is a term used in astronomy to describe the abundance of elements other than hydrogen and helium. Note that these 'metals' include elements that are not typically considered metallic.
Found on
http://en.wikipedia.org/wiki/Glossary_of_astronomy
The point of this notation is that if a mass of gas is diluted with pure hydrogen, then its [Fe/H] value will decrease (because there are fewer iron atoms per hydrogen atom after the dilution), but for all other elements X, the [X/Fe] ratios will remain unchanged. By contrast, if a mass of gas is polluted with some amount of pure oxygen, then its ...
Found on
http://en.wikipedia.org/wiki/Metallicity
A measure of the proportion of 'heavy elements' or 'metals' (in astronomy, elements heavier than hydrogen or helium) that a star contains. Usually, metallicity is given in term of the relative amount of iron and hydrogen present, as determined by analyzing absorption lines in a stellar spectrum, com...
Found on
http://www.daviddarling.info/encyclopedia/M/metallicity.html
No exact match found.
