NASA says it Curiosity rover on Mars is being prepared to bore into a rock, the third such drilling into the surface of the Red Planet.
The target sandstone rock, dubbed "Windjana," could yield important clues to possible life-friendly conditions in the planet's distant past, scientist at NASA's Jet Propulsion Laboratory in Pasadena, Calif., said.
A test drilling into Windjana, named after a Western Australia gorge, was conducted April 30 to a depth of around 0.8 inches, they said.
Drilling dust, which was a grayish color quite different from the reddish-brown that is characteristic of the surrounding surface, was cleared from the rock with a wire brush wielded by the rover.
"In the brushed spot, we can see that the rock is fine-grained, its true color is much grayer than the surface dust, and some portions of the rock are harder than others, creating the interesting bumpy textures," JPL Curiosity science team researcher Melissa Rice said. "All of these traits reinforce our interest in drilling here in order understand the chemistry of the fluids that bound these grains together to form the rock."
Drilling will hopefully provide clues to what the environment on Mars was like during the time the sandstone was laid down, the researchers say.
That difference in hardness in some parts of the rock is significant, they say, since the hardness or softness of rocks can determine how landscapes are shaped, with softer areas eroding away much faster than harder ones.
"We want to learn more about the wet process that turned sand deposits into sandstone here," Curiosity lead scientist and Caltech geologist John Grotzinger said. "What was the composition of the fluids that bound the grains together?"
In the planned drilling, powdered material will be collected from the rock's interior and delivered to scientific instrument inside the rover.
Curiosity had sampled just two rocks before arriving at Windjana, drilling into two adjacent mudstone slabs at Yellowknife Bay, around 2.5 miles northeast of its current location.
Samples were analyzed and yielded evidence of a possible ancient lakebed, an environment that may have contained key chemicals and a source of chemical energy that could have created conditions for microbial life to exist billions of years in the past, NASA said.