Results 51 to 60 of about 793,175 (240)

Interstellar polarization and grain alignment: the role of iron and silicon

, 2012
We compiled the polarimetric data for a sample of lines of sight with known abundances of Mg, Si, and Fe. We correlated the degree of interstellar polarization $P$ and polarization efficiency (the ratio of $P$ to the colour excess $E(B-V)$ or extinction $
Abbas, Andersson, Andersson, Andersson, Andersson, Asplund, Belley, Das, Davis, Djouadi, Draine, Draine, Duley, Efimov, Elias, Fitzpatrick, Ghosh, H. K. Das, Harries, Heiles, Il’in, Jones, Kim, Kimura, Kimura, Kocifaj, Krauß, Larson, Lazarian, Lazarian, Leroy, M. S. Prokopjeva, Marraco, Martin, Mathis, Matsumura, McDavid, Michel, Min, Molster, N. V. Voshchinnikov, Niyogi, Oudmaijer, Patriarchi, Poeckert, Purcell, Roche, Serkowski, Sorrell, Sorrell, Sturm, Th. Henning, Valencic, van Breemen, Vega, Vink, Voshchinnikov, Voshchinnikov, Voshchinnikov, Voshchinnikov, Wegner, Wegner, Weingartner, Weitenbeck, Whittet, Whittet   +65 more
core   +1 more source

Dust in the Local Interstellar Wind [PDF]

, 1999
The gas-to-dust mass ratios found for interstellar dust within the Solar System, versus values determined astronomically for the cloud around the Solar System, suggest that large and small interstellar grains have separate histories, and that large ...
Dorschner, J. M., Frisch, P. C., Geiss, J., Greenberg, J. M., Grün, E., Hoppe, P., Jones, A. P., Krätschmer, W., Landgraf, M., Linde, T. J., Morfill, G. E., Reach, W. T., Slavin, J. D., Svestka, J., Witt, A. N., Zank, G. P.   +15 more
core   +2 more sources

Hydro-chemical study of the evolution of interstellar pre-biotic molecules during the collapse of molecular clouds

, 2012
One of the stumbling blocks for studying the evolution of interstellar molecules is the lack of adequate knowledge of the rate co-efficients of various reactions which take place in the Interstellar medium and molecular clouds.
Ankan Das, Boogert, Chakrabarti, Chakrabarti, Chakrabarti, Cuppen, Das, Fuente, Gibb, Guelin, Ioppolo, Kuan, Liton Majumdar, Sandip K. Chakrabarti, Snyder, Sonali Chakrabarti, Woon   +16 more
core   +1 more source

Charge State Influence on Stability and Isomerism in Dehydrogenated PAHs: Insights from Anthracene, Acridine, and Phenazine

ChemPhysChem, Volume 26, Issue 6, March 15, 2025.
The ionization of anthracene, acridine, and phenazine has been explored, along with the removal of one and two hydrogen atoms, to provide valuable information for astrochemists and to understand the behavior of the resulting structures and their electronic reorganization. Abstract In this study, we systematically explored the stability and isomerism of
Khaldia Zghida, Farouk Hamza Reguig, Manuel Alcamí, Al Mokhtar Lamsabhi   +3 more
wiley   +1 more source

Generalized Te([O iii])–Te(He i) Discrepancies in Ionized Nebulae: Possible Evidence of Case B Deviations and Temperature Inhomogeneities

The Astrophysical Journal
The physics of recombination lines in the He i singlet system is expected to be relatively simple, supported by accurate atomic models. We examine the intensities of He i singlets λ 3614,  λ 3965,  λ 5016,  λ 6678, and  λ 7281 and the triplet He i λ 5876
J. E. Méndez-Delgado, E. D. Skillman, E. Aver, C. Morisset, C. Esteban, J. García-Rojas, K. Kreckel, N. S. J. Rogers, F. F. Rosales-Ortega, K. Z. Arellano-Córdova, S. R. Flury, E. Reyes-Rodríguez, M. Orte-García, S. Tan   +13 more
doaj   +1 more source

Out There No One Has a Right to Die

Bioethics, EarlyView.
ABSTRACT The eventual goal of space exploration is to colonize exoplanets and their moons outside our solar system. This is a dangerous and immoral endeavour. The extraterrestrial life forms encountered would be hostile, vulnerable or both, and the descendants of the original pioneers would be involuntarily exposed to hazardous conditions and ...
Matti Häyry
wiley   +1 more source

Determining the Methanol Deuteration in the Disk Around V883 Orionis with Laboratory Measured Spectroscopy

The Astronomical Journal
Deuterium fractionation, as studied through mono-deuterated methanol, is frequently used as a diagnostic tool to trace the physical conditions and chemical evolution of interstellar sources. This study investigates methanol deuteration in the disk around
Shaoshan Zeng, Jae-Hong Jeong, Takahiro Oyama, Jeong-Eun Lee, Yao-Lun Yang, Nami Sakai   +5 more
doaj   +1 more source

Abundances in Diffuse Interstellar Clouds [PDF]

Highlights of Astronomy, 1980
Interstellar clouds are concentrations of cold (T ≲ 100 K) neutral gas (cf. Spitzer 1978) which are immersed within an intercloud medium. It is worthwhile to distinguish between diffuse clouds (roughly those with E[B-V] ≳ 0.5) and dark clouds (those with E[B-V] ≳ 0.5). This distinction is useful in the sense that diffuse clouds are relatively warm (T ∼
openaire   +1 more source

Reaction Networks For Interstellar Chemical Modelling: Improvements and Challenges

, 2010
We survey the current situation regarding chemical modelling of the synthesis of molecules in the interstellar medium. The present state of knowledge concerning the rate coefficients and their uncertainties for the major gas-phase processes -- ion ...
Agundez, M., Cuppen, H. M., Geppert, W., Herbst, E., Linnartz, H., Loison, J. C., Oberg, K., Pernot, P., Roueff, E., Smith, I. W. M., Talbi, D., Troe, J., Wakelam, V.   +12 more
core   +3 more sources

How to Imagine Educational AI: The Filling of a Pail or the Lighting of a Fire?

Educational Theory, EarlyView.
Abstract Recent advances in artificial intelligence (e.g., machine learning, generative AI) have led to increased interest in its application in educational settings. AI companies hope to revolutionize teaching and learning by tailoring material to the individual needs of students, automating parts of teachers' jobs, or analyzing educational data to ...
Michał Wieczorek, Alberto Romele
wiley   +1 more source