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Publications (3)11.04 Total impact

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    ABSTRACT: The ALICE instrument is a lightweight (4.4 kg), low-power (4.4watt) imaging spectrograph aboard the New Horizons mission to the Pluto system and the Kuiper Belt. Its primary job is to determine the relative abundances of various species in Pluto’s atmosphere. ALICE will also be used to search for an atmosphere around Pluto’s moon, Charon, as well as the Kuiper Belt Objects (KBOs) that New Horizons is expected to fly by after Pluto-Charon, and it will make UV surface reflectivity measurements of all of these bodies, as well as of Pluto’s smaller moons Nix and Hydra. The instrument incorporates an off-axis telescope feeding a Rowland-circle spectrograph with a 520–1870Å spectral passband, a spectral point spread function of 3–6Å FWHM, and an instantaneous spatial field-of-view that is 6degrees long. Two different input apertures that feed the telescope allow for both airglow and solar occultation observations during the mission. The focal plane detector is an imaging microchannel plate (MCP) double delay-line detector with dual solar-blind opaque photocathodes (KBr and CsI) and a focal surface that matches the instrument’s 15-cm diameter Rowland-circle. In this paper, we describe the instrument in greater detail, including descriptions of its ground calibration and initial in flight performance. New Horizons launched on 19 January 2006.
    02/2009: pages 155-187;
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    ABSTRACT: The New Horizons instrument named Ralph is a visible/near infrared multi-spectral imager and a short wavelength infrared spectral imager. It is one of the core instruments on New Horizons, NASA's first mission to the Pluto/Charon system and the Kuiper Belt. Ralph combines panchromatic and color imaging capabilities with IR imaging spectroscopy. Its primary purpose is to map the surface geology and composition of these objects, but it will also be used for atmospheric studies and to map the surface temperature. It is a compact, low-mass (10.5 kg), power efficient (7.1 W peak), and robust instrument with good sensitivity and excellent imaging characteristics. Other than a door opened once in flight, it has no moving parts. These characteristics and its high degree of redundancy make Ralph ideally suited to this long-duration flyby reconnaissance mission.
    Space Science Reviews 10/2007; · 5.52 Impact Factor
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    ABSTRACT: The ALICE instrument is a lightweight (4.4 kg), low-power (4.4 W) imaging spectrograph that is planned to fly aboard the New Horizons mission to Pluto/Charon and the Kuiper Belt. Its primary job is to detect a variety of important atomic and molecular species in Pluto's atmosphere, and to determine their relative abundances as a function of altitude so that a complete picture of Pluto's atmospheric composition and structure can be determined for the first time. ALICE would also be used to search for an atmosphere around Pluto's moon, Charon, as well as the Kuiper Belt Objects (KBOs) that New Horizons hopes to fly by after Pluto-Charon. The New Horizons ALICE design, based on the Rosetta ALICE instrument design now en route to Comet 67P/ Churyumov-Gerasimenko aboard the European Space Agency's Rosetta spacecraft, incorporates an off-axis telescope feeding a Rowland-circle spectrograph with a 520-1870 Å spectral passband, a spectral point spread function of 3-6 Å FWHM, and an instantaneous spatial field-of-view of 6 degrees. Two separate input apertures that feed the telescope allow for both airglow and solar occultation observations during the mission. The focal plane camera is an imaging microchannel plate (MCP) double delay-line detector with dual solar-blind opaque photocathodes (KBr and CsI) and a focal surface that matches the 15-cm diameter Rowland-circle. Data taking modes include both histogram and pixel list exposures. We describe the scientific objectives of ALICE as well as the design, build, and environmental testing results of the flight model.