Just the sky? Based on images Ibu had studied... "If so, that must mean we are getting closer to the water. As you may recall, the closer to the water, the more the sky takes on a deeper hue. What we might refer to as 'twilight'," he said excitedly. "It is also likely that we will experience a drop in temperature once we step outside of the vehicle." Which meant he needed to pack his camera into its weather-proof casing.