The ultraviolet (92 – 320nm) and visible (320 – 1000nm) (UVV) regions of the spectrum contain a vital suite of diagnostic lines that can be used to study diverse astronomical objects and phenomena that shape and energize the interstellar medium. It is a critical spectral range for tracing the physics of interstellar and intergalactic gas, the ionization of nebulae, the properties of shocks, the atmospheres and winds of hot stars, energy transfer between galaxies and their surrounding environments, and the engines of active galactic nuclei. This spectral range contains diagnostics that measure gas density, electron temperature, and energy balance between various modes of cooling. It is an unfortunate truth that many, if not most, of these diagnostics can only be observed outside the Earth's atmosphere, requiring facilities in space. Space-based observations also provide access to diffraction-limited optical performance to achieve high spatial resolution — in the ultraviolet and visible bands the Rayleigh criterion yields resolutions unavailable even to JWST for moderate sized apertures. Such spatial resolutions cannot currently be achieved from the ground over wide fields, a capability that many science programs need for sampling and survey work.
In order to provide continuing access in the future, new space-based missions will be needed to provide the core imaging and spectroscopic information in this important part of the electromagnetic spectrum. The technology that enables such access has been a high priority in technology development plans that have been developed by both the Cosmic Origins Program Office and Astrophysics Division at NASA, but a holistic approach to considering what is needed for a long-term technology roadmap has not yet been discussed widely within the community.
This UVV Science Interest Group [SIG #2] will work with the COPAG to collect community input and define long-term Cosmic Origins science objectives of the UVV astronomy community that can be addressed by space-based observations. A primary goal for the SIG will be to identify a compelling suite of science cases to provide programmatic focal points that would justify and energize the community to support investment in next generation UVV missions or facilities. Through the SIG, the community will update the existing community-based roadmap for technology development for missions of different scales. The SIG will facilitate communication that will merge the needs and desires of the science community with the achievements and plans of the technology community. The SIG activities are expected to occur over an extended period of time, with results reported at periodic intervals (quarterly or semi-annually) to the COPAG Executive Committee and the Astrophysics Subcommittee. The SIG is open to any interested members of the community and we welcome any and all input.