Gaia is an ESA mission due to be launched in 2013 and will be dedicated to astrometry. The attitude of the spacecraft
Gaia is an important part of the data processing of the mission because the astrometry will be calculated with respect to the
attitude. Therefore we need a very accurate characterisation of the attitude of the satellite during the observations in order
to get the best output from the mission.
We simulate the attitude of Gaia using the Dynamical Attitude Model (DAM). It is a simulation developed to achieve a
detailed understanding of the Gaia attitude and to provide realistic input data for testing the software pipeline. DAM takes
into account perturbations as well as internal hardware components controlling the satellite as the control system, sensors
and micro-Newton thrusters.
We study the errors in the simulated data, specifically the attitude reconstruction when fitting the Gaia reference attitude
with B-splines. We analyse the effect of different parameters and provide an estimation of the expected noise in the scientific
output of the mission due to the noise in the attitude reconstruction.