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Title - The pristine interior of comet 67P revealed by the combined Aswan outburst and cliff collapse
By - Pajola et al, 2017
Summary - .
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Title - Refractory species in the neutral gas coma of comet 67P
By - Martin Rubin et al, 2022
Summary - When the comet was at a heliocentric distance of 3 AU before perihelion, DFMS detected sodium, silicon, potassium, calcium & iron in atomic form.
Title - Refractory elements in the gas phase for comet 67P
By - Martin Rubin et al, 2021
Summary -
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Title - The dust size distribution in comet 67P and comparison with other small bodies
By - Giovanna Rinaldi et al, 2022
Summary - .
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Title - Evolution of the smooth terrains on comet 67P
By - Alexander Hayes et al, 2022
Summary - .
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Title - Cometocentric coordinates of the tail axis of comet 67P
By - Ibragimov, 2022
Summary - .
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Title - Variability in the elemental composition of the dust particles of 67P
By - Ines Sansberro et al, 2022
Summary - .
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Title - The Astrobiological Heritage of the Rosetta Space Mission: New Ingredients for a Prebiotic Soup
By - Herve Cottin, 2022
Summary - .
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Title - Distribution of dust in the innermost comae of comets
By - Nicolas Thomas et al, 2022
Summary - .
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By - Alejandra Traspas Muina et al, 2022
Summary - .
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Title - Albedo variegation on Comet 67P
By - Bjorn Davidsson et al, Sept 2022
Summary - .
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Title - Main results from the ISSI International Team "Characterization of 67P cometary activity"
By - Andrea Longobardo et al, July 2022
Summary - .
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Title - Variability in the elemental composition of the dust particles of 67P
By - Inès Sansberro et al, July 2022
Summary - .
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Title - Flying through cometary jets with the Rosetta spacecraft
By - Brais Gesto Herrera. Dec 2022
Summary - .
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Title - Near-perihelion activity of comet 67P. A first attempt of non-static analysis
By - Yu Skorov et al, 2020
Summary - Thermophysical models with a uniform and static ice free layer do not reproduce the observed steep water production rates of 67P near perihelion. Widely used thermophysical models based on a static dust layer on top of the icy/refractory matrix are poorly consistent with these observations. Accelerated gas activity is explained by the deeper penetration of the heat wave during polar day (no sunset), which can activate sublimation through thicker inert dust layers. This can also lead to removal of thicker dust layers and consequently to an expansion of the active area. According to published results, the thermal conductivity of comet 67P is uncertain by a factor of 100.
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Title - The changing temperature of the nucleus of comet 67P induced by morphological and seasonal effects
By - Tosi et al, 2019
Summary - "Over longer periods, VIRTIS-derived temperature values reveal seasonal changes driven by decreasing heliocentric distance combined with an increasing abundance of ice within the uppermost centimeter-thick layer, which implies the possibility of having a largely pristine nucleus interior already in the shallow subsurface."
"abundance of ice within the uppermost centimeter-thick layer" - this physics defying expectation seems ignorant of the fact that even -123C is too warm for ice to exist on surface or even meters below it. Are comet scientists weak in temperature physics ?
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Title - Rosetta Views Comet 67P Making Its Closest Approach to the Sun
By - European Space Agency (ESA) 2015
Summary - Rosetta’s measurements suggest the comet is spewing up to 300 kg of water vapor – roughly the equivalent of two bathtubs – every second. This is a 1000 times more than what was observed this time last year (2014) when Rosetta first approached the comet. Then, it recorded an outflow rate of just 300 g per second, equivalent to 2 small glasses of water.
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Title - Rosetta’s big day in the sun
By - European Space Agency (ESA), Aug 2015
Summary - See extra notes.
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Title - Icy surprises at Rosetta’s comet
By - ESA, Nov 2016
Summary - See extra notes.
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Title - Rosetta’s last words : Science descending to a comet
By - ESA, Dec 2016
Summary - See extra notes.
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Title - 137 page book - Analysis of MIRO/Rosetta Data
By - David Marshall, 2018
Summary - Dissertation.
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Title - The Aswan cliff collapse on comet 67P
By - Pajola et al, 2017
Summary - Useful info on temperature, plumes, fractures.
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Title - The pristine interior of comet 67P revealed by the combined Aswan outburst and cliff collapse
By - Pajola et al, 2017
Summary - Here we report the first unambiguous link between an outburst and a cliff collapse on a comet. We establish a new dust-plume formation mechanism that does not necessarily require the breakup of pressurized crust or the presence of supervolatile material, as suggested by previous studies7. Moreover, the collapse revealed the fresh icy interior of the comet.
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Title - Surface changes on comet 67P suggest a more active past
By - Ramy El-Maarry et al, 2017
Summary - .
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Title - How Comet 67P’s Face Changed During Its Trip Around the Sun
By - New York Times, 2017
Summary - Refers to the above two papers 22 & 23.
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Title - Crumbling comet? The great debate about whether Rosetta rock 67P is breaking apart
By - The Conversation website, 2017
Summary - Useful info on rocky comet, missing ice, cliff collapse.
