  Quasar absorption lines provide detailed information on the chemical,
kinematic, and ionization conditions in galaxies and their environments, and
provide a means for studying the evolution of these conditions back to the
epoch of the first quasars. Among the collection of absorbing structures along
the lines of sight to quasars there is an evolutionary sequence of galaxies
that represent predecessors of the Milky Way and provide a direct view of its
history. Absorption spectra of lines of sight through the Milky Way and through
nearby galaxies reveal a variety of chemical species, ionization conditions,
and kinematic substructures. These absorption profiles are produced by low
density gas distributed in rotating disks, high velocity halo clouds, satellite
galaxies and their debris, superbubbles, and other sub-galactic gaseous
fragments. Guided by knowledge gained by studying nearby galaxies, we are
developing interpretations of the variety of observed absorption signatures.
Images of .4 < z < 1 galaxies responsible for MgII absorption also allow us to
explore the statistical connections between the galaxy properties and their
gaseous content. Quasar absorption lines are fast becoming a powerful
evolutionary probe of gaseous conditions in the Milky Way.

Astrophysics