I imagine nasa would be perfectly fine with Pluto still categorized as a planet. It was just a handful of people at a IAU conference(many had left by the time the vote happened) that made the change.
Historically it’s fine. Technically it’s not. The thing is, it’s still a type of planet, it’s not like it’s now called something completely different. It’s more specific to fall in line with the likely many, many neighbors that are out there.
I would completely agree with you except IAU specifically said Pluto is a dwarf planet and that, for some reason, a “dwarf planet” is NOT a sub category of planet. It’s its own thing and not a planet.
It was a weird conference and a weird vote.
Edit: “planet” IMHO is more of a traditional category like constellation. Some how a tiny rock like mercury is more like Jupiter than the tiny rock Pluto. It doesn’t make much scientific senseso it seems more traditional. It would be like removing the name for a constellation because one of the stars is really a bright nebula or something.
Nah, the other option was to add a bunch of planets, including Ceres right between Mars and Jupiter. If you wanted to keep things as close to what they were before, removing Pluto was the more conservative option.
There could be many options. My favorite is a reclassification. Terrestrial planets(first 4), gas planets (next 4) and drwarf planets (numerous). Though mercury could fit into the dwarf planet category which is fine with me. The current classification was made specifically to demote pluto with rules that particularly apply to it so that mercury would not fit into it. It was to keep the “planet” category special and to not have too many(keep it traditional). Seems a bit geocentric and less scientific.
The problem is that since Pluto was discovered, we’ve found many similar bodies. Astronomers suggest there could be hundreds.
If you define “planet” so that it excludes Pluto, 8 objects in our solar system qualify as planets. Any definition that includes Pluto qualifies at least 13 planets with a high likelihood that that number will increase every few years.
It is convenient to classify it as a dwarf planet but that doesn’t mean that “dwarf planet” and “planet” are scientific categories in the purest sense of the term
What’s the “purest sense of the term”? A planet is presently defined as a body which orbits a star, has enough mass to be roughly round, and has cleared its orbit of other objects. Dwarf planets are defined as fulfilling the first two criteria, but not the third.
I mean that these descriptions are somewhat arbitrary. Roughly round is not a very precise delineation, there will be edge cases where it’s not clear which category they fall into
The actual qualification is “hydrostatic equilibrium”, but I didn’t want to complicate the point with technical mathematical jargon.
there will be edge cases where it’s not clear which category they fall into
Which is pretty par for the course so far as scientific classifications go. Classification is a human endeavor to attempt to neatly categorize things to better understand them, but the universe is what it is and defies tidy categorization. Just about any scientific classification you can devise will have edge cases and ambiguity.
Which is pretty par for the course so far as scientific classifications go.
Well yes I don’t necessarily disagree with you there. But there are some cases where it’s more obvious than others. A good example would be ring species: https://en.wikipedia.org/wiki/Ring_species
I’d say planets are about the same level of arbitrariness as far as scientific categories go
Yes, the vote was held at the end of the final day of the two-week IAU conference, when fewer than 500 of the 2500 attendees were still there. This scheduling was almost certainly a deliberate move to take advantage of the predictably low number of members who would still be present.
I can buy that but it leads to an interesting question…
If it was deliberate, why? To what purpose? Is there a cabal or cult or even one thought leader who was on the committee that had strong enough opinions on this, enough to scheme.
Maybe a kid who, in school, got a question wrong about Pluto and was made fun of. Looked it up afterwards, rationalized his answer instead of accepting they were wrong in forgetting, Vowed to get revenge. Studied and progressed to get on the committee and slowly over the years, schemed to engineer this. I hope they slept soundly that night.
To what purpose? To get the outcome they wanted. If they personally knew a lot of people who favored declassifying Pluto as a planet, and could encourage them to stay until the very end - maybe schedule a great party that night, I dunno. They could also make a point of shmoozing attendees who had rooms until the last night, spreading talking points. I mean if congresspeople use this tactic, why not astronomers?
I imagine nasa would be perfectly fine with Pluto still categorized as a planet. It was just a handful of people at a IAU conference(many had left by the time the vote happened) that made the change.
