Cosmic Clouds: Birth, Death, and Recycling in the Galaxy

Rating:
Summary: Star cycles
Review: Easy to read overview of astronomical techniques such as measuring distances of distant bodies and interpreting spectral patterns, as well as stars, nebulae, and star and planet formation. The cosmic cycle of interstellar clouds collapsing, the formation of stars, the death of stars with dust and enriched matter going back to interstellar clouds, is described. The Big Bang is theorized to have only created hydrogen, helium and a bit of lithium, with heavier elements produced in stars later. It is thus interesting to note that while older parts of our galaxy contain stars with very low levels of heavy elements, no stars have yet been discovered containing no metals, ie, with only the hydrogen, helium and lithium of the Big Bang.