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This review concentrates on observations that will be performed with the new generation of space ultraviolet spectrographs, especially the Goddard High Resolution Spectrograph on the Hubble Space Telescope. The broad astrophysical problems are outlined and the needs for specific laboratory data are placed in context. The existing laboratory data will need to be improved significantly to provide both wavelengths accurate to λ/Δλ ≥ 106 for resonance transitions and oscillator strengths accurate to better than 10%. In addition, weak lines of ions of rare heavy elements can now be studied with S/N ratios better than 100, and the existing databases for these species will need expansion. Molecular data will also be needed for a wide range of applications.

The high resolution spectrograph on HST, with resolving powers up to 94000 or 3.2 km s−1, is giving us a new look at interstellar absorption lines in the range 1090 to 3350 A. The high signal-to-noise ratios possible with the digicon detectors provide precise line profiles suitable for studying individual velocity components.

Determining which stars give rise to supernovae (SNe) is key to SN research and stellar evolution studies. Without knowledge of SN progenitors, many of the conclusions and inferences made about the connection between SNe and important problems in astrophysics stand on precarious ground. The main obstacle is that a SN leaves few traces of the star that exploded.

The Great Observatories Origins Deep Survey (GOODS) is designed to gather the best and deepest multiwavelength data for studying the formation and evolution of galaxies and active galactic nuclei, the distribution of dark and luminous matter at high redshift, the cosmological parameters from distant supernovae, and the extragalactic background light. The program uses the most powerful space- and ground-based telescopes to cover two fields, each 10'x16', centered on the Hubble Deep Field North and the Chandra Deep Field South, already the sites of extensive observations from X-ray through radio wavelengths. GOODS incorporates 3.6-24 micron observations from a SIRTF Legacy Program, four-band ACS imaging from an HST Treasury Program, and extensive new ground-based imaging and spectroscopy. GOODS data products will be made available on a rapid time-scale, enabling community research on a wide variety of topics. Here we describe the project, emphasizing its application for studying the mass assembly history of galaxies.