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  • 1
    Publication Date: 2018-06-28
    Description: The development of onboard autonomy capability is the key to a set of vastly important strategic technical challenges facing NASA: increased efficiency in the return of quality science products, reduction of mission costs, and the launching of a new era of solar system exploration characterized by sustained presence, in-situ science investigations and missions accomplished via multiple, coordinated space platforms. Autonomy is a central capability for enabling missions that inherently must be accomplished without the benefit of ongoing ground support. This constraint may arise due to control challenges, e.g., small-body rendezvous and precision landing, or may arise due to mission planning challenges based in the difficulty of modeling the planetary environment coupled with the difficulty or impossibility of communications during critical or extended periods. A sophisticated Mars rover, a comet lander, a Europan under-ice explorer, and a Titan aerobot are examples of missions, some unprecedented, which typify these challenges. This paper describes the set of NASA missions that aim to utilize autonomy and recent developments in the creation of space platform autonomy capabilities at NASA.
    Keywords: Lunar and Planetary Science and Exploration
    Type: Intelligent Systems for Aeronautics; 4-1 - 4-12; RTO-EN-022
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  • 2
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    In:  Other Sources
    Publication Date: 2018-06-08
    Keywords: Lunar and Planetary Science and Exploration
    Type: AAAI 02 National Conference; Edmonton, Alberta; Canada
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  • 3
    Publication Date: 2019-07-13
    Description: [1] Near-infrared spectra taken in a limb-viewing geometry by the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) on board the Mars Reconnaissance Orbiter provide a useful tool for probing atmospheric structure. Specifically, the observed radiance as a function of wavelength and height above the limb enables the vertical distribution of both dust and water ice aerosols to be retrieved. More than a dozen sets of CRISM limb observations have been taken so far providing pole-to-pole cross sections, spanning more than a full Martian year. Radiative transfer modeling is used to model the observations taking into account multiple scattering from aerosols and the spherical geometry of the limb observations. Both dust and water ice vertical profiles often show a significant vertical structure for nearly all seasons and latitudes that is not consistent with the well-mixed or Conrath-v assumptions that have often been used in the past for describing aerosol vertical profiles for retrieval and modeling purposes. Significant variations are seen in the retrieved vertical profiles of dust and water ice aerosol as a function of season. Dust typically extends to higher altitudes (approx. 40-50km) during the perihelion season than during the aphelion season (〈20km), and the Hellas region consistently shows more dust mixed to higher altitudes than other locations. Detached water ice clouds are common, and water ice aerosols are observed to cap the dust layer in all seasons.
    Keywords: Lunar and Planetary Science and Exploration
    Type: GSFC-E-DAA-TN9104 , Journal of Geophysical Research - Planets; 118; 2; 321-334
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  • 4
    Publication Date: 2019-07-13
    Description: The Martian polar night distribution of 1.27 micron (0-0) band emission from O2 singlet delta [O2(1Delta(sub g))] is determined from an extensive set of Mars Reconnaissance Orbiter (MRO) Compact Reconnaissance Imaging Spectral Mapping (CRISM) limb scans observed over a wide range of Mars seasons, high latitudes, local times, and longitudes between 2009 and 2011. This polar nightglow reflects meridional transport and winter polar descent of atomic oxygen produced from CO2 photodissociation. A distinct peak in 1.27 micron nightglow appears prominently over 70-90NS latitudes at 40-60 km altitudes, as retrieved for over 100 vertical profiles of O2(1Delta(sub g)) 1.27 micron volume emission rates (VER). We also present the first detection of much (x80+/-20) weaker 1.58 micron (0-1) band emission from Mars O2(1Delta(sub g)). Co-located polar night CRISM O2(1Delta(sub g)) and Mars Climate Sounder (MCS) (McCleese et al., 2008) temperature profiles are compared to the same profiles as simulated by the Laboratoire de Mtorologie Dynamique (LMD) general circulation/photochemical model (e.g., Lefvre et al., 2004). Both standard and interactive aerosol LMD simulations (Madeleine et al., 2011a) underproduce CRISM O2(1Delta(sub g)) total emission rates by 40%, due to inadequate transport of atomic oxygen to the winter polar emission regions. Incorporation of interactive cloud radiative forcing on the global circulation leads to distinct but insufficient improvements in modeled polar O2(1Delta(sub g)) and temperatures. The observed and modeled anti-correlations between temperatures and 1.27 mm band VER reflect the temperature dependence of the rate coefficient for O2(1Delta(sub g)) formation, as provided in Roble (1995).
    Keywords: Lunar and Planetary Science and Exploration
    Type: GSFC-E-DAA-TN8903 , Journal of Geophysical Research - Planets; 117; E11; E00J10
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