“Even Dr Who might be taken aback at the sight of these aliens.

The bizarre jellyfish-like beings were dreamed up by a British scientist as an example of life “not as we know it”.

This is what evolution might have come up with on a world such as Saturn’s moon Titan, Dr Maggie Alderin-Pocock believes. She envisages creatures that float through clouds of methane, scooping chemical nutrients into their gaping mouths.”