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How can scientists tell that EETA79001 came from Mars?

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Meteorite The Hoba meteorite, lying where it was discovered in 1920 near Grootfontein, Namibia. The largest meteorite on Earth and an iron meteorite by classification, it consists of a nickel-iron alloy and is estimated to weigh about 60 tons.

Scientists confirmed that the meteorite EETA79001 originated from Mars primarily by analyzing trapped gases within the rock.1

During the violent impact event that ejected the rock from the Martian surface, gases from the planet's atmosphere became trapped in glasses formed by the shock. When scientists analyzed these trapped noble gases, nitrogen, and carbon dioxide, they found that their relative abundances and isotopic compositions were almost identical to measurements of the Martian atmosphere taken by the Viking landers.12

Additional evidence supporting a Martian origin for this and other similar meteorites includes:
* Geological Age: The rocks are volcanic and exhibit relatively young crystallization ages (between 150 million and 1.3 billion years), indicating they originated from a large, geologically active body rather than an asteroid.21
* Geochemical Signatures: The rocks possess distinct oxygen isotope ratios that differ from those found in Earth rocks, lunar samples, and other known meteorites.2