"The study of the origin of the chemical elements embraces both
nearby stars and galaxies and the most distant quasars we can observe.
The properties of stars and the interstellar gas in our own Galaxy
and nearby galaxies enable us to probe the way in which the chemical
elements are built up through the cosmic cycle of the birth, life,
and death of stars in systems at the present time. The study of similar
processes, but at much earlier cosmological epochs, can be carried out by
observing the chemical abundances of the elements in those galaxies
which can be observed in absorption against the continuum emission of
the most distant quasars. These absorption systems provide important
clues about the build up of chemical elements in systems which are only
about one fifth the present age of the Universe and so enable us to
track the chemical evolution of galaxies over long cosmological timescales.
The key to these studies is very high-precision, high-resolution
spectroscopy which can be carried out on much fainter stars, galaxies
and quasars than is possible with the present generation of telescopes."
-Dr. Malcolm S. Longair, Chair of the Gemini Board 1994-1995
What is the chemical enrichment history of the Galaxy and the Universe?
High resolution spectroscopy of the oldest stars in the Milky Way and
of gas clouds illuminated by distant quasars when the Universe was less
than one quarter its present age will enable us to determine how the
abundances of elements heavier than hydrogen and helium were built
up over time.
This program requires high-resolution spectroscopy of faint objects, which
in turn requires excellent imaging at optical wavelengths, high
throughput in the ultraviolet down to the atmospheric limit of
transmission, and the large light-gathering power of Gemini's 8-m
mirrors.
Image Credits: 1:KPNO
Ruth A. Kneale / web@gemini.edu / February 27, 1998