Deep learning-enabled size estimation of comets indicates a more dynamic early solar system [PDF]
Nature CommunicationsThe formation and evolution of the Solar System’s two major comet reservoirs, the Oort Cloud and the Scattered Disk, remain poorly constrained. Observations of comet flux imply a population ratio between these reservoirs that exceeds predictions from ...
Shunjing Zhao +4 more
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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
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Observational Characterization of Main-belt Comet and Candidate Main-belt Comet Nuclei
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
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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
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On Averaging Eccentric Orbits: Implications for the Long-term Thermal Evolution of Comets
The Astronomical Journal, 2023 One of the common approximations in long-term evolution studies of small bodies is the use of circular orbits averaging the actual eccentric ones, facilitating the coupling of processes with very different timescales, such as the orbital changes and the ...
Anastasios Gkotsinas +2 more
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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
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Disintegration of Long-period Comet C/2021 A1 (Leonard)
The Astronomical Journal, 2023 We present imaging observations of the disintegrating long-period comet C/2021 A1 (Leonard). High-resolution observations with the Hubble Space Telescope show no evidence for surviving fragments, and place a 3 σ upper limit on their possible radius of ...
David Jewitt +5 more
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The Gateway from Centaurs to Jupiter-family Comets: Thermal and Dynamical Evolution
The Astrophysical Journal, 2023 It was recently proposed that there exists a “gateway” in the orbital parameter space through which Centaurs transition to Jupiter-family comets (JFCs).
Aurélie Guilbert-Lepoutre +3 more
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Pits on Jupiter-family Comets and the Age of Cometary Surfaces
The Planetary Science Journal, 2023 Large and deep depressions, also known as pits, are observed at the surface of all Jupiter-family comets (JFCs) imaged by spacecraft missions. They offer the opportunity to glimpse the subsurface characteristics of comet nuclei and study the complex ...
Aurélie Guilbert-Lepoutre +6 more
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Development of an automated scoring system for plant comet assay
Frontiers in Genetics, 2015 In plants, an increasing interest for the Comet Assay was shown in the last decade and this versatile technique appears to be promising to detect the genotoxic effect of pollutants and to monitor the environment.
Bertrand Pourrut, Charles Homsy
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