DURING 1932, work has been carried on in this laboratory on the measurement of the relative intensity of spectral lines in the above elements. The amount of material available was very limited ...

Studying the line spectra produced by hot gases and absorbed by cooler gases allows us to identify the elements in stars. When a gas is very hot, it doesn’t emit all wavelengths of light.

As a result each produces photons with different energy and so the line spectra for different elements will be different. This means that line spectra can be used to identify elements. Continuous ...