title: Pluto's interaction with its space environment: Solar wind, energetic particles, and dust.
abstract: The New Horizons spacecraft carried three instruments that measured the space environment near Pluto as it flew by on 14 July 2015. The Solar Wind Around Pluto (SWAP) instrument revealed an interaction region confined sunward of Pluto to within about 6 Pluto radii. The region's surprisingly small size is consistent with a reduced atmospheric escape rate, as well as a particularly high solar wind flux. Observations from the Pluto Energetic Particle Spectrometer Science Investigation (PEPSSI) instrument suggest that ions are accelerated and/or deflected around Pluto. In the wake of the interaction region, PEPSSI observed suprathermal particle fluxes equal to about 1/10 of the flux in the interplanetary medium and increasing with distance downstream. The Venetia Burney Student Dust Counter, which measures grains with radii larger than 1.4 micrometers, detected one candidate impact in ±5 days around New Horizons' closest approach, indicating an upper limit of <4.6 kilometers(-3) for the dust density in the Pluto system.
authors.affiliation: Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, CO 80600, USA. bagenal@colorado.edu.
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authors.affiliation: Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, CO 80600, USA.
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authors.affiliation: Southwest Research Institute, San Antonio, TX 78228, USA. University of Texas at San Antonio, San Antonio, TX 78249, USA.
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authors.affiliation: Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA.
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authors.affiliation: Southwest Research Institute, San Antonio, TX 78228, USA.
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authors.affiliation: Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA.
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authors.affiliation: Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA.
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authors.affiliation: Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA.
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authors.affiliation: Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA.
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authors.affiliation: Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA.
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authors.affiliation: Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, CO 80600, USA.
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authors.affiliation: Space Sciences Laboratory, University of California, Berkeley, CA 94720, USA.
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authors.affiliation: Johns Hopkins University, Baltimore, MD 21218, USA.
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authors.affiliation: Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, CO 80600, USA. Southwest Research Institute, Boulder, CO 80302, USA.
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authors.initials: JR
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authors.affiliation: Southwest Research Institute, San Antonio, TX 78228, USA.
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authors.affiliation: Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA.
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authors.affiliation: Southwest Research Institute, San Antonio, TX 78228, USA.
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authors.affiliation: NASA Ames Research Center, Moffett Field, CA 94035, USA.
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authors.affiliation: Southwest Research Institute, Boulder, CO 80302, USA.
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authors.affiliation: Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA.
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authors.affiliation: Southwest Research Institute, Boulder, CO 80302, USA.
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