TITLE:
On the effect of the Sun on Kordylewski clouds

AUTHORS:
Joan Gimeno^(1), Angel Jorba^(1,2), Marc Jorba-Cusco^(3) and
Bego\~na Nicolas^(4)

(1) Departament de Matematiques i Informatica,
    Universitat de Barcelona
(2) Centre de Recerca Matematica (CRM), Barcelona
(3) Departament de Matematiques,
    Universitat Politecnica de Catalunya, 
(4) Departamento de Matematica Aplicada,
    Universidade de Santiago de Compostela

ABSTRACT:
In this paper we focus on the existence of dust clouds moving near the
triangular points of the Earth-Moon system, the so called Kordylewski
clouds.  The study is based on using some simplified planar models to
find possible locations for these clouds. The validity of these
predictions is tested by means of numerical simulations on a realistic
model.

The simplified models are based on the Earth-Moon Restricted
Three-Body Problem plus the direct gravitational effect of the Sun on
the particles (this is the so called Bicircular model), the Solar
radiation pressure and the Poynting-Robertson effect. The analysis of
these models shows that there are some stability regions in the
Earth-Moon plane, at some distance of the triangular points.

The stability of these regions has been tested numerically in
realistic (non planar) models.  The results show that particles in
these regions persist for some time (about a century) but it is very
remarkable that many of these particles also escape the Earth-Moon
system. If we perform backwards in time numerical simulations we
obtain a similar result: particles also escape the Earth-Moon system
after a similar time.  From this point of view, the clouds are not a
stable region in the classical sense of the term, but a region with
"slow diffusion" where interplanetary particles stay for some years.