The Curiosity Rover recently collected samples from a Martian sandstone, boring deep within the rock. The sandstone, dubbed "Windjana," is located near the foothills of an unusual formation known as Mount Sharp that rises three miles into the sky. Scientists hope that mineral and chemical analysis may help yield clues as to why Mars' environment changed so radically. More at Space.com.
Pictured: Image from Curiosity's Navigation Camera, showing two holes drilled into sandstone target "Windjana."