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Analysis Suggests Solar System Contains Massive Trans-Neptunian Objects
BarbaraHudson writes NBC News reports that at least two planets larger than Earth likely lurk far beyond Pluto, just waiting to be discovered, a new analysis of the orbits of "extreme trans-Neptunian objects" (ETNOs) suggests. The potential undiscovered worlds would be more massive than Earth and would lie about 200 AU or more from the sun — so far away that they'd be very difficult, if not impossible, to spot with current instruments. "The exact number is uncertain, given that the data that we have is limited, but our calculations suggest that there are at least two planets, and probably more, within the confines of our solar system," lead author Carlos de la Fuente Marcos, of the Complutense University of Madrid, said. (Here's the longer version at Space.com.)
are your protuberances a little bit perturbed?
I wonder what they're going to call these new objects, because they'll probably find a reason not to call them planets just like they did for Pluto.
They're too big to be dwarf planets... Maybe elf planets?
Perhaps KP's, Kuiper Planets. Which could start a whole new Planetary naming system based on regional distance from a star instead of what we have now. Everything round + blah between the Star and it's local Kuiper Belt type region would be either an Inner Planet or Solar Planet, everything otherwise fitting that definition but within the Kuiper Belt would be a Kuiper Planet and anything further than that would be an Oort Planet.
That might even allow Pluto to be reclassified as a planet again, either a Solar Planet or Kuiper Planet. I really think this system, plus other basic details like roundness etc, could be a more useful system. It would also allow a way to keep the number of planets more manageable since we could mostly focus on the Inner/Solar Planet count for general public use without the number of them being too high to manage.
New Planet types based on Region/Distance from star:
Inner Planet or Solar Planet
Kuiper Planet
Oort Planet
btw: I made a post as anon under the same parent post before this, then thought I should log in and elaborate. The previous post was:
" They'll probably be called KP's. Kuiper Planets."
I don't think orbital dynamics has ever been used to discover an asteroid or comet or trans-Neptunian object. Certainly it's used to confirm their orbits (I've done that myself, freezing my ass off overnight taking a glass photographic plate, then measuring how much a small dot moved night to night). But asteroids have too little mass to to appreciably change the orbits of the larger planets. Ceres (along with a lot of other asteroids in the asteroid belt) in particular was discovered by blind luck by people searching almost at random for another planet between Mars and Jupiter. So to for that matter was Pluto - people were chasing what turned out to be an error in Neptune's calculated mass, and Pluto just happened to be near the spot that error predicted at the time they were looking.
Comets are discovered by (obsessed) people scanning the sky every night for a fuzzy dot that shouldn't be there. It's actually the same process as for asteroids (except now you have a computer do the observation instead of freezing your ass off like I did), and if the orbital calculations say it's a highly elliptical orbit instead of circular, you have a comet. The gas jets from vaporizing material as they approach the sun (which gives them their "tail) are pointed in random directions, and perturbs their orbit enough to make precise orbital calculations useless. Only general calculations like Halley's Comet returning every 86 years work.
Orbital calculations work well for (A) objects which are relatively close together since gravity decreases as the inverse square of distance, and (B) have relatively short orbital periods since this means they move faster and thus generate a larger measurable motion against the background stars. Neither of these hold true for trans-Neptunan objects.
If you subscribe to the theory that the solar system started out as a cloud of matter, and a slightly larger lump somewhere happened to coalesce into the sun by gravity, then it makes sense that the further you go out, the more material there is simply because of geometry. The volume of space (restricted to near the plane of the solar system) goes up as the square of the distance from the sun. While the length of the orbit only goes up proportional to the radius. So there must be more stuff in the outer solar system than in the inner. It's just spread out more.