noun
metallicity; metal abundance
Astronomical term for the proportion of elements heavier than helium in a star or other celestial body. Often expressed as [Fe/H] or similar logarithmic ratio.
この星の金属量は太陽の約半分である。
The metallicity of this star is about half that of the Sun.
金属量が低い恒星は宇宙の初期に形成されたと考えられている。
Stars with low metallicity are thought to have formed in the early universe.