Should Pluto be reinstated as a planet?

[freeztar]

This reminds me of Botanical explorations into nomenclature.
When does a flower become another species? How should we group them? etc.
We can now do DNA testing easily, but is it the end all be all?
What about phenology and phylogeny?

When is an iceball considered a planet? It has eccentric orbit and is way way far away from the sun, yet it orbits the sun. Perhaps we might call it a "regular collective comet". Seems more fitting.

I pseudo-vote no. I'm withholding my actual vote for any swaying arguments that may come.

[Southtown]

Moon stated my case better than I did. Why is a 'dwarf planet' not considered a 'planet?'

[Boerseun]

I just read an article about a suicidal Jupiter-sized planet that orbits its star in less than one Earth day. It creates massive tidal plasma bulges on both the planet and the star, and is expected to finally commit suicide by plunging into its sun in the next million years by its decaying orbit.

The more we learn from planets in other solar systems, the less it seems as if our layout is the norm.

Rocky planets, apparently, don't always develop in the inside track of the planetary plane, and giants not necessarily on the outside.

When we want to create a planetary taxonomy that would apply to all stars and planet systems in the galaxy, then all bets are off.

I'm sure our planetary system is about as odd and freakish to any other civilization out there, as theirs would be to ours.

I'm of the opinion that if Kepler can determine its orbit, then its a planet. They just vary greatly in size and composition.

If you think about it, if a paperclip is orbiting the sun in a straight-forward Keplerian orbit, it clearly is not a planet. But keep on adding paperclips until you have a ball of paperclips the size and density of the Earth. That would definitely be a planet. But between adding which two paperclips did it progress from being an orbiting "ball of paperclips" to being a bona-fide "planet"?

[Southtown]

Originally Posted by freeztar

Do you know when it's supposed to get to Pluto? It looks like it is almost to Uranus' orbit.

July 2015. I just watched a Naked Science: Pluto Rediscovered on hulu.

Hulu - Naked Science: Pluto Rediscovered - Watch...

[Pyrotex]

...Clyde Tombaugh, who discovered the planet-now-dwarf-planet, was born in Illinois.
...Meanwhile, New Mexico's House of Representatives proclaimed February 18, 2009, as "Pluto is a Planet in New Mexico Day" and praised Tombaugh, who worked in the state for decades and died there in 1997.

I had the distinct pleasure of meeting Clyde Tombaugh back in about 1990 or 1991.

It was in Houston, Texas, at the McDonnell Douglas building, near the NASA Johnson Space Center.
I was working on the Space Station Freedom project, and Clyde was invited to "bless" our efforts. He sat through several briefings, including one that I gave on the science that we were planning to do from the space station.
Somewhere, I have a picture of me shaking hands with Clyde.
He was a very patient and gracious guest. I'm sure he had to put up with a lot of silliness that day.

Did you know that Clyde was good friends with the science fiction writer, Robert A Heinlein?
Yes, indeed they were. In fact, in his short stories and novels, Robert often named the first or the biggest colony on the Moon, "Tombaugh Station".

I'll try to find that picture.

[DougF]

I think a 'dwarf planet' should be considered a 'planet?'
I Voted Yes!

[modest]

Originally Posted by Boerseun

If you think about it, if a paperclip is orbiting the sun in a straight-forward Keplerian orbit, it clearly is not a planet. But keep on adding paperclips until you have a ball of paperclips the size and density of the Earth. That would definitely be a planet. But between adding which two paperclips did it progress from being an orbiting "ball of paperclips" to being a bona-fide "planet"?

I think what you say there is key.

Whatever definition we give "planet", it needs to be well-enough defined to answer the above question. The current definition given by the IAU would say that it becomes a planet when it is capable of clearing the neighborhood around its orbit. I'm ok with that, but those voting yes should probably have some other determining factor for when a ball of paperclips become a planet.

I'm not sure how well it would work to say that anything being rounded by its own gravity would qualify. There are currently 70 such candidates and the list is estimated to expand to approximately 2,000.

List of dwarf planet candidates - Wikipedia, the free encyclopedia

I wouldn't want there to be 2,000 planets, so if Pluto is to be a planet then I'd think we need some way of setting a cutoff such that the number of planets could realistically be no greater than a few dozen even as we make new discoveries.

Any ideas?

Then again, maybe the people voting yes are not troubled by the prospect of a few thousand planets...

~modest

[Southtown]

I have no qualms with 2k planets. Whatever meets a certain definition, knowhatimean?

"Although the EC's original proposal seems simple and based on physical concepts (a planet is massive enough to be rounded by its gravity, orbits a star, and is neither a star nor a satellite of a planet), the definition stirred controversy among the planetary community. The challenge: under the new definition, there could soon be dozens of new 'planets' in our solar system. That struck many astronomers as the wrong result." – SPACE.com -- Planetary Definition Showdown! As Debate Rages, One Astronomer Says 'It's All About the Atmosphere'

[Moontanman]

I'm intrigued by the idea of being able to hold an atmosphere as a requirement for planetary status. this would mean that Pluto is a planet, as are many of the objects similar to Pluto via the low temperatures that far from the sun. By that definition Titan is also a planet. I think that for the most part people are looking for definitions that maintain the status quo of 9 planets.

[Southtown]

Originally Posted by Moontanman

By that definition Titan is also a planet.

Well also planets have to orbit stars, otherwise it's a moon. Ignoring that prerequisite would create all sorts of problems.