Resurrection:
Pluto a planet once more!

Jesmeen Deo
Contributor

ight years after Pluto was demoted from its planetary status, there may be hope again as
the scientific debate about whatxactly constitutes a planet has once again entered public
discussion.

In 2006, Pluto was demoted from its planetary status and reclassified a dwarf

planet. Childhoods all over the planet were ruined, there was outrage from some
astronomers in the scientific community, and the mnemonic “My Very Eager Mother
Just Served Us Nine Pizzas” was dismembered. It was a terrible tragedy.

Even now, people of all ages are still passionate about Pluto. In September at the
Harvard-Smithsonian Centre for Astrophysics, a debate (not unlike the one that
demoted Pluto in 2006) took place. As reported by TIME magazine, the Harvard vote
supported Pluto’s reinstatement, and that debate has sparked another open dialogue.

Harvard scientists who argued for Pluto’s reinstatement said that the rules for classifying planets

were flawed. The International Astronomical Union (IAU) set these arguably convoluted rules, which
claim a planet must: (1) be in orbit around the sun, (2) be big enough to be pulled into a sphere by its
own gravitational force, and (3) have a cleared orbital ‘lane’ around the sun all to itself. According to the
2006 debate that led to Pluto the Planet’s sad demise, Pluto fails to measure up to the third condition.

There are, of course, legitimate arguments on the IAU’s side.

If, say, Pluto were reinstated, then other dwarf planets similar to Pluto would also have to be included, like Eris,

which is of similar size. Gareth Williams of the IAU argues that this would increase the number of planets to 25

or so, and as the years go on it could go to 100. “Do we want schoolchildren to have to remember so many? No, we

want to keep the numbers low.” This argument does have merit; it cannot be denied that the planets are a huge part of
basic scientific learning for children. From a scientific standpoint, the argument “it’s just easier this way” does not stand.

In the recent debate, the Harvard astronomers waved the definitions aside and kept a few basic contentions against the IAU decision.

One scientist reasoned that yes, we do need a clear-cut definition for planets, but we are still too ignorant in the field of astronomy to

make one; and so, for the time being, Pluto should arbitrarily be kept on the list. Another argument brought up by the Centre’s communications

director, David Aguilar, was “Isn’t a dwarf fruit tree still a fruit tree? Isn’t a dwarf rabbit still a rabbit?” And lastly, Owen Gingerich, a Harvard historian,

said that the definition of a planet has become more cultural than scientific. After all, the overwhelming support in polls over the years has been for Pluto’s reinstatement.

The general opinion seems to support the idea that what the IAU thinks is irrelevant. To the general populace, the classification of a planet has indeed become a cultural definition.

Asa side note, during the infamous 2006 vote, most of the 10 000 IAU members had gone home, leaving only 424 of them to actually cast a ballot. After the vote was taken, the members
were asked if they wanted to take a revote, but according to what Gingerich told TIME, “they voted not to vote again, because they wanted to go to lunch, and that was the end of it.”

That lack of thoroughness seems pretty contrary to the scientific method, but that’s a discussion for another day. For now, the international debate
has been re-ignited, and we have hope for when the big IAU conference reconvenes next summer. Pluto is (possibly) back, baby!