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November 23, 2010

"Should Pluto Be A Planet After All?"

After recalculating Eris' size, astronomers find that it is, in fact, not larger than Pluto. Astronomers on both ends of the spectrum give their views.

Some astronomers argue that Pluto, along with many other Kuiper Belt objects, should not be named planets, because of their many different characteristics from the eight currently recognized planets. "The dwarfs' orbits tend to be very different, much more elliptical and more inclined, relative to the plane of the solar system. And they're made of different stuff, with ices comprising more of their mass," the article states.

Alan Stern's view, "a planet is anything that meets the IAU definition's first two criteria — the bits about orbiting the sun and having enough mass to be roughly spherical, without the "clearing your neighborhood" requirement."

...But this definition would largely expand the solar system to include many more bodies in space as planets.

"Brown thinks stripping Pluto of its planethood doesn't make the icy body any less interesting or important. 'I think that Pluto as an example of a large Kuiper Belt object is so much more interesting than Pluto as this very weird planet at the outer edge of the solar system unlike anything else,' Brown said. 'We are going to learn so much more about the solar system with our new understanding of what Pluto is.'"

Given this information, do you believe Pluto should be reinstated as a Planet? Why or Why not?


Posted by elizroge at November 23, 2010 03:22 PM


I found this article pretty interesting because in class, we covered why Pluto wasn't a planet, whereas this article presents both sides of the argument. However, I still wouldn't call Pluto a planet because it doesn't clear out the space around it and its composition.

Posted by: taypogue at November 29, 2010 07:52 PM

I don't believe Pluto should be reinstated as a planet. I agree with Stein when he says that Pluto will gain more respect and aspects of interest by being a large Kuiper Belt object instead of a strange planet. I however, don't believe it is fair to science and the public to keep confusing everyone with the "is it or is it not" question. It isn't fair to keep the public in the dark, but rash decisions should be made when the information is clear. I believe that, If Pluto is made of something totally different from all the other planets, then it is, in fact, not a planet. I'm still confused about the IAU's definition of what a planet is, and I think it should be changed due to new circumstances

Posted by: rahoro at November 30, 2010 01:39 AM

I think people are putting too much emphasis on the classification of certain bodies in our solar system. I agree with Brown, in that, I think Pluto will continue to be interesting and we will continue to learn from it, regardless of if it is recognized as a "dwarf planet," "planet," "comet," whatever. I did find it interesting, however, that Eris is not larger than Pluto. The exponential rate at which our technology is advancing is totally unbelievable and I predict we will make a lot more discoveries about our solar system and the bodies within it in as short a time as the next five years.

Posted by: lcav at December 1, 2010 03:46 PM

I also think that Pluto should not be considered a planet. The more advanced our technology becomes, the more we'll discover other objects similar to Pluto that fulfill the first two qualifications for planets. Already, Ceres in the asteroid belt is large enough to be spherical. If we ignore the criterion of a cleared out orbit, we would have at least ten planets.

Additionally, why does the labeling matter so much? In learning about the formation of the solar system and other important questions facing astronomers, how does a mere name make any difference? It almost seems as though those most affected by the change are the children forced to relearn a new sentence to memorize the planets. Pluto is interesting enough in its prior classification as a planet. The changes that have come over time show just how much progress has been made.

Posted by: lebeisma at December 1, 2010 11:21 PM

Wasn't one of the main reasons why it was considered not to be a planet it's size? Although it has not cleared out if orbital path, astronomers should still take this new evidence into consideration when determining whether or not to reinstate it. If they decide to reinstate Pluto as a planet according to Steins definition, then many more bodies would be considered planets at well. Basically, scientists need to determine the line between a planet and non planetary solar objects to stop confusing themselves and all of us.

Posted by: arieloz at December 3, 2010 12:57 PM

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