In infinite wisdom Joseph Lazio answered:

"R" == Rich  <someone@somewhere.com> writes:

R> In infinite wisdom Christopher M. Jones answered:

I think you want: http://exoplanets.org/msini.html The
data is suggestive, especially considering the sensitivity limits
of the instruments (...).  Other investigations, especially the
Kepler mission, will give us much better data on the abundance of
lower mass planets.

R> I'm not at all sure that this simplistic statistical treatment is
R> valid. The dynamics of planet formation are far from know, and many
R> of the gas giants are in highly eccentric orbits, which would
R> disrupt the orbits of any other planets for quite a way in and
R> out. [...]

Please explain how the orbital dynamics of these planets would affect
the measured mass distribution.

Orbital resonances with the more massive planets dictate where
stable orbits exist.

---

http://en.wikipedia.org/wiki/Orbital_resonance

Orbital resonance

From Wikipedia, the free encyclopedia.

In celestial mechanics, orbital resonance occurs when two orbiting bodies have periods of revolution that are in a simple integer ratio so that they exert a regular gravitational influence on each other. This can stabilize the orbits and protect them from gravitational perturbation. For instance:

    * Pluto and some smaller bodies called Plutinos were saved from
      ejection by a 3:2 resonance with Neptune.
    * The Trojan asteroids may be regarded as being protected by a 1:1
      resonance with Jupiter.

Orbital resonance can also destabilize one of the orbits. For instance:

    * There is a series of almost empty lanes in the asteroid belt
      called Kirkwood gaps where the asteroids would be in resonance
      with Jupiter.

A Laplace resonance occurs when three or more orbiting bodies have a simple integer ratio between their orbital periods. For example, Jupiter's moons Ganymede, Europa, and Io are in a 1:2:4 orbital resonance.

See also

    * Lagrange points
    * Tidal locking

---

A gas giant close to a star makes it difficult for stable orbits to
exist in the habitable zone.

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).

R> Is it? I suggest that this is speculation on the order of the Drake
R> Equation, and as of yet backed by no data.

Whew!  Will somebody please explain to me why I continue to post on
this topic?  Even better, will somebody please tell me what to say?

>

How one can look at a mass distribution, taken from the inferred
masses of planets, and claim that it is "backed by no data" is just incredible.

Then show me the data for terresitral mass planets. I'd appreciate it.
Somehow I've missed all the announced discoveries of terrestrial mass
planets. Just call me Rip Van.

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

Ah, good.  Given your statements above, Is it worth looking for
extrasolar terrestrial planets? 

Is it worth looking for gravity waves? Despite the fact that LIGO has
found nothing, physicists think it's a smashing success. And the
question remains, what next? Do we build a larger LIGO? And a larger
one after that, and keep going until we find something? It's clear
that this is what the Physics community would do. But let's say that
you get to pay for part of it, say, it costs every taxpayer $10-20
a year, and $20-30 a year for the next one. And let's say that the
money spent is borrowed and inflationary (unreasonable conditions
though these may be :-). What are you going to decide?

Rich