should Pluto remain a planet?

Question

The latest reports lean towards no...what do you think?

Answer 1

Well, only for historical reasons. I think the evidence is that Pluto is more like the first of a few asteroid-like bodies that came out of the Oort cloud, and that there may be even bigger ones out there farther out.

If it isn't a planet, then what do we call it?

Answer 2

Scientists are debating the definition of a planet. When doing that, they have to consider not only Pluto and the newly discovered 2003 UB 313 in our solar system, but now they have to think about other stars and the planets around them, too. The possibilities, combinations and variations are endless. The scientists currently seem to be leaning towards defining a planet as any object over 2000km in diameter, which would qualify both Pluto and 2003 UB 313 as planets. I'm ok with this. However, if that turned out being our definition of a planet, what would happen when we discover a little star out there that has only one very tiny "planet" revolving around it, and the "planet" was less than 2000 km in diameter? Hmm.

Answer 3

General question. What makes a planet a planet? Is it the mass? Diameter? Orbit? Distance from the sun?

I would say that the following are minimum characteristics of planets.

1 & 2 below are arbitrary, you may prefer other variables.

1. Minimum Mass. 10^20 Kg. (about 1/100th the mass of Pluto).
2. Minimum Diameter. 1,500 Km (about 900 miles)
3. Orbit. Must be in orbit around a sun, and not a planet (therefore, Luna is not a planet, even though it's larger than Pluto).
4. Distance from sun. Not relevant, as long as it is clearly in orbit around the sun. Therefore, a massive sun may have planets dozen's of light-years away.
5. Is not itself a sun. That would be a binary or higher system.
6. Must not be in interstellar space, not associated with a sun or suns.
7. Not in a field of other bodies with the same approximate orbit. That would leave out anything in the Asteroid Belt and Oort Cloud.


Now, how about "Xena" (aka, 2003 UB313)? To Hades (Greek God of the underworld) with conventions for naming planets. Xena is perfect. And Gabrielle for the moon.

Answer 4

I understand why some people think it shouldn't be, but I have a sentimental attachment to Pluto. It was discovered in my home state!

In any case, no point in taking it away now. The definition is completely arbitrary anyway. The more, the merrier!

And in response to SPLATT, speaking of Hades, Pluto is an alternate name for the God of the Underworld. That's why the 11 year old who suggested Pluto as the planet's name when it was discovered in 1930.

Answer 5

I think maybe we should find a bigger one to take it's place first. Pluto is smaller than our moon. Part of the problem recently is the discover of so many other planets like Pluto circling the sun that we could have 50 planets if Pluto is one also.

Answer 6

I think that if Pluto has enough gravity to keep it spherical then that sets it apart from a comet,meteor, asteroid that is irregularly shaped.I say this becasue it is a Keiper belt object that was pulled into the Suns gravitational field.
It orbits the sun and also has a moon in orbit around it which further constitutes its specification as a planet.
Pluto is the little brother of our solar system, leave Pluto alone.

Answer 7

If I got to vote on it, my vote would be YES...purely for romantic reasons and historical context. Of course, 500 years from now when we have discovered dozens or even hundreds of similarly-sized Kuiper Belt Objects, historical context will have a different perspective.

Oh yeah...I think it'd be great to define all Kuiper Belt Objects that are spherical as planets. The only reason would be to mess with those silly astrologers. Of course, if Pluto is demoted from planet status, it's still going to be fun watching them squirm. It's funny, there are at least 6 moons of the solar system that are larger than Pluto...but astrologers never mention if Ganymede was rising when I was born. Surely it's influence is greater than Pluto's.

Answer 8

I never did think Pluto was a planet in the traditional sense: too far out, too small, too many questions about its origins. So I can take it or leave it as it is. But look, at this language and definition stuff again. See what I mean. We cant decide this until we have decided that - to properly define planet for goodness sake - you mean we have'nt!? Still?! Or is it that we are updating our definition?

Answer 9

Yes because then we would not have the pies that my very excellent mother just served us nine of. Just kidding. Its seems like there will no longer be nine planets after the International Astronomical Union conference in august. Who knows if 2003 UB313 will become a planet. The first thing is for them to properly define planet and then I guess decide from there.

Answer 10

I think yes because i've grown up with Pluto as a planet and it should stay that way. I don't see why they have to say that it's not a planet, it's definitely big enough and it's definitely not a moon because it's not orbiting any planets. It needs to stay classified as a planet.