0 the study of the way matter absorbs or sends out light and other radiation (= energy from light or heat that you cannot see) : --
Scientists have determined the proportions of the chemical elements present in the Sun using spectroscopy.
His work in spectroscopy led to an understanding of the origin of the remarkable colours of gem stones.
We can complete it step by step however long the road is and it can't be completed however short the road is if you don't even mark your footprint.
Vi kan slutföra det steg för steg hur lång vägen än är och den kan inte slutföras hur kort vägen än är om du inte ens markerar ditt fotavtryck.