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Observational Characterization of Main-belt Comet and Candidate Main-belt Comet Nuclei [PDF]
The Planetary Science Journal, 2023 We report observations of nine main-belt comets (MBCs) or candidate MBCs, most of which were obtained when the targets were apparently inactive. We find effective nucleus radii (assuming albedos of p _V = 0.05 ± 0.02) of r _n = (0.24 ± 0.05) km for 238P ...
Henry H. Hsieh +11 more
doaj +4 more sources
Thermal Shadows and Compositional Structure in Comet Nuclei [PDF]
The Astrophysical Journal, 2011 We use a fully 3-dimensional thermal evolution model to examine the effects of a non-uniform surface albedo on the subsurface thermal structure of comets.
Aurélie Guilbert-Lepoutre +12 more
core +4 more sources
Mid-infrared spectra of comet nuclei [PDF]
Icarus, 2017 Jovian Trojan D-type asteroids have mid-infrared emissivity features strikingly similar to comet comae, suggesting that they have the same compositions and that the surfaces of the Trojans are highly porous. However, a direct comparison between a comet and asteroid surface has not been possible due to the paucity of spectra of comet nuclei at mid ...
Michael S.P. Kelley +4 more
semanticscholar +6 more sources
The size distribution of Jupiter Family comet nuclei [PDF]
Monthly Notices of the Royal Astronomical Society, 2011 We present an updated cumulative size distribution (CSD) for Jupiter Family comet (JFC) nuclei, including a rigourous assessment of the uncertainty on the slope of the CSD. The CSD is expressed as a power law, N(>r_N) \propto r_N^{-q}, where r_N is the radius of the nuclei and q is the slope.
Snodgrass, Colin +3 more
semanticscholar +10 more sources
The Astrophysical Journal, 1990 The evolution of a comet nucleus is investigated, taking into account the crystallization process by which the gas trapped in the ice is released to flow through the porous ice matrix. The equations of conservation of the energy and of the masses of ice and gas are solved throughout the nucleus, to obtain the evolution of the temperature, gas pressure
D, Prialnik, A, Bar-Nun
openaire +3 more sources
Loss of the Surface Layers of Comet Nuclei [PDF]
Space Science Reviews, 2008 The Deep Impact observations of low thermal inertia for comet 9P/Tempel 1 are of profound importance for the observations to be made by the Rosetta spacecraft at comet 67P/Churyumov-Gerasimenko. While sub-surface sublimation is necessary to explain the observations, the depth at which this occurs is no more than 2–3 cm and possibly less.
Thomas, N., Alexander, C., Keller, H.
openaire +7 more sources
Origin and Early Evolution of Comet Nuclei [PDF]
, 2008 Foreword.- Origins of Cometary Materials.- Origin of Comet Nuclei and Dynamics.- Reservoir for Comet Material: Circumstellar Grains.- Interstellar Reservoirs of Cometary Matter.- Cometary Refractory Grains: Interstellar and Nebular Sources.- Dynamical Origin of Comets and Their Reservoirs.- Reservoirs for Comets: Compositional Differences Based on ...
H. Balsiger +4 more
openaire +2 more sources
Direct Simulation Monte Carlo Modeling of Ammonia in Comet C/2014 Q2 (Lovejoy)
The Astronomical Journal, 2023 Ammonia (NH _3 ), likely the most abundant nitrogen-bearing molecule in cometary ices followed by hydrogen cyanide, is believed to be stored in the nucleus predominantly as a parent ice.
Hideyo Kawakita +7 more
doaj +1 more source
Status of the COMET experiment [PDF]
EPJ Web of Conferences, 2023 The COMET (COherent Muon to Electron Transition) experiment, currently being built in Tokai, Japan, will search for the coherent neutrinoless transition of muons to electrons in the coulomb field of atomic nuclei.
Jansen Andreas
doaj +1 more source
TNO or Comet? The Search for Activity and Characterization of Distant Object 418993 (2009 MS9)
The Planetary Science Journal, 2023 The perihelion of the trans-Neptunian object (TNO) 2009 MS9 brings it close to the distance where some long-period comets are seen to become active.
Erica Bufanda +12 more
doaj +1 more source