New planets... and plutons

[Fredrik]

Details about the upcoming revised definition of "planet" have finally been published. Parts of the proposal are a bit surprising (plutons?), but I think it sounds logical. In any case, I, for one, welcome our new planetary overlords.

[Sharessa]

Hey that's pretty cool. I've always thought it would be awesome to see new planets discovered, and while that's not technically what's happening these are likely going to be added to the lists that grade school kids learn which is just as cool. Isn't Charon Pluto's moon?

[Doom_Dude]

Sounds fine by me. I'm glad that Pluto isn't going to be demoted from being classified as a planet.

[Nautilus]

Danarchy said:

Isn't Charon Pluto's moon?

Yes. Speaking of which, a couple of possible "moons" of Pluto were spotted. http://news.bbc.co.uk/1/hi/sci/tech/4396546.stm

[Fredrik]

By the way: this will upset astrologers.

[Little Faith]

Fredrik said:

By the way: this will upset astrologers.

...which would not be too bad a thing.

It's nice to see Ceres getting her planet status back.

By the way, what do you think 2003 UB313's official name will be?

It is supposed to be named after some sort of creation diety from what I hear.

Ymir or Tiamat could be cool.

[Snarboo]

Danarchy said:

Isn't Charon Pluto's moon?

Yes, but Pluto and Charon are pretty similar in size and orbit around a shared center of gravity, so I guess they consider it a binary planet.

This is pretty good news. I'm glad they were able to reach a decision on this. Plutons is a pretty good description of what Kuiper Belt objects are.

[CODOR]

Fredrik said:
By the way: this will upset astrologers.

Are plutons planets? Easy solution: make two sets of astrological predictions of the near future, one accounting for the plutons, and one assuming that the solar system has just 8 planets. Whichever one comes closest to what actually happens wins.

[Grazza]

I suppose the logic with Pluto and Charon is that the centre of rotation is not within either object. This would be the basis on which Earth's moon is not considered a planet. Edit: yes, confirmed by footnote 2 to the draft resolution.

[Lüt]

Little Faith said:

Ymir or Tiamat could be cool.

I would've said Tiamat 3 albums ago but everything since Skeleton Skeletron has been mediocre at best. Not that the first 3 were great either, but they were really on to something with Wildhoney and A Deeper Kind Of Slumber, and then... somebody held the rope and took the fall :(

[Sharessa]

Tiamat is the 5-headed dragon goddess from D&D, noob.

Fredrik said:

By the way: this will upset astrologers.

Good, their stuff has been BS from day one anyway.

Old Carnifex Avatar Guy said:

By the way, what do you think 2003 UB313's official name will be?

Persephone! Seriously, it's a really cool name that a lot of sci-fi authors have used for the "10th planet" and it fits in with the Greco-Roman gods thing. If I ever have a daughter, I'm going to name her Persephone. It's such a pretty name.

[Ichor]

Little Faith said:

By the way, what do you think 2003 UB313's official name will be?

Death Star

[CODOR]

Ichor said:
Death Star

Too late, Mimas already got that one...

[Technician]

Damit. Now we have more planets to memorize. It’s like adding more reindeer to the song or letters to the alphabet. It’s strange and confusing and has me scared. When will the insanity end?

[Snarboo]

Little Faith said:

Ymir or Tiamat could be cool.

The name Ymir is already given to one of Saturn's moons.

[Gokuma]

Marduk, slayer of Tiamat!

[ducon]

Fredrik said:

By the way: this will upset astrologers.

They won’t change their opinion. They survived Uranus, Neptune and Pluto.

Danarchy said:

Tiamat is the 5-headed dragon goddess from D&D, noob.

Tiamat existed before D&D, n3wB.

[AirRaid]

http://www.reallifecomics.com/archive/060817.html

Heh.

[david_a]

ducon said:

They won't change their opinion. They survived Uranus, Neptune and Pluto.

Yup. Those people will overcome trivialities like a change in the number of planets easily if it means staying in business.

[myk]

Little Faith said:
Tiamat could be cool.

Tiamat is dead!

[Donce]

The term plutons would be quite a good replacement for KBOs. Just, in my language, Pluto and pluton would be exactly the same word, so Pluto could be distinguished only by the first capital letter :)

And as for the question "are plutons planets", I understand that the answer would be - some. Those few who meet the criterium of a round body. Just like there's one asteroid - Ceres - which also meets it.

That said, I would prefer leaving the nine classical planets (or, if there's a need to change that number, rather remove Pluto from them, cause then I could say I've seen all the planets, but now I can't :P)

[Sharessa]

ducon said:

Tiamat existed before D&D, n3wB.

Way to interpret sarcasm, nooblet.

[Grazza]

Donce said:

And as for the question "are plutons planets", I understand that the answer would be - some. Those few who meet the criterium of a round body.

Looking at the page Fredrik linked to (and the draft resolution itself), then all plutons by definition are planets - it describes them as a category of planetary objects.

[Donce]

Grazza said:

Looking at the page Fredrik linked to, if its summary of the draft resolution is precise, then all plutons by definition are planets - it describes plutons as a category of planets (those that take more than 200 years to orbit the sun).

Ah, right. So then plutons would be a third group of planets added, an addition to the inner planets and gas giant planets. Hmm, then plutons won't be a replacement for Kuiper Belt Objects, since majority of them aren't large enough.

[Grazza]

I don't know if you noticed that I had edited my post above. This was because I had seen that the draft resolution didn't seem utterly clear on what precisely defined a pluton. The one (fairly) clear thing is that they need to meet the new definition of a planet.

Whether the distance is a necessary and sufficient additional condition is not clear to me (the Q&A suggests it is; the draft resolution is less clear) - would a large outer planet with a regular orbit be called a pluton? And would a Ceres-sized/shaped object with an orbital period of 199 years not be called one?

[Sharessa]

Also, I might be reading stuff wrong, but it seems that Ceres would be labeled as a pluton as well. That doesn't make much sense considering it's more like an inner planet (though I have no idea how long its orbit is).

[Fredrik]

That's certainly not what they mean, but I agree that the punctuation there is ambiguous.

[Lobo]

Confusing for spanish people because Pluto is already called "Pluton" en español...

[Fredrik]

Same problem in French.

[Grazza]

Fredrik said:

That's certainly not what they mean, but I agree that the punctuation there is ambiguous.

It's clear what they're getting at (and that Ceres isn't one, whichever version of the statement you're looking at), but it isn't obvious if they have actually made a clear-cut definition, or if it will be a matter of debate on a case-by-case basis.