The US space agency’s Perseverance rover is getting ready to take its first sample of Mars rock.
The core, about the size of a finger, will be packaged in a sealed tube for eventual return to Earth.
Scientists say their best chance of determining whether Mars ever hosted life is to study its surface materials in sophisticated home laboratories.
Perseverance landed on the Red Planet in February, in a 45km-wide (30 miles) crater called Jezero.
Satellite images indicate this deep depression once held a lake, fed by a deltaic river.
As such, it is considered a great candidate for the preservation of ancient microbial organisms – if they ever existed.
The NASA robot has driven about 1km (3,000ft) south from where it touched down in dramatic fashion five months ago.
It’s now stopped at a location that’s been dubbed the “Paver Stones”, or “Fractured Rough”.
An area on Mars nicknamed the “Cratered Floor Fractured Rough”
This is a collection of pale-coloured rocks that the mission team believes represents the base, or floor, of Jezero.
The scientists want to determine whether these Paver Stones are sedimentary or volcanic in origin. Either is interesting, but the special quality of volcanic rocks is that they can be dated with very high precision and accuracy in a lab, says chief scientist Ken Farley.
“That would really pin down the timing of many of the things we are looking at on Mars,” he told reporters.
Perseverance will first abrade the surface of a chosen section of Paver Stone, to remove Mars’ obscuring dust, and then examine the site with its powerful instruments.
