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Since it was stripped of planetary status, Pluto’s defenders have been fighting

theguardian.com

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Re: Since it was stripped of planetary status, Pluto’s defenders have been fighting

#61

Post by andrewflnr »

ivan_gammel wrote: post #31
adrian_b wrote: post #17

> “One of the biggest flaws with the IAU definition is that you can have the same object in two different orbits,” says Kornfeld. “In one, it’s considered a planet, and in the other, it’s not considered a planet.” No, there is no flaw in this, and moreover there is nothing new in this. This is how it has always been, it is not something invented recently. In the Solar System, there are 3 Mercury-sized satellites and…

I‘m seeing this classification for the first time, but it sounds very reasonable and feels like it should have been like that. Is it your idea or is there any story behind it?

We already have the terms "rocky planet" and "gas giant" that pretty much cover it. The only thing missing is an official IAU decision which, well, would have even less effect than the Pluto thing I'm guessing, since it would just be introducing a sub-division in the category.

Re: Since it was stripped of planetary status, Pluto’s defenders have been fighting

#62

Post by [deleted] »

drxzcl wrote: post #42
beloch wrote: post #28

Earlier quoted context omitted.

...or like saying Earth is not a planet because NEA's share our orbit. If you have to argue that it doesn't apply to Jupiter or Earth because they are obviously planets, it implies that "clearing the neighbourhood" is a vague and not particularly useful criteria.

Except I said nothing of the sort. I said the opposite. Jupiter, Neptune and earth in your example dominate the gravity of their orbit by locking the smaller bodies into orbital reasonances. It’s not a vague criterium. It might be an irrelevant one if you are interested in geophysics, but it’s concrete and testable.

[deleted]

Re: Since it was stripped of planetary status, Pluto’s defenders have been fighting

#63

Post by odyssey7 »

ketzu wrote: post #55
Planktonne wrote: post #30

The actual problem here is weirdly aggressive nerds who are incapable of nuance, and insist that an astronomical classification (Pluto is not a planet by the IAU definition) should be used in non-astronomical contexts. Historically and culturally, Pluto is considered a planet. An IAU classification shouldn't be used to try and retroactively change that, because the IAU does not have control over history and culture.…

I wonder how happy each group would be by this solution. Planet as a scientific and non-scientific usage. Conclusively, science class would not teach Pluto as a planet (it should after all stick to the science) and English class will discuss the cultural impact of planet Pluto! Maybe write poems about the importance and impact of 9 word mnemonics? Sounds fun. My headcanon is that people would hate it so so much! I ca…

This would be a really good discussion topic in schools.

People need to understand the dynamic between science and society, because that is an important part of how the world works today.

Pluto is an exemplar.

And also, the value of culture. It might not be a scientific result, but it still shapes our experience of the world. Pluto is beloved.

Re: Since it was stripped of planetary status, Pluto’s defenders have been fighting

#64

Post by vova_hn2 »

lenerdenator wrote: post #39
jsbisviewtiful wrote: post #21

In case anyone was curious, the Moon is bigger than Pluto. Pluto's 2/3 the size of the Moon. If any dwarf planet should be upgraded to a planet, it's Eris. Eris's diameter is over 600km bigger than Pluto's.

Aye, but what does Pluto orbit, and what does the Moon orbit?

Pluto orbits center of combined masses of itself and Charon, which does not lie within either of them. Also, they are both tidally locked to each other, just like Moon is tidally locked to Earth.

Re: Since it was stripped of planetary status, Pluto’s defenders have been fighting

#65

Post by vova_hn2 »

hn_submit wrote: post #45
space_fountain wrote: post #15

Earlier quoted context omitted.

The issue is that when we discovered Pluto we thought it was much bigger than it turned out to be. If it was as big as they thought then sure it would be a planet. As it is it isn’t even the most massive dwarf planet

They saw a problem with the discovery of other Kuiper Belt Objects and came up with a pseudo-scientific definition to "solve" the discrepancy.

