Stellar Populations
Related Category: Astronomy: General
two broadly contrasting distributions of star types that are characteristic of different parts of a galaxy.
Stellar population
Stars observed in our galaxy appear to group into two general types called Population I and Population II.
stellar populations
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Stellar Populations
type I: metal-rich (2-3%) disk stars which formed from material enriched with metals from a previous star-forming generation. type II: metal-poor (0.001-0.1%) halo stars.
STELLAR POPULATIONS
In the 1940s, elliptical galaxies were assigned by Walter Baade to his Population II, ...
STELLAR POPULATIONS
Aside from their shapes, the three components of the Galaxy"disk, bulge, and halo"have several other properties that distinguish them from one another.
Stellar Population - A group of stars that are similar in spatial distribution, chemical composition, and age
Stony Meteorite - A meteorite made of silicate rock ...
Stellar Population
A Galaxy-wide group of stars of all types that have similar ages, locations, kinematics, and metallicities.
[edit] Stellar population
Galactic Center of Milky way and a meteor ...
Stellar populations in galaxies - resolved systems
Jan 31
Stellar populations in galaxies - integrated light ...
Stellar Populations
Milky Way at Many Wavelengths
The Milky Way - Cambridge
Galaxy Types ...
Stellar Populations :
Pop I : young, disk, enriched by heavy elements
Pop II : old, halo, depleted in heavy elements
Galaxy Formation : ...
For a typical stellar population one supernova is produced for every 100 solar masses of stars formed --- this can give a rough idea of the rate in a galaxy of a given age and mass (in a galaxy like the Milky Way, 1-10 per century or so).
with a strong concentration of stars (and gas and dust) within 3,000 light-years (ly) of the galactic plane, which includes the so-called "thin disk" that has more relatively younger stars within 1,500 ly of the plane (more on stellar population ...
However, by chance, there is a small region of the galactic interior which has relatively few patches of dust between us and the center, letting us study the Galactic Bulge's stellar population in detail.
The situation is further complicated by the fact that different stellar populations generally do not have all types of stars in them.
Apart from being kinematically distinct, the thick and thin disks also differ in their stellar populations. Thin disks contain young stars, while the stars in thick disks are almost all older than 10 billion years.
All the stars in a globular cluster were formed at the same time and from the same cloud of gas; thus, they constitute a single stellar population.
The Hubble images, taken with the Advanced Camera for Surveys, identify three stellar populations in the SMC and in the region of the NGC 346 nebula -- a total of 70,000 stars. The oldest population is 4.5 billion years, roughly the age of our Sun.
The Antlia Dwarf seems to be dominated by an old stellar population, similar to what has been found for most other dwarf spheroidal galaxies in the Local Group.
and Bridges determined that these foreign-born globular star clusters actually make up about one quarter of our Milky Way globular star cluster system, implying that tens of millions of stars have joined and added to our Galaxy's stellar population ...
Globular One (or G1) has several stellar populations and a structure too massive for an ordinary globular. As a result, some consider G1 to be the remnant core of a dwarf galaxy that was consumed by M31 in the distant past.
Also, the structure of the Milky Way Galaxy, our place in it, and how we determine these things. The rotation curve and the existence of the dark matter halo, stellar populations, and the galactic center are also discussed.
For comparison, M67 is 5 x more distant and twice as large as Beehive (M44) in the same constellation. M67 seems to be about 10 billion years old - it is one of the oldest open clusters and its stellar population resembles those of globulars.
Did these cosmic shards and fragments evolve into today's recognizable galaxies? Are they as small as they appear, but bright from great bursts of star formation? Or, are they massive, with much of their stellar population hidden from view by clouds ...
 See also: Population, Galaxy, Galaxies, Cluster, Star
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