What are hydrogen absorption lines?

Answer by  worker995727 (30)

When light of a particular frequency strikes a hydrogen atom it can cause an electron in orbit around the atom to change to a different energy level. The different orbits have specific energy levels and the absorption lines correspond to the differences between these energy levels. Every time a photon strikes a hydrogen atom it promotes an electron.

Answer by  PowerIsMe (844)

Basically when white light (light containing all frequencies) is incident on Hydrogen, certain specific wavelengths are absorbed. When viewed in a light spectrum, these specific wavelengths are darker - since the Hydrogen has already absorbed it. Thus, the lines are called Hydrogen absorption lines. On a parallel line, one can also define Hydrogen emission lines (wavelength that Hydrogen emits)