Do the Trojan asteroid clusters in Jupiter’s L4 and L5 points still count as “clearing its orbit”?
What if there were a second planet-sized body there?
I would say in that example:
Jupiter is the dominant mass making it be the planet.
Anything in the Lagrangian points would not be planets specifically because anything in those points are there because of Jupiter and its orbit, not in spite of it.
Clearing the orbit is a very shorthand version of the meaning. If it was literal, nothing could be a planet as there’s always something in every orbital path. It means the planet is massive enough to be the dominant thing within its orbit.
Mercury is an interesting case. While there are some moons that are larger than it, they aren’t nearly as dense. Its surface gravity is only a little less than Mars, even though its smaller in size, so it has potential for orbital domination. The Sun certainly helps in keeping other objects clear, but that shouldn’t be part of the equation, if Mercury qualifies as a planet it should be able to do it in any orbit. I wonder if you put Mercury where Ceres is and ran for a few millennia what would happen?
Do the Trojan asteroid clusters in Jupiter’s L4 and L5 points still count as “clearing its orbit”?
What if there were a second planet-sized body there?
I would say in that example:
There are mathematical formulae for defining it and the dwarf planets have orders of magnitude lower values in comparison to planets: https://en.wikipedia.org/wiki/Clearing_the_neighbourhood
Clearing the orbit is a very shorthand version of the meaning. If it was literal, nothing could be a planet as there’s always something in every orbital path. It means the planet is massive enough to be the dominant thing within its orbit.
Mercury: sweats
Mercury is an interesting case. While there are some moons that are larger than it, they aren’t nearly as dense. Its surface gravity is only a little less than Mars, even though its smaller in size, so it has potential for orbital domination. The Sun certainly helps in keeping other objects clear, but that shouldn’t be part of the equation, if Mercury qualifies as a planet it should be able to do it in any orbit. I wonder if you put Mercury where Ceres is and ran for a few millennia what would happen?
Everything sweats (or boils) that close to the sun.