The impact of bright extended sources on the observation and detection of faint sources by Gaia has been studied. The effect has been characterized using the representative case of stars near the Jupiter disk and consists of three parts. First, an analytical representation of the PSF, including aberrations and electronic distortions, has been developed to produce images of Jupiter and solar type stars. Second, those images have been combined to produce fields of view including Jupiter and stellar patterns. Third, the CCD images have been fed to the VPU algorithms prototype to determine the limits until which detections are possible. This work can be useful for science cases such as GAREQ.