... The Lyman Alpha Forest . ... Strewn throughout the universe are "trees" of hydrogen gas that absorb light from distant objects. These gas clouds leave numerous absorption lines in a distant quasar's spectra, together called the Lyman-alpha forest. M104: The Sombrero Galaxy . ... Named the Sombrero Galaxy for its hat-like resemblance, M104 features a prominent dust lane and a bright halo of stars and globular clusters. ... Galaxies are made up of stars, but are all stars found within galaxies? ...