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The Normal-incidence Extreme Ultraviolet Photometer (NExtUP) is a smallsat mission concept designed to measure the EUV radiation conditions of exoplanet host stars, and F-M type stars in general. EUV radiation is absorbed at high altitude in a planetary atmosphere, in the exosphere and upper thermosphere, where the gas can be readily heated to escape temperatures. EUV heating and ionization are the dominant atmospheric loss drivers during most of a planet’s life. There are only a handful of accurately measured EUV stellar fluxes, all dating from Extreme Ultraviolet Explorer (EUVE) observations in the ‘90s. Consequently, current models of stellar EUV emission are uncertain by more than an order of magnitude and dominate uncertainties in planetary atmospheric loss models. NExtUP will use periodic and aperiodic multilayers on off-axis parabolic mirrors and a prime focus microchannel plate detector to image stars in 5 bandpasses between 150 and 900°A down to flux limits two orders of magnitude lower than reached by EUVE. NExtUP may also accomplish a compelling array of secondary science goals, including using line-of-sight absorption measurements to understand the structure of the local interstellar medium, and imaging EUV emission from energetic processes on solar system objects at unprecedented spatial resolution. NExtUP is well within smallsat weight limits, requires no special orbital conditions, and would be flown on a spacecraft supplied by MOOG Industries. It draws on decades of mission heritage expertise at SAO and LASP, including similar instruments successfully launched and operated to observe the Sun.

The Gaia Catlogue of Nearby Stars is a catalogue of 331,312 objectsthat contains at least 92% of stars of stellar type M9 within 100pcof the Sun. We estimate that 9% of the stars in this catalogueprobably lie outside 100, pc, but when the distance probability function is used, a correct treatment of this contamination ispossible. We produced luminosity functions with a highsignal-to-noise ratio for the main-sequence stars, giants, and whitedwarfs. We examine in detail the Hyades cluster, the white dwarf population, and wide-binary systems and produced candidate lists forall three samples. We detected local manifestations of severalstreams, superclusters, and halo objects, in which we identified 12members of the Gaia Enceladus. We present the first direct parallaxes offive objects in multiple systems within 10pc of the Sun. In this poster we provide links to the outreach materials, data access and discussion groups of the GCNS project. &nbsp

Paul A. Scowen et al. -- 55 pags., 41 figs., 1 tab., We present the science cases and technological discussions that came from the workshop titled ¿Finding the ultraviolet (UV)-Visible Path Forward¿ held at NASA GSFC 2015 June 25-26. The material presented outlines the compelling science that can be enabled by a next generation space-based observatory dedicated for UV¿visible science, the technologies that are available to include in that observatory design, and the range of possible alternative launch approaches that could also enable some of the science. The recommendations to the Cosmic Origins Program Analysis Group from the workshop attendees on possible future development directions are outlined.