Historically it’s fine. Technically it’s not. The thing is, it’s still a type of planet, it’s not like it’s now called something completely different. It’s more specific to fall in line with the likely many, many neighbors that are out there.
I would completely agree with you except IAU specifically said Pluto is a dwarf planet and that, for some reason, a “dwarf planet” is NOT a sub category of planet. It’s its own thing and not a planet.
It was a weird conference and a weird vote.
Edit: “planet” IMHO is more of a traditional category like constellation. Some how a tiny rock like mercury is more like Jupiter than the tiny rock Pluto. It doesn’t make much scientific senseso it seems more traditional. It would be like removing the name for a constellation because one of the stars is really a bright nebula or something.
Nah, the other option was to add a bunch of planets, including Ceres right between Mars and Jupiter. If you wanted to keep things as close to what they were before, removing Pluto was the more conservative option.
Who said the goal was to keep things as they were?
There’s no reason not to add Ceres, or even the Moon, really.
There could be many options. My favorite is a reclassification. Terrestrial planets(first 4), gas planets (next 4) and drwarf planets (numerous). Though mercury could fit into the dwarf planet category which is fine with me. The current classification was made specifically to demote pluto with rules that particularly apply to it so that mercury would not fit into it. It was to keep the “planet” category special and to not have too many(keep it traditional). Seems a bit geocentric and less scientific.
I totally agree. It felt like it was an arbitrary ruling to keep the number of memorable celestial bodies low.
I actually like the idea of PMOs being defined as planets but it also sounds like there’s too much disagreement for any resolutions on this topic.
The problem is that since Pluto was discovered, we’ve found many similar bodies. Astronomers suggest there could be hundreds.
If you define “planet” so that it excludes Pluto, 8 objects in our solar system qualify as planets. Any definition that includes Pluto qualifies at least 13 planets with a high likelihood that that number will increase every few years.
What’s the problem with there being hundreds of planets? We have no issues with there being thousands of mammals.
It is convenient to classify it as a dwarf planet but that doesn’t mean that “dwarf planet” and “planet” are scientific categories in the purest sense of the term
What’s the “purest sense of the term”? A planet is presently defined as a body which orbits a star, has enough mass to be roughly round, and has cleared its orbit of other objects. Dwarf planets are defined as fulfilling the first two criteria, but not the third.
Define “clear”. Define “neighbourbood” (which is the term in the definition).
Do it in a way that doesn’t change the body’s definition if you physically move it to a new location, say to another star system.
Sounds like you want to consult the literature on the matter.
I mean that these descriptions are somewhat arbitrary. Roughly round is not a very precise delineation, there will be edge cases where it’s not clear which category they fall into
The actual qualification is “hydrostatic equilibrium”, but I didn’t want to complicate the point with technical mathematical jargon.
Which is pretty par for the course so far as scientific classifications go. Classification is a human endeavor to attempt to neatly categorize things to better understand them, but the universe is what it is and defies tidy categorization. Just about any scientific classification you can devise will have edge cases and ambiguity.
Well yes I don’t necessarily disagree with you there. But there are some cases where it’s more obvious than others. A good example would be ring species: https://en.wikipedia.org/wiki/Ring_species
I’d say planets are about the same level of arbitrariness as far as scientific categories go
Yes, the vote was held at the end of the final day of the two-week IAU conference, when fewer than 500 of the 2500 attendees were still there. This scheduling was almost certainly a deliberate move to take advantage of the predictably low number of members who would still be present.
I can buy that but it leads to an interesting question…
If it was deliberate, why? To what purpose? Is there a cabal or cult or even one thought leader who was on the committee that had strong enough opinions on this, enough to scheme.
Maybe a kid who, in school, got a question wrong about Pluto and was made fun of. Looked it up afterwards, rationalized his answer instead of accepting they were wrong in forgetting, Vowed to get revenge. Studied and progressed to get on the committee and slowly over the years, schemed to engineer this. I hope they slept soundly that night.
To what purpose? To get the outcome they wanted. If they personally knew a lot of people who favored declassifying Pluto as a planet, and could encourage them to stay until the very end - maybe schedule a great party that night, I dunno. They could also make a point of shmoozing attendees who had rooms until the last night, spreading talking points. I mean if congresspeople use this tactic, why not astronomers?