> pseudo-scientific definition

How is it pseudo-scientific?

Re: Since it was stripped of planetary status, Pluto’s defenders have been fighting

#66

Post by snapcaster »

wolrah wrote: post #36
snapcaster wrote: post #16

Earlier quoted context omitted.

no you don't. just because some nerds say it doesn't make it true. just bring back pluto and nothing else

Science works on logical rules. What logical rule would you propose that allows Pluto to be a planet without also bringing in a bunch of others? If you just want to arbitrarily declare things are they way you like them to be, religion is over there.

>What logical rule would you propose that allows Pluto to be a planet without also bringing in a bunch of others?

The rule would be: pluto is a planet, stay mad nerds

Re: Since it was stripped of planetary status, Pluto’s defenders have been fighting

#67

Post by vova_hn2 »

hn_submit wrote: post #51
Avshalom wrote: post #27

Earlier quoted context omitted.

I'm on team Pluto here but no, the problem was that Mike Brown found like a dozen 'planets' and no one wanted to deal with that. It was closer to preventing someone from making a name for themselves.

We could simply define Pluto as the edge of our Solar System and everything beyond its orbit a Kuiper Belt Object. There's nothing wrong with that. Why bother coming up with a pseudo-scientific requirements list for planets when these don't work for a large number of cases.

> We could simply define Pluto as the edge of our Solar System and everything beyond its orbit a Kuiper Belt Object.

A Kuiper Belt Object not being a part of Solar System doesn't make any sense. A star system is the star + all objects that orbit it. Why would you arbitrarily exclude some objects that orbit the Sun?

Re: Since it was stripped of planetary status, Pluto’s defenders have been fighting

#68

Post by odyssey7 »

hn_submit wrote: post #9

I'm in the same camp. I believe the classification of Pluto as a dwarf planet was arbitrary and inconsistent. I mean, it's been known as a planet for almost 80 years and suddenly we demote it? I believe someone was trying to make a name for themselves here and ignoring the history of Pluto and its discovery.

> someone was trying to make a name for themselves

100%

Scientists try to coin new terms all the time. It’s great for the researcher if people actually use it. But why do that when you can just sign your name on a term everyone already uses?

Redefining “planet,” from the 9 culturally accepted symbols into something else, was a swindle. “Things that clear their orbits” could have been TTCTOs. It happens all the time, coining precise terms for things. Why should this one have been any different? The public was right to push back and to protect their mythology.

Re: Since it was stripped of planetary status, Pluto’s defenders have been fighting

#69

Post by ivan_gammel »

andrewflnr wrote: post #61
ivan_gammel wrote: post #31

Earlier quoted context omitted.

I‘m seeing this classification for the first time, but it sounds very reasonable and feels like it should have been like that. Is it your idea or is there any story behind it?

We already have the terms "rocky planet" and "gas giant" that pretty much cover it. The only thing missing is an official IAU decision which, well, would have even less effect than the Pluto thing I'm guessing, since it would just be introducing a sub-division in the category.

Oh, right. It does exist, it is very accurate, but the names sound like LOTR party:

- a gang of dwarfs

- some rocky ones

- and gas giants

- and one star to rule them all

Re: Since it was stripped of planetary status, Pluto’s defenders have been fighting

#70

Post by hn_submit »

bryanlarsen wrote: post #58
hn_submit wrote: post #51

Earlier quoted context omitted.

We could simply define Pluto as the edge of our Solar System and everything beyond its orbit a Kuiper Belt Object. There's nothing wrong with that. Why bother coming up with a pseudo-scientific requirements list for planets when these don't work for a large number of cases.

That would include Ceres, Quaoar and Orcus as planets. It's really hard to come up with a definition of a planet that includes Pluto but doesn't include Orcus. Orcus is very close to a mirror of Pluto that is 120 degrees out of phase. Even in name: Orcus is the Roman name for the Greek god Pluto.

What part of "we define it so" did you not understand?!
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