- #1
ACG
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Hi!
I saw the definition of a planet -- basically anything differentiated that has cleared everything in the area and orbits the central star.
Pluto doesn't count because it's in the middle of a belt.
Ceres doesn't count because it's in the middle of a belt.
Sedna -- well, Sedna's an interesting case. You see, its aphelion is INSIDE the Oort Cloud and its perihelion is OUTSIDE the Kuiper Belt.
Even astronomers aren't sure how it got there. This probably means there isn't much out there.
So we have a large object in a zone which appears (at least for the time being) to have nothing in it.
This makes Sedna a planet -- at least temporarily. It's basically in the same position Pluto was in 1930 -- it's in an area where there are no other known bodies. Perhaps we'll find some more Sednas in the future, in which case Sedna can be downgraded. But for now -- it sure fits the definition! The definition says nothing about how eccentric the orbit is.
What's wrong with this reasoning?
ACG
I saw the definition of a planet -- basically anything differentiated that has cleared everything in the area and orbits the central star.
Pluto doesn't count because it's in the middle of a belt.
Ceres doesn't count because it's in the middle of a belt.
Sedna -- well, Sedna's an interesting case. You see, its aphelion is INSIDE the Oort Cloud and its perihelion is OUTSIDE the Kuiper Belt.
Even astronomers aren't sure how it got there. This probably means there isn't much out there.
So we have a large object in a zone which appears (at least for the time being) to have nothing in it.
This makes Sedna a planet -- at least temporarily. It's basically in the same position Pluto was in 1930 -- it's in an area where there are no other known bodies. Perhaps we'll find some more Sednas in the future, in which case Sedna can be downgraded. But for now -- it sure fits the definition! The definition says nothing about how eccentric the orbit is.
What's wrong with this reasoning?
ACG