In infinite wisdom Christopher M. Jones answered:

"Alfred A. Aburto Jr." <aburto@sbcglobal.net> wrote in message news:<M8crc.1840$9M.936@newssvr27.news.prodigy.com>...

"Rich" <someone@somewhere.com> wrote in message

news:40AA1FC7.3060604@somewhere.com...

Umm, the current one?  By the "current census," I mean the known
extrasolar planets.

Almost exclusively gas giants, only a few oddball terrestrial planets.
I don't see how you can derive that there are "more lower-mass planets
than Jupiter-mass planets" from the data at hand.

It is interesting though to see a plot of the trends ... the number of
extra-solar planets increases greatly as the planet mass decreases:

http://exoplanets.org/science.html

Wrong link, I think you want: http://exoplanets.org/msini.html

The data is suggestive, especially considering the sensitivity
limits of the instruments (which more easily detect more massive planets and cannot detect sub-gas-giant planets at all).
Other investigations, especially the Kepler mission, will give
us much better data on the abundance of lower mass planets.

I'm not at all sure that this simplistic statistical treatment is
valid. The dynamics of planet formation are far from know, and many
of the gas giants are in highly eccentric orbits, which would disrupt
the orbits of any other planets for quite a way in and out. And
it's not even known if terrestrial planets can form as outer
planets, as they would have to in a significant number of the
stars where a gas giant (or 2) has been detected.

Nevertheless, the fairly limited assertion that sub-Jupiter mass
planets exist in greater abundance is pretty well supported by the data on hand (with a few caveats).

Is it? I suggest that this is speculation on the order of the Drake
Equation, and as of yet backed by no data. And I suggest that
for most of the stars where planets have been detected,
terrestrial planets are unlikely or simply impossible due to
the dynamics of the gas giants.

Terrestrial planets may indeed be common, but I don't see any
way that can be extrapolated from the data we have, and I doubt
any will be found at most of the stars where we have detected
gas giants.

Rich