For readers who want the full picture
Detailed explanation
Chemistry, isotopes, ages and gases trapped in some samples connect these meteorites to Mars.
Principal groups are shergottites, nakhlites and chassignites, with rare orthopyroxenites and basaltic breccias.
- Main groups
- shergottite · nakhlite · chassignite
How material leaves Mars
Only highly energetic impacts can accelerate near-surface rock without completely destroying it. Travel times and terrestrial find histories differ from specimen to specimen.
Evidence for a Martian origin
The strongest evidence comes from gases trapped in shock-melted inclusions whose composition matches the Martian atmosphere measured by spacecraft. Oxygen isotopes, mineral chemistry and comparatively young crystallisation ages reinforce the case.
Attribution is therefore not based on red colour. Many Martian meteorites look grey, greenish or black, while terrestrial basalts may appear similar. Laboratory evidence is required.
Major groups and their rocks
Shergottites are the most common group and range from basaltic to olivine-rich rocks. Nakhlites are clinopyroxene-rich cumulates, chassignites olivine-rich intrusive rocks. The orthopyroxenite ALH 84001 records a much older history.
Regolith breccias can mix Martian surface material and atmospheric components. All were launched by very large impacts; the challenge is achieving escape speed without melting all ejected rock.
Short & simple
The essentials in 30 seconds
- Igneous rocks from Mars launched into space by large impacts.
- Chemistry, isotopes, ages and gases trapped in some samples connect these meteorites to Mars.
- Principal groups are shergottites, nakhlites and chassignites, with rare orthopyroxenites and basaltic breccias.
Sources & editorial note
Sources & databases
Editorially paraphrased prefill, reviewed 12 August 2026. The linked sources support further specialist verification.