Earth must have gotten its water around the same time the eucrites did—which has big implications.
因此地球应该和这个小行星群同一时期拥有水源—这样的推理影响重大。
科学60秒 听力 2014年11月合集
The scientists discovered that the chemical signature of water on Earth matches the signature of water in an ancient group of asteroids called eucrites.
Eucrites are achondritic stony meteorites, many of which originate from the surface of the asteroid 4 Vesta and as such are part of the HED meteorite clan. They are the most common achondrite group with well over 100 distinct finds at present.
Eucrites consist of basaltic rock from the crust of 4 Vesta or a similar parent body. They are mostly composed of Ca-poor pyroxene, pigeonite, and Ca-rich plagioclase (anorthite).