The Importance of High Spatial and Appropriate Spectral Resolution Spectroscopy
Theodore Gull (NASA/GSFC/ASD)
Many diverse astronomical sources are resolved with diffraction-limited
large telescopes. Application of appropriate dispersion spectroscopy unveils much information
on the physics of these objects ranging from gamma ray bursters in host galaxies, star-formation
regions and central engines in nearby galaxies, structures in galactic nebulae, resolved binaries
with mass exchange, extended winds of massive stars, protoplanetary systems, and comets, asteroids
and planets within our own solar system. Active optics and interferometers coupled with spectrographs
can provide near-diffraction-limited spectroscopy from the ground but only longward of one micron.
Below one micron, and certainly below 6000A, we must turn to space-based large telescopes equipped
with spectrographs capable of providing spatially diffraction-limited spectroscopy of astronomical
sources. Examples will be presented from the HST/STIS, ground-based and other instruments on science
that has been accomplished. Suggestions will be made of what might be possible, and limitations thereof,
with future large monolithic, multiple mirror or interferometric telescopes equipped with spectrographs
that would be matched to the diffraction limit of the telescope.