Results 51 to 60 of about 8,317 (217)

Les galaxies spirales

, 2021
Notre vision des galaxies a beaucoup changé depuis l’ère des grands relevés de galaxies, tels que le Sloan, qui nous apportent une grande statistique avec des millions de galaxies. La classification de la séquence de Hubble est toujours très utilisée, mais elle s’est enrichie de grandes catégories basées sur les couleurs, qui tracent la formation ...
openaire   +1 more source

SECULAR EVOLUTION OF SPIRAL GALAXIES [PDF]

Journal of The Korean Astronomical Society, 2003
15 pages, 8 figures, Invited talk presented at the 2nd APCTP workshop on Astrophysics, Pohang, Korea (June 2002)
openaire   +2 more sources

Rotating shallow water modeling of planetary,astrophysical and plasma vortical structures (plasma transport across a magnetic field,model of the jupiter's GRS, prediction of existence of giant vortices in spiral galaxies)

Discrete Dynamics in Nature and Society, 1999
Three kinds of results have been described in this paper. Firstly, an experimental study of the Rossby vortex meridional drift on the rotating shallow water has been carried out.
M. V. Nezlin, A. Yu Rylov, E. N. Snezhkin, K. B. Titishov, G. P. Chernikov   +4 more
doaj   +1 more source

Spiral structure in external galaxies [PDF]

Symposium - International Astronomical Union, 1970
The need for observing at least four different categories of optical objects for a satisfactory definition of optical spiral structure is emphasized. A sequence of optical form-types for the description of spiral structure is outlined. A pronounced difference in the nature of the spiral structure of the outer and inner parts of Messier 33 is ...
openaire   +1 more source

Modified Newtonian Dynamics: A Falsification of Cold Dark Matter

Advances in Astronomy, 2009
The only viable alternative to dark matter is one in which Newtonian dynamics or gravity breaks down in the limit of low accelerations, as in modified Newtonian dynamics (MONDs).
R. H. Sanders
doaj   +1 more source

Magnetic-Field Vector Maps of Nearby Spiral Galaxies

Galaxies, 2019
We present a method for determining the directions of magnetic-field vectors in a spiral galaxy using two synchrotron polarization maps, an optical image, and a velocity field.
Hiroyuki Nakanishi, Kohei Kurahara, Kenta Anraku   +2 more
doaj   +1 more source

Unusual Gas Structure in an Otherwise Normal Spiral Galaxy Hosting GRB 171205A/SN 2017iuk [PDF]

, 2022
M. Arabsalmani, Sambit Roychowdhury, Florent Renaud, Andreas Burkert, Éric Emsellem, E. Le Floc’h, E. Pian   +6 more
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The spatially resolved star formation history of the dwarf spiral galaxy NGC 5474 [PDF]

, 2023
Giacomo Bortolini, M. Cignoni, Elena Sacchi, M. Tosi, F. Annibali, R. Pascale, M. Bellazzini, D. Calzetti, Angela Adamo, Daniel A. Dale, Michele Fumagalli, J. S. Gallagher, Kathryn Grasha, Kelsey E. Johnson, Sean T. Linden, Matteo Messa, Göran Östlin, Elena Sabbi, Aida Wofford   +18 more
openalex   +1 more source

The Impacts of Bars, Spirals, and Bulge Size on Gas-phase Metallicity Gradients in MaNGA Galaxies

The Astrophysical Journal
As galaxies evolve over time, the orbits of their constituent stars are expected to change in size and shape, moving stars away from their birth radius. Radial gas flows are also expected. Spiral arms and bars in galaxies are predicted to help drive this
M. E. Wisz, Karen L. Masters, Kathryne J. Daniel, David V. Stark, Francesco Belfiore   +4 more
doaj   +1 more source

On the Role of Noncircular Motions in MaNGA Galaxies. I. Global Properties

The Astrophysical Journal
Noncircular (NC) motions represent the imprints of nonaxisymmetric structures in galaxies, providing opportunities to study the physical properties of gas departing from circular rotation.
Carlos López-Cobá, Lihwai Lin, Justus Neumann, Matthew A. Bershady   +3 more
doaj   +1 more source