For roughly the first three decades of his career, Spielberg tended to take a fairly sanguine view of aliens, refusing to succumb to the disaster-movie framework of aliens attacking terrified Earthlings. That changed in a big way after 9/11, when Spielberg made a couple of Tom Cruise -starring sci-fi blockbusters grappling with a changed world.

Early cinema depicted aliens as human-like for familiarity and practical reasons, but modern science fiction explores unrecognisable forms, challenging perception and our capacity to comprehend the truly alien.

We talk to astronomer Professor Jon Willis about what form alien life may take based on evidence we find on Earth

In the following six books, each writer looks to space to skillfully explore what it means to live on Earth. Salvation and exploitation go hand in hand in this story by one of science fiction’s all-time greats.

Filmmakers have shaped our perception of the unknown, and Steven Spielberg has had aliens on the mind for a while now. He even believes they have been to Earth and may still be amongst us. Will his depiction of alien lifeforms in his anticipated new film 'Disclosure Day' challenge audiences?

Scientists are listening in on sperm whale conversations and studying Earth's strangest microbes to prepare humanity for first contact with extraterrestrial life.