Fig. 8
From: An uppermost haze layer above 100 km found over Venus by the SOIR instrument onboard Venus Express
Panel 1: Typical evolution through time of the signal (in ADU) on one pixel of the detector during a solar occultation. This example corresponds to an egress: at the beginning, no light reaches the detector when VEX is in the umbra region (black line); then, the occultation occurs when VEX is in the penumbra region (red line); finally, the instrument looks directly at the Sun and measures exoatmospheric raw spectra (blue line). The exoatmosphere and umbra zones used to derive the noise are indicated by the boxes. Panels 2 and 3: Variation of the noise signal around the mean value of the two zones (exoatmosphere in Panel 2 and umbra region in Panel 3). The standard deviations are shown by the lines in green (taken from A.C. Vandaele et al. 2013)