[radicalbyte]

This thread is very confused.

There are two things: the radar images are created with radio waves emitted by the radar installation. The second thing is that the visualisation shows a light source. They are unrelated to each other. I assume that the light source was added during rendering of the film and that it approximates the sun.

[TorKlingberg]

I don't think the visualisation shows any light source. The radar reflection from the asteroid just looks like it is "lit up"

[ceejayoz]

The radar is the light source, just like shining a flashlight during the night at something.

The actual solar illumination of the asteroid at the time was likely significantly different from what we see in these images.