Hot gases don’t produce a continuous emission spectrum. Black hydrogen absorption lines are at the same wavelength as the bright hydrogen emission lines. Key fact Line emission spectra are ...

This causes an absorption spectra, as shown below. Because the energy levels are the same, the lines in the emission spectra of an element are in the same position as the lines in the absorption ...

THE numerous absorption spectra of soluble substances which have been described hitherto, have referred as a rule to the solutions of the substances, and but rarely to the solid substances themselves.

https://doi.org/10.1086/674364 • https://www.jstor.org/stable/10.1086/674364 AbstractWe present an analysis of interstellar absorption lines in high-resolution ...

WE have recently been investigating the far ultra-violet absorption spectra of a number of organic compounds of the type R 1 COOR 2; R being an alkyl group or a hydrogen atom. It has been found ...

Through their interaction, it can produce a spectral line in emission or absorption at a wavelength of about 21 centimetres. The strength of this 21 cm spectral line of hydrogen in emission is ...