Re: Soon 12 planets in the solar system !


<tony_flanders@xxxxxxxxx> wrote in message
news:1155734360.814689.207190@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
The IAU definition says:
...

Thierry wrote:

I am agree with any definition, but between us, is it logical ?
...
But up to now, the common sense - which of course is not a scientific
concept, tells that any object orbiting a planet is a satellite.

Whether the definition *really* makes sense will have to wait until we
know
more about how planets and satellites (to say nothing of stars!) form.

But whether you agree with it or not, the definition is clever and
farsighted.
Remember, we'll be finding lots more KBOs out there, and learning more
about the KBOs that have been found. With a 10:1 mass ratio, common
sense says that Charon is Pluto's satellite. But what if the mass ratio
were 2:1? What about 1.5:1, or 1:1? How much money would you bet
that we *won't* find a system like that?

Hi Tom,

For sure idem for some KBO, many have probably a rounded shape and are
probably as big as Charon, etc.
I also read all the litterature about the definition of a planet including
Michael Brown's pages, etc.
I am nothing against IAU definition including mass, radius and barycenter
which is very smart and clear but on another side one speeks of the
"Earth-Moon couple", isn't it, and more than one physicist consider it as a
true physical couple due to their size and proximity.... where ever could be
the barycenter...

Thierry





- Tony Flanders



.

Relevant Pages

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