The Role of Terahertz and Far-IR Spectroscopy in Understanding the
  Formation and Evolution of Interstellar Prebiotic Molecules
  Stellar systems are often formed through the collapse of dense molecular
clouds which, in turn, return copious amounts of atomic and molecular material
to the interstellar medium. An in-depth understanding of chemical evolution
during this cyclic interaction between the stars and the interstellar medium is
at the heart of astrochemistry. Systematic chemical composition changes as
interstellar clouds evolve from the diffuse stage to dense, quiescent molecular
clouds to star-forming regions and proto-planetary disks further enrich the
molecular diversity leading to the evolution of ever more complex molecules. In
particular, the icy mantles formed on interstellar dust grains and their
irradiation are thought to be the origin of many of the observed molecules,
including those that are deemed to be prebiotic; that is those molecules
necessary for the origin of life. This review will discuss both observational
(e.g., ALMA, SOFIA, Herschel) and laboratory investigations using millimeter,
submillimeter, and terahertz and far-IR (THz/F-IR) spectroscopies and the role
that they play in contributing to our understanding of the formation of
prebiotic molecules. Mid-IR spectroscopy has typically been the primary tool
used in laboratory studies. However, THz/F-IR spectroscopy offers an additional
and complementary approach in that it provides the ability to investigate
intermolecular interactions compared to the intramolecular modes available in
the mid-IR. THz/F-IR spectroscopy is still somewhat under-utilized, but with
the additional capability it brings, its popularity is likely to significantly
increase in the near future. This review will discuss the strengths and
limitations of such methods, and will also provide some suggestions on future
research areas that should be pursued in the coming decade exploiting both
space-borne and laboratory facilities.
