This week NASA's Perseverance rover will abrade a rock nicknamed "Rochette" on the Martian surface so that scientists can determine if it would hold up under the the rover's powerful coring drill. The core sample will be somewhat thicker than a pencil, and sealed and stored in a titanium tube on the rover. It is hoped the rock core can be returned to Earth to look for signs of ancient microbial life, as well as provide information on the composition of Mars' atmosphere.