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Solar sails enable missions to observe the solar environment from unique vantage points, such as sustained observations away from the Sun-Earth line; sub-L1 station keeping; high inclination solar orbits; Earth polar-sitting and polar-viewing observatories; fast transit missions to study heliosphere to interstellar medium transition, as well as missions of interest across a broad user community. Recent and planned demonstration missions make this technology ready for use on near-term science missions., Comment: Heliophysics 2050 White Paper

Advances in solar array, electric propulsion (EP), and power beaming technologies will very likely enable future missions to the ice giants (Uranus and Neptune) by spacecraft that are completely solar powered. Between 1959 and 2001 the power from solar arrays on missions in Earth orbit have increased by five orders of magnitude (from 1 W to >100,000 W). Simultaneously, the use of solar power has been extended to ever larger distances from the Sun. Three solar powered missions out to solar ranges of just beyond 5 au have now been developed and flown (Rosetta, Juno, and Lucy). At these distances, the solar insolation is roughly 25 times lower than that at 1 au. Solar-powered spacecraft to Saturn, where the solar insolation is 100 times lower than that at 1 au have recently been proposed to NASA. A solar-powered mission to Uranus would have to function where solar insolation is only 4 times lower than it is at Saturn. For Neptune, it would be 9 times lower than at Saturn. Three improvements in solar array technology are required to make this feasible. First, solar cells have to be able to function in the low-intensity, low-temperature (LILT) environment at Uranus and Neptune. Specially designed triple-junction solar cells have been tested at JPL under LILT conditions equivalent to the environment at 30 au have shown excellent performance (high efficiency and high fill factor). Second, the size of deployable solar arrays has to increase by one to two orders of magnitude relative to the current state of the art. Third, the areal density of solar arrays has to be reduced by an order of magnitude. This will most likely be accomplished through a combination of new thin-film solar cell technology like the Perovskite cells under development worldwide and the development of new deployable solar array structures such as those under investigation for solar-powered satellites. The solar insolation at Uranus and Neptune is 400 to 900 times lower, respectively, than it is at 1 au.

The Solar Gravitational Lens (SGL) allows for major brightness amplification ($\sim 10^{11}$ at wavelength of $1~\mu$m) and extreme angular resolution ($\sim10^{-10}$ arcsec) within a narrow field of view. A meter-class telescope, with a modest coronagraph to block solar light with 1e-6 suppression placed in the focal area of the SGL, can image an exoplanet at a distance of 30 parsec with few kilometer-scale resolution on its surface. Notably, spectroscopic broadband SNR is $\sim 10^{-6}$ in two weeks of integration time, providing this instrument with incredible remote sensing capabilities. A mission capable of exploiting the remarkable optical properties of the SGL allows for direct high-resolution imaging/spectroscopy of a potentially habitable exoplanet. Such missions could allow exploration of exoplanets relying on the SGL capabilities decades, if not centuries, earlier than possible with other extant technologies., Comment: A White Paper to the National Academy of Sciences Committee on an Exoplanet Science Strategy Call for Papers. 6 pages, 3 figures

The Solar Gravitational Lens (SGL) allows for major brightness amplification ($\sim 10^{11}$ at wavelength of $1~\mu$m) and extreme angular resolution ($\sim10^{-10}$ arcsec) within a narrow field of view. A meter-class telescope, with a modest coronagraph to block solar light with 1e-6 suppression placed in the focal area of the SGL, can image an exoplanet at a distance of 30 parsec with few kilometer-scale resolution on its surface. Notably, spectroscopic broadband SNR is $\sim 10^{-6}$ in two weeks of integration time, providing this instrument with incredible remote sensing capabilities. A mission capable of exploiting the remarkable optical properties of the SGL allows for direct high-resolution imaging/spectroscopy of a potentially habitable exoplanet. Such missions could allow exploration of exoplanets relying on the SGL capabilities decades, if not centuries, earlier than possible with other extant technologies., Comment: A White Paper to the National Academy of Sciences Committee on an Exoplanet Science Strategy Call for Papers. 6 pages, 3 figures

Cross-functional relationships during NPD projects have received considerable researchattention with an emphasis on achieving successful integration and avoiding harmfulconflict. The purpose of this paper is to develop and test an exploratory model examiningthe effects of managerial signalling behaviour, at top management and functional level,on conflict in cross-functional working relationships. Focussing on working relationshipbetween marketing managers and R&D managers in 184 new product developmentprojects in Australia this study examines the antecedents of conflict as reported by theR&D Manager. This study provides empirical support for the proposition that while topmanagement actions are useful in facilitating integration, the way a manager perceivestheir functional counterparts motives and intentions is a greater predictor of conflictwithin NPD projects.

