Related papers: Creation of Spiral Galaxies
It has been thought for many years that the Milky Way is an overly large spiral galaxy. Using Cephied distances to 17 spiral galaxies we calculate the true linear diameters of those galaxies. These diameters are then compared to that of the…
The most important theory of the spiral arms of galaxies is the density wave theory based on the Lin-Shu dispersion relation. However, the density waves move with the group velocity towards the inner Lindblad resonance and tend to…
Globular clusters are compact, gravitationally bound systems of up to a million stars. The GCs in the Milky Way contain some of the oldest stars known, and provide important clues to the early formation and continuing evolution of our…
Using recent observational data, we construct a set of multi-component equilibrium models of the disk of a Milky Way-like galaxy. The disk dynamics are studied using collisionless-gaseous numerical simulations, based on the joined…
Gaia recently revealed a two-armed spiral pattern in the vertical phase-space distribution of the inner Galactic disk (guiding radius $R_\textrm{g} \sim 6.2$ kpc), indicating that some non-adiabatic perturbation symmetric about the…
We assume that the individual stars which are located at the peripheral parts of the spiral galaxies are experiencing a drag force acting upon them radially. Such a force might be produced by some sort of a dynamically generated viscous…
The phase spiral is a perturbation to the vertical phase-space distribution of stars in the Milky Way disk. We study the phase spiral's properties and how they vary with spatial position, in order to constrain its origin and evolution, as…
If our universe was born as a baby universe on the other side of the event horizon of a black hole existing in a parent universe, then the corresponding white hole at rest provides the absolute frame of reference in the universe. In this…
The physical phenomena contributing to the galaxy growth can be tested all the way to z= 1. Galaxy mass, extinction, star formation and gas metal abundance can be measured in a robust way, as well as the distribution of the galaxy…
Nearly a century after the true nature of galaxies as distant "island universes" was established, their origin and evolution remain great unsolved problems of modern astrophysics. One of the most promising ways to investigate galaxy…
Collisions and mergers of gas-rich galaxies trigger bursts of star and cluster formation. Of the thousands of clusters typically formed during a major merger, only the most massive and compact survive for Gigayears as globular clusters…
The most massive black holes, lurking at the centers of large galaxies, must have formed less than a billion years after the big bang, as they are visible today in the form of bright quasars at redshift larger than six. Their early…
We use hydrodynamic cosmological zoom-in simulations from the FIRE project to explore the morphologies and kinematics of fifteen Milky Way (MW)-mass galaxies. Our sample ranges from compact, bulge-dominated systems with 90% of their stellar…
The origin of grand design spiral structure in galaxies is still under debate but one of promising scenarios involves tidal interactions. We use N-body simulations to study the evolution of a Milky Way-size galaxy in a Virgo-like cluster.…
High resolution gravity plus smoothed particle hydrodynamics simulations are used to study the formation of galaxies within the context of hierarchical structure formation. The simulations have sufficient dynamic range to resolve from ten…
We consider models of gas flow in spiral galaxies in which the spiral structure has been excited by various possible mechanisms: a global steady density wave, self-gravity of the stellar disc and an external tidal interaction, as well as…
Spiral patterns in some disc galaxies have two arms in the centre, and three or more arms on the periphery. The same result is also obtained in numerical simulations of stellar and gaseous discs. We argue that such patterns may occur due to…
The density-wave theory of galactic spiral-arm structure makes a striking prediction that the pitch angle of spiral arms should vary with the wavelength of the galaxy's image. The reason is that stars are born in the density wave but move…
Equations of motion, in cylindrical co-ordinates, for the observed rotation of gases within the gravitational potential of spiral galaxies have been derived from Carmeli's Cosmological General Relativity theory. A Tully-Fisher type relation…
Massive galaxies, such as nearby ellipticals, have relatively low number densities, yet they host the majority of the stellar mass in the universe. Understanding their origin is a central problem of galaxy formation. Age dating of stellar…