we already have a 9'th planet, but due to the greatest pedantic campain of all time, pluto got demoted. Though given the current situation, ha!, that could change.....perhaps the naming commity will get noticed, and be offered a chance to do a deal, and Make Pluto A Planet Again,(MPAPA)
We should add those planets to the official list too. Gauss considered Ceres to be a planet and I believe him over living astronomers.
The motivation for this dwarf planet nonsense was to try to keep the official planet list small so children could memorize them with ease, but that is absurd. We do not remove countries from the map to make it easier for children to learn geography and there are over 100 of them.
For a generation, schoolchildren everywhere memorized the names of the 12 planets: Mercury, Venus, Earth, Ceres, Pallas, Vesta, Juno, Mars, Jupiter, Saturn, Uranus, and Neptune.
The list was stable at 12 for about 40 years, but started growing again in the middle of the century. By 1868 there were 100 named asteroids. Not a single one has people living on it, so making children memorize their names was seen as a waste of time. Teach them about the asteroid belt and then move on to more important things. Likewise with the TNO: teach them about the Kuiper belt and the Oort cloud and then move on to more important things. No need to make them memorize Pluto, Haumea, Makemake, Gonggong, Quaoar, Sedna, and Orcus, nor any of the hundreds of other named TNO.
Can anyone justify why children should be required to learn about anything outside of our atmosphere beyond the sun and moon at school? It is trivia with no practical applications. It is not logical to design classification schemes for ultimately useless knowledge based on the learning ability of children.
Remelting whole planet is such a nonsense, it would take millions of years for the large body as Mars to cool enough for surface to be usable.
By the way, the loss of atmosphere takes millions of years too. The popular "we must restart mars magnetic field" trope likes to omit the fact. In the end occassional replenishment of volatiles would probably be cheaper.
If planets are required to clear their orbits, what was Jupiter called while the solar system was forming? A dwarf planet? A proto planet? The entire time?
Was earth not a planet shortly before and after collision with Theia?
The naming pedantry seems ridiculous given that we have such a small sample size.
Every single definition that segments a real world set of continuous objects into discrete buckets has surprising edge cases. This is basically inescapable.
To steal a quote: All definitions are wrong. Some are useful.
I find that to be the most weird one too. I don't know much about orbital mechanics but in the unlikely chance 2 bodies shared an orbit does that mean they aren't planets then? How close can two planets be before losing that designation? I share your ire.
> If planets are required to clear their orbits, what was Jupiter called while the solar system was forming?
Hell, what's it called now? Jupiter's orbit is shared with millions of Trojans. Many of them are more than a hundred kilometers in diameter; for reference, Deimos, one of Mars' moons, has a mean radius of about 6 km.
Back in the day Mercury, Venus, Earth, Ceres, Pallas, Vesta, Juno, Mars, Jupiter, Saturn, Uranus, and Neptune were the 12 planets. You could kinda consider Pluto to be the 13th planet, but in 1930 when it was discovered there were already over 1000 named asteroids. So Pluto is the 1146th planet.
Pallas and Vesta aren't gravitationally rounded, though. But then again, the Moon is (being much larger than Ceres). (It's just better numbered as planet 3-1.)
The definition is pretty arbitrary. It's more interesting, what can we learn by studying that object. Even the trivia, like tidal locking, it was one of my 10000 moments (https://xkcd.com/1053/).