The Advanced X-ray Timing Array (AXTAR) is a mission concept for X-ray timing of compact objects that combines very large collecting area, broadband spectral coverage, high time resolution, highly flexible scheduling, and an ability to respond promptly to time-critical targets of opportunity. It is optimized for submillisecond timing of bright Galactic X-ray sources in order to study phenomena at the natural time scales of neutron star surfaces and black hole event horizons, thus probing the physics of ultradense matter, strongly curved spacetimes, and intense magnetic fields. AXTAR's main instrument, the Large Area Timing Array (LATA) is a collimated instrument with 2-50 keV coverage and over 3 square meters effective area. The LATA is made up of an array of supermodules that house 2-mm thick silicon pixel detectors. AXTAR will provide a significant improvement in effective area (a factor of 7 at 4 keV and a factor of 36 at 30 keV) over the RXTE PCA. AXTAR will also carry a sensitive Sky Monitor (SM) that acts as a trigger for pointed observations of X-ray transients in addition to providing high duty cycle monitoring of the X-ray sky. We review the science goals and technical concept for AXTAR and present results from a preliminary mission design study., United States. National Aeronautics and Space Administration (NASA) (APRA program NNG10WF45I ), Naval Research Laboratory (John C. Stennis Space Center) (6.1 Base Program), MIT Kavli Instrumentation and Technology Development Fund

Cross-functional relationships during NPD projects have received considerable researchattention with an emphasis on achieving successful integration and avoiding harmfulconflict. The purpose of this paper is to develop and test an exploratory model examiningthe effects of managerial signalling behaviour, at top management and functional level,on conflict in cross-functional working relationships. Focussing on working relationshipbetween marketing managers and R&D managers in 184 new product developmentprojects in Australia this study examines the antecedents of conflict as reported by theR&D Manager. This study provides empirical support for the proposition that while topmanagement actions are useful in facilitating integration, the way a manager perceivestheir functional counterparts motives and intentions is a greater predictor of conflictwithin NPD projects.

The Advanced X-ray Timing Array (AXTAR) is a mission concept for X-ray timing of compact objects that combines very large collecting area, broadband spectral coverage, high time resolution, highly flexible scheduling, and an ability to respond promptly to time-critical targets of opportunity. It is optimized for submillisecond timing of bright Galactic X-ray sources in order to study phenomena at the natural time scales of neutron star surfaces and black hole event horizons, thus probing the physics of ultradense matter, strongly curved spacetimes, and intense magnetic fields. AXTAR's main instrument, the Large Area Timing Array (LATA) is a collimated instrument with 2-50 keV coverage and over 3 square meters effective area. The LATA is made up of an array of supermodules that house 2-mm thick silicon pixel detectors. AXTAR will provide a significant improvement in effective area (a factor of 7 at 4 keV and a factor of 36 at 30 keV) over the RXTE PCA. AXTAR will also carry a sensitive Sky Monitor (SM) that acts as a trigger for pointed observations of X-ray transients in addition to providing high duty cycle monitoring of the X-ray sky. We review the science goals and technical concept for AXTAR and present results from a preliminary mission design study., Comment: 19 pages, 10 figures, to be published in Space Telescopes and Instrumentation 2010: Ultraviolet to Gamma Ray, Proceedings of SPIE Volume 7732

The Advanced X-ray Timing Array (AXTAR) is a mission concept for X-ray timing of compact objects that combines very large collecting area, broadband spectral coverage, high time resolution, highly flexible scheduling, and an ability to respond promptly to time-critical targets of opportunity. It is optimized for submillisecond timing of bright Galactic X-ray sources in order to study phenomena at the natural time scales of neutron star surfaces and black hole event horizons, thus probing the physics of ultradense matter, strongly curved spacetimes, and intense magnetic fields. AXTAR's main instrument, the Large Area Timing Array (LATA) is a collimated instrument with 2-50 keV coverage and over 3 square meters effective area. The LATA is made up of an array of supermodules that house 2-mm thick silicon pixel detectors. AXTAR will provide a significant improvement in effective area (a factor of 7 at 4 keV and a factor of 36 at 30 keV) over the RXTE PCA. AXTAR will also carry a sensitive Sky Monitor (SM) that acts as a trigger for pointed observations of X-ray transients in addition to providing high duty cycle monitoring of the X-ray sky. We review the science goals and technical concept for AXTAR and present results from a preliminary mission design study., Comment: 19 pages, 10 figures, to be published in Space Telescopes and Instrumentation 2010: Ultraviolet to Gamma Ray, Proceedings of SPIE Volume 7732