Pre-Launch Calibration Target for ChemCamThis image shows the calibration target for the Chemistry and Camera instrument on NASA's Curiosity rover before it was installed on the rover and readied for launch.
The target includes nine circles of materials scientists expect to see on Mars and one titanium square with a painted edge. According to the numbering in this image, the circles in the top row show four glass samples likely to represent Mars igneous rock compositions, plus a graphite rod on the right side. The bottom row shows four ceramic samples representing Mars sedimentary rock compositions and a titanium plate for wavelength calibration and laser diagnostic tests.
Image Credit: NASA/JPL-Caltech/LANL