Source: wikibot/damped-lyman-alpha-system
= Damped Lyman-alpha system
{wiki=Damped_Lyman-alpha_system}
A Damped Lyman-alpha system (DLA) is a type of astronomical object observed in the spectra of distant quasars and galaxies. It is characterized by a strong absorption feature in the Lyman-alpha transition of hydrogen (at a wavelength of 121.6 nm) due to neutral hydrogen gas in the intervening medium.