This discussion focuses on the peculiar orbit of Pluto and its classification as a planet. Participants highlight that Pluto's orbit is likely influenced by gravitational interactions with other outer planets and propose that it may be a captured Kuiper Belt object. The conversation also touches on the historical context of Pluto's discovery in 1930 and the subsequent identification of Charon as its moon. Additionally, the discussion raises questions about the orbital dynamics of other celestial bodies, such as Triton, which orbits Neptune in the opposite direction of its planet's rotation.
PREREQUISITESAstronomers, astrophysicists, educators, and students interested in planetary science and the dynamics of celestial bodies in our solar system.
Originally posted by MajinVegeta
Why isn't charon considred the planet, and pluto its moon? What's the current definition of a planet?
The biggere one is the planet.Why isn't charon considred the planet, and pluto its moon?
Although there is some possibility that Pluto may be an escaped movement of Neptune, or an object completely foreign to our solar system, I think it far more likely than that it is simply a very large Kuiper Belt object. The Kuiper Belt is an asteroid Belt just outside the orbit of Neptune that appears to mark the end of the planetary system, and the beginning of the Oort cloud, just as the inner asteroid Belt appears to mark the end of the Rocky planets and the beginning of the gas giants.Originally posted by Loren Booda
Pluto may be a body adopted by our solar system, orbiting in the sense of other solar bodies. What if Pluto had approached our system from the opposite direction - would it have been as likely to have been captured, or at all? What of comets, do they all orbit in the same sense as the planets?
One of the largest moons in the solar system, Triton, orbits Neptune in the opposite direction from all other satellite and planetary orbits. This gives rise to the conjecture that it, too may be a very large Kuiper Belt object. Only in this case, one that actually has gotten trapped into and orbit. Further evidence is the fact that this orbit is far more elliptical than any of the other satellites in the solar system, and that it is decaying. Eventually, Triton will pass too close to Neptune and get torn apart, adding to Neptune's already complex ring system. Almost makes one wonder if that is where all the material for Neptune's rings originally came from.How about around a given planet; are there any substantial moons that circle in opposition to each other, or to parent planetary rotation in general? When we send an artificial satellite around a body, does it orbit with, or against the natural satellites present?
In other words, what deviations are there for orbiting or rotating bodies in the Solar system from the preferred sense (Sun's?) of rotation? Neptune seems the odd god out.