Nasa Perseverance rover to land on Mars in search of life

Spacecraft will descend on red planet carrying helicopter and instruments to look for biosignatures

A rover and a tiny helicopter are preparing to land on Mars, aiming to offer an opportunity to answer an enduring question: has life ever emerged on another planet?

Nasa's ninth mission to descend on the cold, dry, red planet will be steered by a $2.7bn (2.1bn), car-sized, six-wheeled rover christened Perseverance, which is expected to touch down on Thursday following a seven-month journey.