Colombia Ceasfire Ends 52 Year War

A ceasefire has come into effect in Colombia between the main leftist rebel group and the government, ending one of the world's longest insurgencies.

As the fanfare of the Rio Olympics starts to fade, the reality of the political turmoil facing Brazil returns to the fore. Today, Dilma Rousseff, who served as President of Brazil - until her suspension in May -- is scheduled to testify in her own defence at her impeachment trial.

Six people have just emerged after spending 12 months simulating a mission to Mars. The NASA funded project aims to re-create the conditions future astronauts will experience as they live on and research the red planet. We speak to one of the crew as they get a first taste of freedom.