Pretty normale episode last Sunday.
Anyway, a quote from the 4th episode:
As we look up into space we can see the light from stars that no longer exist, it truly is a sky full of ghosts. In one second light travels 186,000 miles, that is nearly the distance between the earth and the moon. The moon is therefore around 1 light second away, so when you next look at the moon, remember that you are looking one second into the past.