Re: Number of low eccentricity distant planets

"Crown-Horned Snorkack" <chornedsnorkack@[EMAIL PROTECTED]
> wrote in message 
news:5c5a276c-f140-4e79-a13f-8ebe7e9e0df3@[EMAIL PROTECTED]
> On 25 veebr, 23:03, Erik Max Francis <m...@[EMAIL PROTECTED]
> wrote:
>> Crown-Horned Snorkack wrote:
>> > On 23 veebr, 23:40, Erik Max Francis <m...@[EMAIL PROTECTED]
> wrote:
>> >> Mike Williams wrote:
>> >>> Decide what value you consider to be "low eccentricity" and count
off
>> >>> the pro****tion. As a guide, the eccentricity of the Earth is
0.0167.
>> >>> About 16% of those extrasolar planets have orbits that are less
>> >>> eccentric than that of the Earth. I ignored exoplanets for which
the
>> >>> eccentricity has not been calculated.
>> >> Note that there are very strong selection effects here which are
sure 
>> >> to
>> >> affect the distribution of known eccentricities.  The real answer is
>> >> that we don't yet know.
>>
>> > Precisely how do the selection effects affect the distribution?
>>
>> > For one thing, selection effect favour close-in hot Jupiters - and
>> > these tend to have low eccentricities. After excluding the short
>> > period planets, what is the remaining picture?
>>
>> We don't know what the true distribution _actually is_, but we know
that
>> our detection methods favor large bodies, close in.  These are likely
to
>> have a skewed distribution of eccentricities compared to the true
>> distribution, due to tidal effects.
>>
>> That is the whole point here.  We do not know what the actual
>> distribution is, so pretending that what we've found is meaningful is
>> highly premature.
>>
> But my point is that after we remove from our data set the cases which
> we know our detection methods are biased in favour of, what remains
> should be representative.
>
> Start by removing bodies close in. Is the distribution of those found
> to be far away meaningful?

We know about as much about extra-solar systems as Galileo did about the 
distribution of moons in our solar system.