He had some words about the appearance of the Sun from the surface of Titan:
It is interesting to compare the brightness and colour of the scene shown in Fig. 4 with that of a similar scene on the Earth. The brightness of the surface of the Earth illuminated by full sunlight is about half a million times greater than when illuminated by a full moon. The brightness of the surface of Titan is about a thousand times dimmer than full solar illumination on the Earth (or 500 times brighter than illumination by full moonlight). That is, the illumination level is about that experienced about 10 min after sunset on the Earth. The colour of the sky and the scene on Titan is rather orange due to the much greater attenuation of blue light by Titan's haze relative to red light. If the Sun is high in the sky, it is visible as a small, bright spot, ten times smaller than the solar disk seen from Earth, comparable in size and brightness to a car headlight seen from about 150 m away. The Sun casts sharp shadows, but of low contrast, because some 90% of the illumination comes from the sky. If the Sun is low in the sky, it is not visible.
--Chris