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Title - Comet 67-P farted just as Rosetta probe flew through the gas plume
By - The Register website, 2017
Summary - "Things get interesting when the boffins consider the ratio of dust to water ice in the plume, because there was rather more dust than ice. Evaporation of ice alone can't explain the energy required to shoot lots of dust up into space, leaving astroboffins wondering what lurked beneath the surface of 67P that could power a plume".
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By - Fornasier et al, 2015
Summary - .
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By - Paul Feldman et al, 2015
Summary - .
News - Nature (Ultraviolet close-up reveals comet surprise)
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Title - Coma composition of comet 67P/Churyumov-Gerasimenko from radio-wave spectroscopy
By - Biver et al, 2023
Summary - .
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Title - On the Origin and Evolution of the Material in comet 67P
By - Martin Rubin et al, 2020
Summary - The emerging picture after Rosetta is that at least part of the volatile material was formed before the solar system and that cometary nuclei agglomerated over a wide range of heliocentric distances, different from where they are found today. Deviations from bulk solar system abundances indicate that the material was not fully homogenized at the location of comet formation, despite the radial mixing implied by the Stardust results. Post-formation evolution of the material might play an important role, which further complicates the picture.
It seems unlikely that comets from the Kuiper belt and beyond were the major source for the water on Earth. Instead, the results suggest that the D/H ratio reflects the formation location of comets rather than where they are found today: comets formed over a wide range of heliocentric distances and were relocated afterwards. Both lobes of 67P/C-G share the same D/H ratio within error bars.
The refractories in other comets, including the returned samples from comet Wild 2, contain thermally processed material from the inner solar system with only small amounts of presolar material. Thus, radial mixing occurs, but the protoplanetary disk remains only partially homogenized. Therefore, the isotopic and possibly also elemental and molecular abundances in at least the icy phase at the location of the comet’s formation differed from bulk solar system.
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Title - Quantifying Morphological Changes and Sediment Transport Pathways on Comet 67P
By - Barrington et al, 2023
Summary - Sediment transport appears linked to the location of most direct sunlight on the comet's surface and does not occur on the top of the comet's lobes. Note : Authors believe in the pseudoscience of sublimation driven comet activity.
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Title - The dust-to-ices ratio in comet 67P and Kuiper belt objects
By - Fulle et al, 2017
Summary - .
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Title - The diurnal cycle of water ice on comet 67P
By - De Sanctis et al, 2015
Summary - Observations of cometary nuclei have revealed a very limited amount of surface water ice, which is insufficient to explain the observed water outgassing. This was clearly demonstrated on comet 9P/Tempel 1, where the dust jets (driven by volatiles) were only partially correlated with the exposed ice regions. The observations of comet 67P have revealed that activity has a diurnal variation in intensity arising, from changing insolation conditions. It was previously concluded that water vapour was generated in ice-rich subsurface layers, with a transport mechanism linked to solar illumination but that has not hitherto been observed. Periodic condensations of water vapour very close to, or on, the surface were suggested to explain short-lived outbursts seen near sunrise on comet 9P/Tempel 1. Here we report observations of water ice on the surface of comet 67P, appearing and disappearing in a cyclic pattern that follows local illumination conditions, providing a source of localized activity. This water cycle appears to be an important process in the evolution of the comet, leading to cyclical modification of the relative abundance of water ice on its surface.
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Title - An orbital water-ice cycle on comet 67P from colour changes
By - Gianrico Filacchione et al, 2020
Summary - Solar heating of a cometary surface provides the energy necessary to sustain gaseous activity, through which dust is removed (bogus claim). The environment around an active nucleus is populated by dust grains with complex and variegated shapes, lifted and diffused by gases freed from the sublimation of surface ices (bogus claim). The visible colour of dust particles is highly variable: carbonaceous organic material-rich grains appear red while magnesium silicate-rich and water-ice-rich grains appear blue, with some dependence on grain size distribution, viewing geometry, activity level and comet family type. We know that local colour changes are associated with grain size variations, such as in the bluer jets made of sub-micrometre grains on comet Hale–Bopp15 or in the fragmented grains in the coma of C/1999 S4 (LINEAR). Apart from grain size, composition also influences the coma’s colour response, because transparent volatiles can introduce a substantial blueing in scattered light, as observed in the dust particles ejected after the collision of the Deep Impact probe with comet 9P/Tempel 1. Here we report observations of two opposite seasonal colour cycles in the coma and on the surface of comet 67P through its perihelion passage. Spectral analysis indicates an enrichment of sub-micrometre grains made of organic material and amorphous carbon in the coma, causing reddening during the passage. At the same time, the progressive removal of dust from the nucleus causes the exposure of more pristine and bluish icy layers on the surface (bogus claim, ice below surface defies thermal physics). Far from the Sun, we find that the abundance of water ice on the nucleus is reduced owing to redeposition of dust and dehydration of the surface layer while the coma becomes less red.
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