  We present our investigations of the physical and dynamical properties of
selected Earth co-orbital asteroids. The photometric optical light curves as
well as rotation periods and pole solutions for a sample of four Earth
co-orbital asteroids, namely (138175) 2000 EE104 (P=13.9476+/-0.0051 hrs),
(418849) 2008 WM64 (P=2.4077+/-0.0001 hrs), 2016 CA138 (P=5.3137+/-0.0016 hrs)
and 2017 SL16 (P=0.3188+/-0.0053 hrs), are determined or improved and presented
in this work. For this investigation, we combine observations carried out at
the Bulgarian National Astronomical Observatory - Rozhen using the FoReRo2
instrument attached to the 2mRCC telescope as well as sparse data from AstDys2
database. Parallel to the rotational properties we did numerical dynamical
simulations to investigate the orbital stability of those objects and to find
out if there is a relation with their rotational properties. Our results show
that the orbit stability is affected by the orbit itself and mainly its
eccentricity and inclination, which are responsible for the close encounters
with other Solar system planets. We cannot make a definitive conclusion about
the relation between orbit stability and the rotational state of the asteroids,
so we need further investigations and observations in order to prove or
disprove it.
