Results 41 to 50 of about 902 (203)

Coma Abundances of Volatiles at Small Heliocentric Distances: Compositional Measurements of Long-period Comet C/2020 S3 (Erasmus)

open access: yesThe Astronomical Journal, 2023
We report production rates of H _2 O and nine trace molecules (C _2 H _6 , CH _4 , H _2 CO, CH _3 OH, HCN, NH _3 , C _2 H _2 , OCS, and CO) in long-period comet C/2020 S3 (Erasmus) using the high-resolution, cross-dispersed infrared spectrograph (iSHELL)
Chemeda Ejeta   +11 more
doaj   +1 more source

Comet P/2021 HS (PANSTARRS) and the Challenge of Detecting Low-activity Comets

open access: yesThe 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
doaj   +1 more source

Recurring Activity Discovered on Quasi-Hilda 2009 DQ118

open access: yesThe Astrophysical Journal Letters, 2023
We have discovered two epochs of activity on quasi-Hilda 2009 DQ _118 . Small bodies that display comet-like activity, such as active asteroids and active quasi-Hildas, are important for understanding the distribution of water and other volatiles ...
William J. Oldroyd   +12 more
doaj   +1 more source

Physical Properties of Frozen Volatiles—Their Relevance to the Study of Comet Nuclei [PDF]

open access: yesInternational Astronomical Union Colloquium, 1989
AbstractThe structural and thermodynamical properties of water ice and ice mixtures containing CO, CO2, CH4, and NH3 are thought to be important for the evolution of cometary nuclei. Based on recent laboratory studies performed by several groups, an overview is given of the properties of various ices condensed at low temperatures and of their evolution
openaire   +1 more source

The Effects of Early Collisional Evolution on Amorphous Water Ice Bodies

open access: yesThe Planetary Science Journal, 2023
Conditions in the outer protoplanetary disk during solar system formation were thought to be favorable for the formation of amorphous water ice (AWI), a glassy phase of water ice.
Jordan K. Steckloff   +2 more
doaj   +1 more source

The Impact of Genetic Polymorphisms on Genotoxicity (DNA Damage) Among Children Exposed to Environmental Mutagens: A Systematic Review

open access: yesJournal of Applied Toxicology, EarlyView.
ABSTRACT Children, as a particularly vulnerable group, are more susceptible to these mutagens due to their developing immune systems, higher physiological vulnerability, and increased exposure through behaviors like outdoor play and hand‐to‐mouth activities. This review aims to investigate the relationship between these environmental exposures, genetic
Thiago Guedes Pinto   +7 more
wiley   +1 more source

Rheological Characterization and Multi‐Regime Viscosity Modeling of Diluted Polyethylene Mixtures

open access: yesPolymer Engineering &Science, EarlyView.
This study maps the flow behavior of low‐density polyethylene in a recycling solvent from dilute solutions to entangled melts. By integrating time–concentration and time–temperature superposition, and coupling three complementary rheometry methods, a unified semiempirical model accurately predicts steady‐shear viscosity over nine decades of viscosity ...
Johannes Krug   +7 more
wiley   +1 more source

From Flybys to Sample Return: A Review of Space Probes and Robotic Sampling Technologies for Small Bodies

open access: yesJournal of Field Robotics, EarlyView.
ABSTRACT As a crucial puzzle piece of deep space exploration, exploring small bodies can provide significant scientific insights and valuable mineral resources. Unlike missions to the Moon and Mars, small‐body missions pose distinct technical challenges, including communication delays, weak gravity, and uncertain environments. This paper reviews a full
Xin Zhang   +3 more
wiley   +1 more source

Noble gases and nitrogen in material from asteroid Bennu

open access: yesMeteoritics &Planetary Science, EarlyView.
Abstract We report the elemental and isotopic abundances of all stable noble gases (helium, neon, argon, krypton, and xenon) in eight particles from asteroid Bennu returned by NASA's OSIRIS‐REx mission. We also report nitrogen abundances and isotopic ratios that were analyzed alongside neon and argon in four additional Bennu particles.
B. Marty   +7 more
wiley   +1 more source

Parent Volatile Outgassing Associations in Cometary Nuclei: Synthesizing Rosetta Measurements and Ground-based Observations

open access: yesThe Planetary Science Journal
Comets, as remnants of the solar system’s formation, vary in volatile-refractory content. In situ comet studies, such as the Rosetta mission to 67P/Churyumov–Gerasimenko, provide detailed volatile composition insights, while ground-based studies offer ...
Mohammad Saki   +7 more
doaj   +1 more source

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