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Dust and gas emission from cometary nuclei: the case of comet 67P/Churyumov–Gerasimenko
Advances in Physics: X, 2018 Comets display with decreasing solar distance an increased emission of gas and dust particles, leading to the formation of the coma and tail. Spacecraft missions provide insight into the temporal and spatial variations of the dust and gas sources located
Tobias Kramer +4 more
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3.5 The Dust Coma of Comets [PDF]
International Astronomical Union Colloquium, 1976 AbstractAnalytical expressions for the dust entrainment in the limits of low and high gas production from cometary nuclei are derived. The resulting volume density is used to evaluate the dust production of Comets Encke and Kohoutek from IR-measurements. It is predicted, that the dust in solar direction was diffuse for Comet Kohoutek during approach to
K.W. Michel, T. Nishimura
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Frontiers in Physics, 2020 In this work, we present results that simultaneously constrain the dust size distribution, dust-to-gas ratio, fraction of dust re-deposition, and total mass production rates for comet 67P/Churyumov-Gerasimenko.
Raphael Marschall +7 more
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Dust Outburst Dynamics and Hazard Assessment for Close Spacecraft–Comet Encounters
The Planetary Science Journal, 2021 Using the gas drag by sublimating cometary surface ices for the acceleration of dust particles and deceleration by the gravity field of the nucleus combined with basic laws of mechanics, the sizes, velocities, and number densities of escaping particles ...
Uwe Fink +6 more
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Unusual polarimetric properties for interstellar comet 2I/Borisov
Nature Communications, 2021 Polarimetry provides information about physical characteristics of cometary dust. Here, the authors show that the polarization of interstellar comet 2I/Borisov exceeds the typical values for comets, and this together with its polarimetrically homogenous ...
S. Bagnulo +8 more
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CO and CO2 Productions Rates of Comets Observed by NEOWISE within Year 1 of the Reactivated Mission
The Planetary Science Journal, 2023 We report on the observed fluxes of the comets detected by NEOWISE during the first year of operations after the spacecraft’s reactivation. The sample included 57 comets.
Adeline Gicquel +4 more
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Models of Rosetta/OSIRIS 67P Dust Coma Phase Function [PDF]
The Astronomical Journal, 2018 Abstract The phase function of the dust coma of comet 67P has been determined from Rosetta/OSIRIS images. This function shows a deep minimum at phase angles near 100°, and a strong backscattering enhancement. These two properties cannot be reproduced by regular models of cometary dust, most of them based on wavelength-sized and randomly ...
F. Moreno +41 more
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Optical Imaging Polarimetry of Comet 21P/Giacobini–Zinner during Its 2018 Apparition
The Planetary Science Journal, 2023 We conducted polarimetric observations of comet 21P/Giacobini–Zinner in the optical wavelength region using the polarimetric imager PICO equipped with the 50 cm telescope for Public Outreach at the Mitaka Campus of the National Astronomical Observatory ...
Yoshiharu Shinnaka +4 more
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The Dust in the Coma of Comet Halley [PDF]
International Astronomical Union Colloquium, 1991 Abstract The interstellar dust model of comets is numerically worked out to satisfy several basic constraints provided by observations of comet Halley and to derive the porosity of coma dust. The observational constraints are: (1) the strengths of the 3.4 μm and 9.7 μm emission bands; (2) the relative amount of silicates to organic materials; (3 ...
Joniek I. Hage, J. Mayo Greenberg
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Comet P/2021 HS (PANSTARRS) and the Challenge of Detecting Low-activity Comets
The Planetary Science Journal, 2023 Jupiter-family comet (JFC) P/2021 HS (PANSTARRS) only exhibits a coma within a few weeks of its perihelion passage at 0.8 au, which is atypical for a comet.
Quanzhi Ye +10 more
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