THE MORPHOLOGICAL DEMOGRAPHICS OF GALAXIES IN THE
... The archeological nature of galaxy evolution studies prevents us from following individual galaxies over time. In consequence we are only left with snapshots at different lookback times from where we attempt, as excavators, to piece together their evolutionary histories from the motion of different ...
... The archeological nature of galaxy evolution studies prevents us from following individual galaxies over time. In consequence we are only left with snapshots at different lookback times from where we attempt, as excavators, to piece together their evolutionary histories from the motion of different ...
Galaxies
... model of galaxy evolution and cosmology based on the paradigm that galaxies form hierarchically around peaks in the dark matter density distribution. Within this framework, astronomers have made great progress in understanding the large-scale clustering of galaxies, as biased tracers of the underlyi ...
... model of galaxy evolution and cosmology based on the paradigm that galaxies form hierarchically around peaks in the dark matter density distribution. Within this framework, astronomers have made great progress in understanding the large-scale clustering of galaxies, as biased tracers of the underlyi ...
Stellar Populations of Dwarf Elliptical Galaxies: UBVRI Photometry
... of low luminosity galaxies. At the same time, Virgo is dynamically young (e.g., Tully & Shaya 1984) and contains several substructural units (Binggeli et al. 1987); thus, with a well selected sample it may be possible to study the evolution of dwarf elliptical galaxies within the cluster itself. Rec ...
... of low luminosity galaxies. At the same time, Virgo is dynamically young (e.g., Tully & Shaya 1984) and contains several substructural units (Binggeli et al. 1987); thus, with a well selected sample it may be possible to study the evolution of dwarf elliptical galaxies within the cluster itself. Rec ...
High-z Universe – cont`d
... DRM104 - Distance estimates from SB Fluctuations DRM224 - Post-AGB stars in the Virgo Cluster Microlensing DRM204 – Detection of Earth-like planets through microlensing DRM231 - Pixel microlensing in M87 ...
... DRM104 - Distance estimates from SB Fluctuations DRM224 - Post-AGB stars in the Virgo Cluster Microlensing DRM204 – Detection of Earth-like planets through microlensing DRM231 - Pixel microlensing in M87 ...
The Milky Way as a galaxy
... thus larger distances, became possible with the astrometric satellite Hipparcos. It operated between November 1989 and March 1993 and measured the positions and trigonometric parallaxes of about 120 000 bright stars, with a precision of 0:00 001 for the brighter targets. With Hipparcos the method ...
... thus larger distances, became possible with the astrometric satellite Hipparcos. It operated between November 1989 and March 1993 and measured the positions and trigonometric parallaxes of about 120 000 bright stars, with a precision of 0:00 001 for the brighter targets. With Hipparcos the method ...
studies - European Southern Observatory
... velocities as a function of galactic radius, for several hundred star-forming galaxies (Methods). Rotation curves give valuable constraints on the baryonic and dark matter mass distributions in massive star-forming disks at the peak of cosmic galaxy formation 10 billion years ago, largely independen ...
... velocities as a function of galactic radius, for several hundred star-forming galaxies (Methods). Rotation curves give valuable constraints on the baryonic and dark matter mass distributions in massive star-forming disks at the peak of cosmic galaxy formation 10 billion years ago, largely independen ...
AST 346, Galaxies, Part 6
... from matter falling in at late times. Near the center, the angular velocity is nearly constant, so there is little differential rotation to inhibit star formation. In many galaxies, central starbursts are visible, but cannot be maintained longer than 0.1 Gyr. At Milky Way’s center, about 107 M is p ...
... from matter falling in at late times. Near the center, the angular velocity is nearly constant, so there is little differential rotation to inhibit star formation. In many galaxies, central starbursts are visible, but cannot be maintained longer than 0.1 Gyr. At Milky Way’s center, about 107 M is p ...
Confirmation of Hostless Type Ia Supernovae Using Hubble Space
... and/or that the timescales for mass transfer or merger are long. The conclusion that at least some SN Ia require progenitors that are > 2 Gyr old relies on the SN Ia rate in rich cluster galaxies, where the majority of the stellar population is old (e.g. Sand et al. 2012). However, there is evidence ...
... and/or that the timescales for mass transfer or merger are long. The conclusion that at least some SN Ia require progenitors that are > 2 Gyr old relies on the SN Ia rate in rich cluster galaxies, where the majority of the stellar population is old (e.g. Sand et al. 2012). However, there is evidence ...
Joint formation of QSOs and spheroids: QSOs as clocks of star
... Key words: dust, extinction – galaxies: formation – quasars: general – cosmology: theory – dark matter – infrared: galaxies. ...
... Key words: dust, extinction – galaxies: formation – quasars: general – cosmology: theory – dark matter – infrared: galaxies. ...
Simulations of the galaxy population constrained by observations
... We propose a specific model in which reincorporation timescales vary inversely with halo mass and are independent of redshift. This produces an evolving galaxy population which fits observed abundances as a function of stellar mass, B- and K-band luminosity at all redshifts simultaneously. It also p ...
... We propose a specific model in which reincorporation timescales vary inversely with halo mass and are independent of redshift. This produces an evolving galaxy population which fits observed abundances as a function of stellar mass, B- and K-band luminosity at all redshifts simultaneously. It also p ...
The formation of disc galaxies in high-resolution moving
... progressively higher mass particles whose mass grows with distance from the target galaxy. This saves computational time while still ensuring the correct cosmological tidal field and mass infall rate for the forming target galaxy. The target galaxies themselves have been selected randomly from a sma ...
... progressively higher mass particles whose mass grows with distance from the target galaxy. This saves computational time while still ensuring the correct cosmological tidal field and mass infall rate for the forming target galaxy. The target galaxies themselves have been selected randomly from a sma ...
Messier 87
Messier 87 (also known as Virgo A or NGC 4486, and generally abbreviated to M87) is a supergiant elliptical galaxy in the constellation Virgo. One of the most massive galaxies in the local universe, it is notable for its large population of globular clusters—M87 contains about 12,000 compared to the 150-200 orbiting the Milky Way—and its jet of energetic plasma that originates at the core and extends outward at least 1,500 parsecs (4,900 light-years), travelling at relativistic speed. It is one of the brightest radio sources in the sky, and is a popular target for both amateur astronomy observations and professional astronomy study.French astronomer Charles Messier discovered M87 in 1781, cataloguing it as a nebulous feature while searching for objects that would confuse comet hunters. The second brightest galaxy within the northern Virgo Cluster, M87 is located about 16.4 million parsecs (53.5 million light-years) from Earth. Unlike a disk-shaped spiral galaxy, M87 has no distinctive dust lanes. Instead, it has an almost featureless, ellipsoidal shape typical of most giant elliptical galaxies, diminishing in luminosity with distance from the centre. Forming around one sixth of M87's mass, the stars in this galaxy have a nearly spherically symmetric distribution, their density decreasing with increasing distance from the core. At the core is a supermassive black hole, which forms the primary component of an active galactic nucleus. This object is a strong source of multiwavelength radiation, particularly radio waves. M87's galactic envelope extends out to a radius of about 150 kiloparsecs (490,000 light-years), where it has been truncated—possibly by an encounter with another galaxy. Between the stars is a diffuse interstellar medium of gas that has been chemically enriched by elements emitted from evolved stars.