Newly proposed definition of "a planet" still excludes Pluto

[boingboing]

Originally published at: https://boingboing.net/2024/07/20/newly-proposed-definition-of-a-planet-still-excludes-pluto.html

…

[newbrain]

@boingboing

(a) orbits one or more stars, brown dwarfs, or stellar remnants;
(b) is more massive than 1023 kg; and
(c) is less massive than 13 Jupiter masses (2.5 × 1028 kg).

So my KIA car qualifies! Great!
(a) it’s on Earth, so it orbits our sun.
(b) weighs more than 1.023 tons.
(c) weighs less than 33.41 2.57 tons.

I think a superscript got somehow lost during shipment, should have been (unicode):

(a) orbits one or more stars, brown dwarfs, or stellar remnants;
(b) is more massive than 10²³ kg; and
(c) is less massive than 13 Jupiter masses (2.5 × 10²⁸ kg).

Or (< sup>< /sup>):

(a) orbits one or more stars, brown dwarfs, or stellar remnants;
(b) is more massive than 10²³ kg; and
(c) is less massive than 13 Jupiter masses (2.5 × 10²⁸ kg).

@boingboing

trans-Neptunian objects

Could be gadgets from a nastier version of “Rocky Horror Show”…

Edit: corrected upper weight limit, thought Jupiter mass was 2.5×10²⁸ (car still qualifies! Yay!).

[mick129]

From Gail Sherman.

The 2006 rule actually said “orbits the Sun”?! That feels like wording from another century.

[danimagoo]

Thank you. I was confused. By the definition in the post, a blue whale is too large to be considered a planet.

[gatto]

what about a bowl of petunias?

[anon59592690]

Again!?

[llamaspit]

This whole kerfuffle around the planetary status of Pluto seems to illustrate the very human tendency to resist change. So many people remembered the 9 planet thing from elementary school that it became an object of faith. If there are only 8 actual planets, what other knowledge from my childhood will turn out to be revised? Is anything real? Is anything permanent?

Secondarily, it also illustrates that some humans will get their panties in a twist over things that come nowhere near impacting their own lives. What actual difference does it make if science revises the definition of a planet? None difference is the answer.

[danimagoo]

The 9 planet solar system we were taught in elementary school is gone regardless of what definition you want to use of a planet. If we use a definition that includes Pluto, then we’re probably going to have to add at least 8 other planets to our solar system. So you’re right, people just resist change. But in this case, change was inevitable. Either we get fewer planets, and a new classification of dwarf planets, or we get a lot more planets. Sticking with the 9 was never an option.

[simonize]

Kind of like how the asteroids were originally classified as planets.
I’m picturing a cartoon where Ceres is consoling Pluto…
“That’s alright, I used to be a planet too…”

[FGD135]

@newbrain

So my KIA car qualifies!

But has it cleared the neighborhood?

[danimagoo]

insert joke about going through the drive-thru at Chipotle

[blackanvil]

So what do you call a rocky body greater than 10²³ kg and less than 13 Jupiter masses that, like Oumuamua, is just passing through the solar system, hopefully without a fender bender on the way?

[lorcan_nagle]

There’s a Star Trek novel in which a massive Borg Cube is approaching Earth and it consumes Pluto on the way in to gain even more mass. As it happens Admirals Jellico and Shelby note that for the last almost four centuries scientists have been arguing back and forth about whether Pluto was a planet or not, but now it’s immaterial

[anon73430903]

@llamaspit

So many people remembered the 9 planet thing from elementary school that it became an object of faith.

They were going to have to deal with change anyway. At the time the options were

1. There are eight planets
2. There are at least ten planets (Eris was thought to be slightly bigger than Pluto back then)

There was no option for “There are nine planets”

[bobsyeruncle666]

Well, I’m more than a little confused but… is there still hope for the Death Star and for round whales?

[smulder]

… maybe it would be easier to explain what Pluto is if we rename Neptune “Goofy”

[jimdoria]

I thought 1023kg seemed suspiciously light. But exponent formatting aside, the paper itself seems to say 10^21 kg.

[gatto]

@anon73430903

There was no option for “There are nine planets”

i’ve argued elsewhere that they could have created a new term such as “standard planet” for the scientific definition. this would have allowed everyone to continue to use “planet” loosely, and would keep sol’s non-standard planets at nine

this would even have had the advantage of easily distinguishing which definition is meant when looking at scientific papers. older papers aren’t going to be rewritten to accommodate the new definition, so “planet” will continue to be an indication of a general idea in a large swath of scientific literature anyway

“standard planet” ( or some other term ) would have made it clear what a person or paper means when referring to an orbital body.

[jerwin]

The “excludes exoplanets” was an entirely avoidable criterion.

[jerwin]

The IAU gives official names to major planets. The IAU does not have to convene a committee if it’s a minor planet. So the prospect of several dozen new planets beyond neptune might have entailed a bit more bureaucracy that the IAU was willing to shirk.