(meteorobs) August Eridanids and 273P Pons-Gambart?

[Roberto Gorelli]

On Tue, 13 Aug 2013 19:55:17 +0200
  "Marcin Gawronski" <motylek at astro.uni.torun.pl> wrote:
>> On Tue, 13 Aug 2013 17:14:06 +1000
>>   "Michael Mattiazzo" <mmatti at westnet.com.au> wrote:
>>> Hi all,
>>>
>>> Now that the orbit of comet 273P Pons-Gambart is now well
>>>determined,
>>> is the link with the august Eridanids confirmed?
>>> and would we expect enhanced activity at this time?
>>> I notice the MOID is 0.17AU so not likely to create meteor shower?
>>>
>>> regards,
>>> Michael Mattiazzo
>>
>> Sorry for the bad English.
>>
>> Each time that I see the Perseids from Italy I see too some 
>>Eridanids
>> coming from South and with a radiant under the horizon, Eridanids 
>>with
>> slow earthgrazing traiectories.
>>
>> On the topic: too other comets doing origin to meteor showers have
>> today big MOIDs, the fact that 273P has today a MOID of 0.17 AU it's
>> not significative, perharps in the past this MOID was near zero.
>>
>> On the specific topic: I'm doing a search for write the page on
>> Eridanids for italian Wiki
>> and I found that exist many meteor radiants in Eridanus in August, 
>>the
>> principal are Eta Eridanids and Epsilon Eridanids and .... their
>> parent it's not 273P! Their parent comets are probably the following
>>
>> http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=C%2F1852+K1&orb=1
>>
>> http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=C%2F1854+L1&orb=1
> 
> Dear all,
> 
> I must say I am little bit surprised that there is still a believe 
>that
> long period comets (P>10^4-5) could be responsible for meteor 
>activity.
> Simulations of orbit evolutions of such comets clearly show that the
> perihelion distance vary a lot from one return to another. The 
>possibility
> for creation of a stream which could result in any meteor activity 
>is
> simple negligible.
> 
>For example please look at:
> http://apollo.astro.amu.edu.pl/PAD/index.php?n=WikicometPub.2011L4
> 
> where the evolution of C/2011 L4 orbit is shown.
> 
> regards,
> 
> Marcin Gawronski

Very interesting paper but I think that it not work for Eridanids.

C/1852 K1 Chacornac was observed only during 28 days and for only 31 
positions

C/1854 L1 Klinkerfues was observed only during 54 days and for only 
227 positions

That I want to said it's that at that time (XIX Century) it was 
standard to think
that a comet was in parabolic orbit if it not show in clear mode that 
it was periodic
(no more of 200 years). 273P/Pons-Gambart was observed only during 30 
days in the same
period and its period was calculated in 57,5 years now we know that it 
has a period of
187,47 years. I thin that C/1852 K1 Chacornac and C/1854 L1 
Klinkerfues can to have
period of only 200-300 years, this it's only a possibility but it 
cannot rule out or
a or some people(s) calculated recently their orbits with the new 
values of the mass
of planets? It should be very interesting to can read a work similar 
at that show
us by Marcin Gawronski on C/2011 L4 calculated for this two comets.
Volunteeers?
Best greetings.
Roberto Gorelli