have a stake in this or an interest in this. We're talking here about an interpretation of the facts, not the facts themselves. The universe and the solar system are the heritage of all of us, not just those with PhDs in astrophysics. Getting people interested in and engaged with this debate is a positive thing; it gets people thinking and learning about something they otherwise would never think about. And it also assures that if scientists are making decisions more motivated by politics than by science, at least there will be others out there to call them on this and not just blindly accept some decree.

Just because four percent of the IAU vote on something doesn't make it a fact either. Ideas rise and fall based depending on how well they hold up over time. Alan Stern correctly pointed out that no one voted on the theory of relativity or any other scientific theory, so why a vote on this?

Stewart Bushman, I'm passionate about any conviction to which I hold strongly; that's just my nature. I doubt my passion on this issue exceeds that of Alan Stern or Mark Sykes; they're just better at articulating their positions than I am and have the professional credentials to do so much better than I do.