The new manuscript, “1.34 billion-year-old magmatism on Mars evaluated from the co-genetic nakhlite and chassignite meteorites“, by Arya Udry and James Day (Scripps Institute of Oceanography UCSD), presents the most comprehensive study of any coherent and linked suite of igneous rocks from a planetary body outside of the Earth or Moon. A comprehensive approach allows to study planetary samples like terrestrial rocks. By using quantitative textural analyses, mineral and bulk composition analyses, our study confirms the petrological link between nakhlites and chassignites, similar to terrestrial lava-sill-dike complexes.Mineral and bulk compositions of these meteorites suggest they have undergone <5% partial melting of a highly depleted source, followed by fractionation of olivine and pyroxene. Although the timing of emplacement and spatial distribution of these magmatic bodies is not well known, we show that these rocks were emplaced as not one single flow as previously suggested, but as multiple flows, and possibly different volcanic edifices. Fluid alteration then followed the emplacement of nakhlite and chassignite flows/dikes/sills.