Quantitative Classification of Igneous Rocks Based on Chemical and Mineral Characters, with a Systematic Nomenclature. By Whitman Cross Joseph P. Iddings Louis V. Pirsson Henry S. Washington ...

Forbes contributors publish independent expert analyses and insights. Amanda Kooser covers the quirky side of science and space.

Mars attracts attention in an odd way. This time, it has to do with a skull-shaped rock rather than cold poles or old rivers. This image from NASA’s Mars Perseverance rover, taken by the Mastcam ...

However, recent chemical analyses by Perseverance’s SuperCam instrument suggest that Skull Hill’s composition does not match typical meteorites. Instead, it may be an igneous rock formed from magma or ...