Charon is a planet because it is NOT a moon, we thought it is, but its not!?

Question

pluto and chaorn orbits a point in space so if u say charon is the moon of pluto, then how about pluto is the moon of charon???

original defintion of planet is good and they only count up to 12 because later on , they will keep on adding more, so dont say original definition suck.

Answer 1

Well, I believe the Pluto-Charon pair is not planet-moon system, but a twin-planet system.

Think about it. If twin binary stars are possible, what's to prevent the formation of twin planets? It is very much possible.

Answer 2

Putting sentamentality aside, I am in favor of an 8-planet model for the Solar System.

Ceres would seem to be the largest object at its distance that had time to coalesce, consolidate and become spherical under its own gravity. I accede that that is significant - it is large enough to be round, but it is still an object in an asteroid belt.

As a binary system, the Pluto-Charon system is a significant TNO, or Pluton (as is the new definition) of the Kuiper Belt. It is clearly a member of this more diffuse band of objects in the outer Solar System.

Both Ceres and Pluto-Charon (and Xena) are significant representatives of their group, but still members of the group.

It can be argued that the terrestial planets are a group and the gas giants are a group, and that if you follow my point, then either only (Earth and Jupiter), or (Neither) are planets. But that is beside the point. These groups are small, and the planets are significant, and there are no other significant objects in their orbit.

On an related note, it's hard to think of Proxima Centauri as a part of the Alpha-Cen system. It is really a passing red dwarf that is weakly bound to the system. In time, with perturbation, it will either drift out of the gravity well, or fall into a tighter bond.

Answer 3

Yes! The definition of planet proposed and all in the news is a good idea! But charon is no planet. It is still a moon since it is technically within plutos orbit. In a sence, your saying like perhaps, tethys is a planet while saturn is its moon! Or europa is a planet, while jupitur is instead the moon?! Make sence? Charon is a moon of pluto. Thats final to me.

Answer 4

Charon is a moon of Pluto because according to current hypothesis Charon was the result of the impact between Pluto and a similar size object. The same way in which our Moon originated.

Answer 5

As for me - I don't think Pluto is a planet. I have always been in favor of the 8 planet system.

HOWEVER - the new definition I saw is not bad. It uses a center of gravity for each system to determine if the body is a planet or a moon. (if I read it right) So for our moon the point lies within the earth itself, so its a moon. But for the dual system of P-C, the center for Charon lies outside Pluto, thus making it a dual system.

And I have always thought there should have been a planet between mars and the gas planets - so this definition solves that, sort of.

Answer 6

Charon's stats Diameter: 1207 km ± 3 km
... ... ... ... ... .....Mass (1.52±0.06)×10^21 kg

Pluto's stats ... Diameter 2306±20 km
... ... ... ... ... ... Mass (1.305±0.007)×10^22 kg

Pluto has twice the diameter and 10 times the mass.

I'd still call Charon Pluto's moon.

Here's my definition of planet.

I would say that the following are minimum characteristics of planets.

1 & 2 below are arbitrary, you may prefer other variables.

1. Minimum Mass. 10^20 Kg. (about 1/100th the mass of Pluto).

2. Minimum Diameter. 1,500 Km (about 900 miles)

3. Orbit. Must be in orbit around a sun, and not a planet (therefore, Luna is not a planet, even though it's larger than Pluto). It must dominate it's orbit with at least 75% of the mass.

4. Distance from sun. Not relevant, as long as it is clearly in orbit around the sun. Therefore, a massive sun may have planets dozen's of light-years away.

5. Is not itself a sun. That would be a binary or higher system.

6. Must not be in interstellar space, not associated with a sun or suns.

7. Not in a field of other bodies with the same approximate orbit. That would leave out anything in the Asteroid Belt and Oort Cloud.

So, I say that Pluto is a planet.

Now, how about "Xena" (aka, 2003 UB313)? To Hades (Greek God of the underworld) with conventions for naming planets. Xena is perfect. And Gabrielle for the moon. If they can name a comet "Hale-Bopp" why not a planet after the Warrior Princess.

Answer 7

Yeah, I know, it's going to be so confusing once they have a definitive...well, definition for planets. I remember doing a huge astronomy project in grade school and have been in love with it ever since. But until we can send something out there to actually monitor Pluto's and Charon's orbits, there's no way to actually grasp what's really going on out there (I really don't think the telescopes can do that).

Answer 8

Was there an actual question in there? The proposed IAU definition would make Pluto/Charon a double-planet system...neither one is a "moon."

Answer 9

yeah, what you said..