The Curiosity Mars rover has begun the long - and potentially fatal - trek to its primary mission destination, Mount Sharp.
Since it landed seven months ago the Nasa robot has been examining a site near its touchdown point analysing rock composition.
Curiosity faces a five mile journey to the base of the 18,000ft mountain - expected to take around nine months.
Nasa scientists hope the area will show how the martian planet's environment changed and evolved.
It won't be easy. Perilous sand dunes could trap the rover if it is not steered accurately.
The Curiosity mission has already been a resounding success.
Its primary goal to find "evidence for an ancient wet environment that had conditions favorable for microbial life" has already been accomplished.
Curiosity is one of two functioning rovers on Mars. The other, Opportunity, celebrated the 10th anniversary of its launch on Tuesday.