This analysis by Loeb makes no sense to me. If the ‘light’ were due to radioactivity, any inhabitants would have to be shielded, so why would the radioactivity be on the outside, and the inhabitants shielded inside it?
If the interior were to be lit and the ‘spacecraft’ had windows, the light would be far too dim to be visible at this distance. There’s no logical explanation for exterior lighting. There are presently no human built satellites or spaceships with exterior lighting. The reason for that is obvious - it would have no purpose.
Good points—mind expanding.
But why start with ‘radioactivity’ or, even worse, lights (as Avi did)? That’s still anthropomorphic. The ‘glow’ we register as light may be something we can’t yet imagine. Our sensors reduce it to ‘light,’ but what if they’re too primitive to capture the reality—something beyond our comprehension?
Like a grandmother dismissing Steely Dan as noise, we may be missing the real signal.
Or not.;-)