But isn't that basically the opposite of the scientific method? "We can't change our definitions or categories if we learn new things! We have to keep describing things the way they used to be in...
Metzger and his co-authors argued that the third piece of that definition does not match historical usage by scientists and should be revoked.
But isn't that basically the opposite of the scientific method? "We can't change our definitions or categories if we learn new things! We have to keep describing things the way they used to be in the olden days!"
As the article hints, every moving object in the sky was originally classified as a planet, because the word originally comes from the Greek "planetes", meaning "wanderer". The Sun and the Moon were both originally one two of the seven planetes (along with Mercury, Venus, Mars, Jupiter, and Saturn). Should we not have reclassified them as we learned more about what they are, because that's how they were always described?
This has to be one of the silliest arguments for classifying Pluto as a planet that I've seen.
EDIT: The Sun and the Moon are two things, not one!
It says in Genesis that "God made two great lights: the greater light to rule the day, and the lesser light to rule the night". He made two great lights, not one! That's enough scientific proof...
Link to paper (only the abstract is publicly available) The argument they're putting forward seems reasonable to me - that the defining quality of a planet is whether it's big enough that gravity...
Link to paper (only the abstract is publicly available)
The argument they're putting forward seems reasonable to me - that the defining quality of a planet is whether it's big enough that gravity has turned it into a sphere, because that threshold also kicks off a lot of interesting geological processes. The question of whether it's big enough to have cleared the orbit of other objects is much less relevant.
However, it's not entirely irrelevant. We are allowed to have more categories than: not big enough to form a sphere; big enough to form a sphere, but not big enough to start fusion; big enough to...
The question of whether it's big enough to have cleared the orbit of other objects is much less relevant.
However, it's not entirely irrelevant. We are allowed to have more categories than:
not big enough to form a sphere;
big enough to form a sphere, but not big enough to start fusion;
big enough to form a sphere, and start fusion.
We already sub-categorise stars and planets: there are red giants and white dwarfs, there are gas giants and terrestrial planets, and many many more sub-categories. Why not have one more sub-category for a type of planet that isn't massive enough to clear its orbit?
We recommend that, regarding planetary taxonomy, central bodies such as the IAU do not resort
to voting to create the illusion of scientific consensus. The IAU has done damage to the public
perception of science, which is a process free from centrally dictated authority, in its imposition
of a definition of planet and the number of planets fitting that definition, which has been instilled
in educational textbooks around the world on the basis of their authority.
But isn't that basically the opposite of the scientific method? "We can't change our definitions or categories if we learn new things! We have to keep describing things the way they used to be in the olden days!"
As the article hints, every moving object in the sky was originally classified as a planet, because the word originally comes from the Greek "planetes", meaning "wanderer". The Sun and the Moon were both originally
onetwo of the seven planetes (along with Mercury, Venus, Mars, Jupiter, and Saturn). Should we not have reclassified them as we learned more about what they are, because that's how they were always described?This has to be one of the silliest arguments for classifying Pluto as a planet that I've seen.
EDIT: The Sun and the Moon are two things, not one!
I'm not buying it.
It says in Genesis that "God made two great lights: the greater light to rule the day, and the lesser light to rule the night". He made two great lights, not one! That's enough scientific proof for me. :)
And it still is a planet - it's a cute adorable little dwarf planet.
Poor thing is only around 60% the size of our moon.
They named an entire class of heavenly bodies after Pluto, but people still act like it got shafted!
Link to paper (only the abstract is publicly available)
The argument they're putting forward seems reasonable to me - that the defining quality of a planet is whether it's big enough that gravity has turned it into a sphere, because that threshold also kicks off a lot of interesting geological processes. The question of whether it's big enough to have cleared the orbit of other objects is much less relevant.
However, it's not entirely irrelevant. We are allowed to have more categories than:
not big enough to form a sphere;
big enough to form a sphere, but not big enough to start fusion;
big enough to form a sphere, and start fusion.
We already sub-categorise stars and planets: there are red giants and white dwarfs, there are gas giants and terrestrial planets, and many many more sub-categories. Why not have one more sub-category for a type of planet that isn't massive enough to clear its orbit?
The paper is on the arXiv:1805.04115.
What do you think about that claim?