Metallicity is a measure of the relative abundance in a star of elements other than hydrogen and helium.

金属丰度是对恒星内除氢和氦之外元素的相对丰度的度量(天文学中比氦重的元素都叫金属。——译者注)。

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Energy resources that can be harvested in space for the benefit of Earth include helium-3 that occurs in abundance on both the Moon and asteroids and is ideal for new small fusion plants, as well as solar energy that can be collected and transmitted in concentrated form to Earth.

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