Results 71 to 80 of about 2,512 (186)
Spatial Distribution of H2O+ Ions in the Inner Coma of C/2014 Q2 (Lovejoy)
The Astrophysical JournalNeutral molecules that sublimate from cometary ices (mainly water at ∼1 au from the Sun) are ionized due to solar extreme-ultraviolet radiation and collisions with highly energetic electrons.
Hideyo Kawakita +2 more
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Photometric and spectroscopic monitoring of the outbursting Halley-type comet 12P/Pons-Brooks
Astronomy & AstrophysicsContext. Comet 12P/Pons-Brooks is a Halley-type comet known for its outbursting activity during its previous perihelia in 1883 and 1953. Its strong activity and favourable observing geometry gave a great opportunity to study this outburst-prone comet ...
Vander Donckt M. +8 more
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The Planetary Science JournalHydrogen sulfide (H _2 S) is the fifth most abundant molecule observed in the coma of comet 67P/Churyumov–Gerasimenko (67P). Prior to its incorporation into cometary materials, H _2 S likely underwent ultraviolet (UV) radiation exposure, which is thought
Ahmed Mahjoub +4 more
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The Volatile Composition and Activity Evolution of Main-belt Comet 358P/PANSTARRS
The Planetary Science JournalWe report the detection of water vapor associated with main-belt comet 358P/PANSTARRS on UT 2024 January 8–9 using the NIRSPEC instrument on board JWST.
Henry H. Hsieh +19 more
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Optical and Near-infrared Spectroscopy of the Outbursting Comet 12P/Pons-Brooks
The Astrophysical JournalWe present optical and near-infrared (NIR) observations of the outbursting, Halley-type comet 12P/Pons-Brooks (12P). Three NIR spectra were obtained during two outbursts in 2023 October and November, with the 3 m Infrared Telescope Facility and the ...
Ruining Zhao +6 more
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The activity characteristics and mechanisms of long-period comets
Earth and Planetary PhysicsComets are small celestial bodies orbiting around the Sun. They are remnants left over from the formation of the solar system; their interiors store original material of the planetary disk within the solar system. They are thus "fossils" for studying the
YingQi Wu +3 more
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Brightness Behavior of Distant Oort Cloud Comets
The Planetary Science JournalDynamically new comets provide important insights into the conditions of the presolar nebula and its evolution, as they are believed to have experienced minimal solar heating before their discovery.
Carrie E. Holt +17 more
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Keck and Gemini Characterization of Hayabusa2# Rendezvous Target 1998 KY26
The Astronomical JournalNear-Earth object (NEO) 1998 KY _26 is a target of the Hayabusa2# spacecraft, which it will rendezvous with in 2031 July. The asteroid has been noted to rotate rapidly and has a large out-of-plane nongravitational acceleration.
Bryce T. Bolin +9 more
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Simple Analytical Models of Grain Fragmentation in a Cometary Coma
The Astrophysical JournalMeasurements by the dual Langmuir Probe (LAP) on board Rosetta in the inner coma of comet 67P/Churyumov–Gerasimenko revealed an unexpected ∼50% level of attenuation of the impinging solar extreme-ultraviolet (EUV) radiation while the comet was near ...
E. Vigren +3 more
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The Coma Cluster as a Spherical Inhomogeneity in Relativistic Dust
The Astrophysical Journal, 1969 Dynamical model for spherical inhomogeneity in mean mass density of universe to predict velocity dispersion observed for Coma ...
openaire +1 more source