A Penguin Classic.

With a clever cover by David Pelham, this careworn paperback edition of astronomer Fred Hoyle's 1957 classic science fiction novel The Black Cloud is my new tea break read for this week.

If you stare at the purple disc for a few seconds, then look into the dark mass of the black, the afterimage of that disc will appear to be yellow, the complementary colour of purple; a glowing Sun swallowed by the interstellar cloud of the title.