A stellar embryo—a protostar—grows in a womb of
molecular gas so choked with dust that visible light has little
hope of passing through. Viewed in an optical telescope, these
dusty wombs appear to be nothing more than dark patches in the
sky. Fortunately, the field of stellar embryology has recently
turned a corner with the development of large telescopes and
sensitive infrared detectors that allow direct measurements of
these objects for the first time. Stellar embryologist Tom
Greene explains how these recent observations are helping
astronomers understand the earliest stages of star formation.