kē / xué / jiā / tōng / guò / yán / jiū / gǔ / lǎo / yán / shí / lái / liǎo / jiě / míng / gǔ / zhòu / de / huán / jìng科学家通过研究古老岩石来了解冥古宙的环境。Scientists study ancient rocks to learn about the environment of the Hadean eon.