Results 1 to 10 of about 410,793 (220)
Spirals in galaxies have long been thought to be caused by gravitational instability in the stellar component of the disk, but discerning the precise mechanism had proved elusive.
J. Sellwood, K. Masters
semanticscholar +3 more sources
Dark matter cores and cusps in spiral galaxies and their explanations [PDF]
We compare proposed solutions to the core vs cusp issue of spiral galaxies, which has also been framed as a diversity problem, and demonstrate that the cuspiness of dark matter halos is correlated with the stellar surface brightness.
M. Kaplinghat, T. Ren, Hai-Bo Yu
semanticscholar +1 more source
Lopsided spiral galaxies [PDF]
The light distribution in the disks of many galaxies is non-axisymmetric or `lopsided' with a spatial extent much larger along one half of a galaxy than the other, as in M101. Recent near-IR observations show that lopsidedness is common. The stellar disks in nearly 30 % of galaxies have significant lopsidedness, greater than 10 % measured as the ...
Jog, Chanda J, Combes, Francoise
openaire +6 more sources
SUPERLUMINOUS SPIRAL GALAXIES [PDF]
ABSTRACT We report the discovery of spiral galaxies that are as optically luminous as elliptical brightest cluster galaxies, with r-band monochromatic luminosity L r = 8–14L* (4.3–7.5 × 1044 erg s−1).
Lauranne Lanz+4 more
openaire +6 more sources
The Statistical Properties of Spiral Arms in Nearby Disk Galaxies
We analyze 4378 nearby bright disk (S0 and spiral) galaxies selected from the Sloan Digital Sky Survey to characterize their spiral structure and systematically investigate the relationships between spiral arm properties (strength, pitch angle, and ...
Sijie Yu, L. Ho
semanticscholar +1 more source
Galaxy Zoo: dust in spiral galaxies★ [PDF]
We investigate the effect of dust on spiral galaxies by measuring the inclination-dependence of optical colours for 24,276 well-resolved SDSS galaxies visually classified in Galaxy Zoo. We find clear trends of reddening with inclination which imply a total extinction from face-on to edge-on of 0.7, 0.6, 0.5 and 0.4 magnitudes for the ugri passbands. We
Robert C. Nichol+15 more
openaire +7 more sources
We study the role of asymptotic curves in supporting the spiral structure of a N-body model simulating a barred spiral galaxy. Chaotic orbits with initial conditions on the unstable asymptotic curves of the main unstable periodic orbits follow the shape of the periodic orbits for an initial interval of time and then they are diffused outwards ...
M. Harsoula, George Contopoulos
openaire +4 more sources
Let us consider an alternative perspective on climate change: The sum of solar radiation and heat generated by human activity result in a net energy input of 1.96 times that of the Sun on the Earth's surface. The expanding global population is expected to exacerbate this issue. Potential solutions are proposed, including replacement and heat recycling.
Martin Bertau, Gerald Steiner
wiley +1 more source
The spiral structure of galaxies [PDF]
Bernard J. T. Jones, Scott Tremaine
openalex +3 more sources