Nearly all of the instruments packed into Mars rover Curiosity‘s frame have been utilized, but once crucial test has yet to be performed. NASA scientists will soon use Curiosity’s percussive drill to powder the interior of a rock for analysis, something that has never been done on Mars.

To choose the perfect rock for the drilling, the rover is currently driving around in a shallow depression named “Yellowknife Bay.” The area has a different type of terrain than any Curiosity has yet encountered on Mars. It is one of three different terrain types that intersect at an area named “Glenelg,” which has been the rover’s interim destination since around two weeks after it landed back in August.

The Curiosity team stationed at NASA’s Jet Propulsion Laboratory (JPL) used the rover’s Mast Camera (Mastcam) and Chemistry and Camera (ChemCam) to study rocks while driving toward two particular rocks of intrest. Named “Costello” and “Flaherty,” the two rocks have now been examined using the rover’s Alpha Particle X-Ray Spectrometer (APXS) and Mars Hand Lens Imager (MAHLI).

Curiosity has one more drive planned for this week before the rover team’s holiday break. During the break, the environment in Yellowknife Bay will continue to be studied, and early next year the rover will perform its historic drill sampling. For most of next year, the plans for the rover consist of continued sampling and investigation while driving toward a 5-kilometer-high (3 mile) layered mound named “Mount Sharp.”