A set of well-defined lines within the electromagnetic spectrum, emitted by hot or excited matter.
A set of well-defined lines within the electromagnetic spectrum, emitted by hot or excited matter. Each line corresponds to a difference between two possible energy levels in an atom or molecule, and every element has a distinctive set of emission lines. This allows astronomers to tell exactly what distant stars are made of.
Each line corresponds to a difference between two possible energy levels in an atom or molecule, and every element has a distinctive set of emission lines. This allows astronomers to tell exactly what distant stars are made of.