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Old August 27th 06, 10:31 PM posted to sci.astro.amateur,sci.astro
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Default Alan Stern has definitely flipped


ET wrote:

However, in a 2002 paper (referenced in a subsequent paper linked from
this forum)
entitled "Regarding the criteria for planethood and proposed planetary
classification
schemes", Stern and a colleague studied the "dynamical dominance" of
bodies in the solar system and found a "gap of five orders of magnitude
between the smallest terrestrial planets
and the largest asteroids and KBOs".

Think about that. FIVE ORDERS of magnitude. That is freaking huge.


That's a five order of magnitude difference *in the Stern-Levinson
parameter*, M^2/P. The IAU could have used the Stern-Levinson
parameter, or simply drawn some line in terms of mass or radius, but
the fact is, they didn't.

And yet now Stern wants to assert that the glorified rocks in the
various Lagrange zones of
the 8 planets somehow disqualifies them from planethood, despite the
fact that he is
perfectly aware of the huge, qualitative difference involved.


Stern is pointing out, correctly, that the "definition" is
near-gibberish which does not define what the terms it employs mean.
And the trojan asteroids are not all "glorified rocks"; Hektor, for
example, is about 370x195 km in size. Some rock.

Some of Alan Stern's contradictions:

################################################## ###########

1st contradiction:

(originally Alan Stern writes that there is clear distinction
between "uberplanets" and "unterplanets", now 6 years later
he says there is no clear dividing line between them)


There *is* a clear gap in terms of the Stern-Levinson parameter, which,
however, the IAU does not use.

"Hence, we define and uberplanet as a planetary body
in orbit about a star that is dynamically important enough
to have cleared its neighboring planetesimals in a Hubble time.
And we define an unterplanet as one that has not been able to do so."


That does look like a flip, but "planetesimals" is an important word
here. They go on to cook up Lambda = M^2/P, the parameter I've been
talking about, and relate it theoretically to this definition.