Randy Cassingham's Blog

Long-time readers know I have a special place in my heart for the planet Pluto. It's not just that I spent 10 years working at NASA's Jet Propulsion Laboratory, and worked on the precursor project to the probe that's on the way there now. One of my earliest memories is going to the Griffith Observatory (I grew up in L.A. for the first 10 years), and insisting that I be allowed to buy a photograph of the outer planets at the gift shop. I remember Jupiter and Saturn being very clear, and Neptune being a bit fuzzy, and each taking up a quarter of the 8x10 print. In the fourth quarter: a field of stars with an arrow at a point of light labeled "Pluto". I wanted to know why we didn't have a much closer view! (This was definitely several years before Apollo.) I indeed was allowed to get the photo, and I had it for many years. Sadly, it disappeared during one of my moves.

In May 2002, when the approved mission to Pluto was in funding jeopardy, I ran an editorial in True urging readers to support it. I don't know if my editorial helped, but the mission's Principal Investigator, Dr. Alan Stern, thought it did. He not only said thank you, I was very pleasantly surprised to be invited to the mission launch from Cape Canaveral last year. As a JPLer I had been to a couple of Space Shuttle landings in the California desert, but never to any launches. I got the invitation extended to Kit, and we both went, and I shared my experiences with you.

This week I got another note from Dr. Stern. He is mightily bothered that the International Astronomical Union voted last August to adopt a new definition of "planet" to exclude Pluto. He thinks it's a mistake, and so do I. Tomorrow (March 13, the day in 1930 that the IAU announced the discovery of Pluto by Clyde Tombaugh of New Mexico) has been proposed by the State of New Mexico to be "Pluto Planet Day" to both recognize Tombaugh's discovery and to express displeasure at the IAU's new definition.

It's not just politicians (and the public) who disagree with the IAU; apparently a majority of scientists do too, including Alan Stern, who notes that if it's strictly applied, even Earth doesn't meet the IAU's definition of "planet"! Who else disagrees? The European Geophysical Union, which has voted to come up with its own definition at its annual meeting next month, and the American Association for the Advancement of Science. "EGU and AAAS are both much larger professional organizations of scientists than the IAU," Stern told me in an e-mail. "I see this as strong empirical evidence that the IAU definition is fatally flawed and other scientific organizations are now stepping up to the plate to repair the situation IAU has created. The IAU has lost the confidence of too many scientists in this, and science is moving on to forge a better consensus. The IAU can choose to catch up later if it so desires."

So why, really, does it matter? It does matter, and here's why: Pluto is the tip of a huge iceberg, an entirely new class of objects that make up the Kuiper Belt, where there are perhaps 100,000 planetoids, with as many as 1,000 of those being the size of Pluto. IAU seems to be afraid that planets will not be "special" if there are a thousand or more bodies with the title; they're just these rocky, icy things way out there; they're ordinary, not worthy of a second look.

Well, I'm of the opposite mind: we now know our solar system doesn't just have nine planets, but more than 1,000, and with that comes the realization that we've only explored eight of them! We're hugely ignorant of our surroundings even in our tiny corner of the galaxy. Without fail, every time that we've sent probes to other planets we get big surprises: we learn new things not just about those planets, but about the solar system, the galaxy, and the universe in general. And what's the point of existing if we're not exploring and learning new things? "The cost?" you might ask. In 2002 I pointed out the Pluto probe cost about one-quarter of what we spent that year on ...Easter candy. Fundamental knowledge is worth far more than that.

We pompous humans need to understand that we occupy a minutely tiny part of the universe. It does us good to stand in awe with our eyes open to the vast amount and diversity of things that are not right in front of our noses. The label "planet" should be reserved for the most special things around us? You bet. Those 1,000-100,000 bodies in orbit around our sun are a part of the neighborhood and we should understand them better. They are special. And we know nearly nothing about them, and shame on us for our ignorance: it's time we knew more. By taking away the label "planet" from Pluto and similar bodies, the IAU is sending a message that these bodies are not special, they don't need to be looked at, it's not important that they be understood. But the reality is, we have no idea whatever how special they are, and the only way to find out is to go look and learn. And I have great faith that like every time in the past, we'll be surprised by what we find, and understand the universe that much better. We're not talking about the interest of a few planetary scientists, we're talking about expanding human knowledge and expanding the understanding our place in the universe. That's "special" indeed, and our language needs to reflect that.

And a quick aside, as long as I'm on the subject: Alan Stern, whom I now count as a friend, has just accepted a new job. He's currently employed by the Southwest Research Institute, which is managing the Pluto project. He has accepted an offer to be the new associate administrator for NASA's Science Mission Directorate -- the nation's top space scientist in charge of NASA's $5 billion science budget. He accepted the offer when NASA assured him he can still work on the Pluto probe. I can't think of a better person for the job to help us understand the importance of learning more about our surroundings. Congrats, Alan!