[meteorite-list] PLUTOID CORRECTIONS

Sterling K. Webb sterling_k_webb at sbcglobal.net
Thu Jun 12 04:29:00 EDT 2008


    Sorry for the mis-spellings. A couple of corrections.
The smaller is bigger magnitude scale always did mess
me up. Brown should get both 2005 FY9 and 2003 EL61
assigned as "Plutoids," although not necessarily as "dwarf"
planets:

    "The dwarf planet/plutoid classification of new discoveries 
is now a preliminary one: You get a plutoid-style name when 
you're bright enough but the jury is still out on whether you 
also fulfill the key dwarf planet criterion on hydrostatic 
equilibrium - thus the plutoid status could be taken away 
from you any time in the future." [Daniel Fischer, comment on
http://www.mikebrownsplanets.com/2008/06/plutoid-fever.html ]

    Ted Bowell (Lowell Obs.) on:
http://www.astro.uni-bonn.de/~dfischer/mirror/317.html
    "There have also been proposals to replace the much-attacked 
'dwarf planet' by something else, but Bowell et al. "felt that, 
most likely, too much time had now passed since the Prague 
IAU General Assembly to make a change. Thus, we appear 
to be stuck with the term 'dwarf planet'. "

    Even the astronomers making the discoveries have no idea
what the IAU either means, nor what they mean to do, apparently.
They seem to think the H = +1.0 limit applies only to NEW
discoveries (which would mean a long list of Plutoids would be
approved as Plutoids, if not dwarf planets).

The IAU said:
    "it was decided that, for naming purposes, any Solar System 
body having (a) a semimajor axis greater than that of Neptune, 
and (b) an absolute magnitude brighter than H = +1 magnitude 
will be considered to be a plutoid."

    This does not sound to me like they're talking about new
(still to be made) discoveries. It sounds like they're ruling out
the large number of existing discoveries with magnitudes
greater than +1.0.

    We will see when they dispose of naming.


Sterling K. Webb




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