  A diurnal varying haze layer at the bright spots of Occator on dwarf planet
Ceres has been reported from images of the Dawn Framing Camera. This finding is
supported by ground-based observations revealing diurnal albedo changes at
Occator's longitude. In the present work, we further investigate the previously
reported haze phenomenon in more detail using additional Framing Camera images.
We demonstrate that the light scattering behavior at the central floor of
Occator is different compared to a typical cerean surface and is likely
inconsistent with a pure solid surface scatterer. The identified deviation is
best explained by an additional component to the scattered light of the
surface, i.e., a haze layer. Our results support the water vapor detection by
Herschel observations though the existence of a tenuous cerean exosphere is not
yet confirmed.
