Galaxies Local Group

Mpc binary galaxies, Local Group, other small groups Virial theorem, X-rays, velocity dispersions of outer satellites, pair-wise velocity differences, approach of M31 (27, 28, 29) 20 - 100 0.02-0.1... 

The Metallicity-Luminosity Relation for Local Group Dwarf Galaxies... 

The accretion history of a parent galaxy is constructed using a semi-analytical code. The full phase-space evolution during each accretion event is then followed separately with numerical simulations [2]. Star-formation and chemical evolution models are implemented within each satellite. The star formation prescription matches the number and luminosity of present-day galaxies in the Local Group, whereas the chemical evolution model takes into account the metal enrichment of successive stellar populations as well as feedback processes. Below we present results of a sample of four such simulated galaxy halos, denoted as Halos HI, H2, H3 and H4. 

NGC 6822 is an isolated irregular galaxy of the Local Group located at 495 kpc from our Galaxy and at 880 kpc from M31, there are no small galaxies in its neighbourhood, and it does not show tidal effects. 

Nowadays, the star formation history (SFH), initial mass function (IMF) and detailed chemical properties have been determined for many dwarfs, both in the Local Group and outside it (e.g. Grebel, Shetrone, Tolstoy, these proceedings). This in principle allows us to base theories of late-type galaxy formation and evolution on firmer grounds, by reducing the free parameter space. 

The Milky Way belongs to a cluster of galaxies called the Local Group that occupies about 3 Gly in space and contains over 30 galaxies, although the precise number is hard to determine. Placing the Milky Way at the centre (Figure 2.14),... 

The three broad classifications (elliptical, spiral and irregular) of star clusters that also cluster together to form the Local Group that contains the Milky Way and the Andromeda Galaxy, along with the Small and Large Magellanic Clouds... 

Local group The collection of galaxies, including the Milky Way and Andromeda, that form part of the Virgo cluster as part of the local supercluster of galaxies. 

We believe that luminous G -rich stars in the Local Group galaxies are not... 

When we left Earth, astronomers had discovered several thousand of these oscillating wonders in our local group of 30 galaxies that includes the Milky... 

What did the numbers look like when I first reviewed the subject in 1987 (9) Pretty much like Schwarzschild s, after allowance for the continued decline in H, and with a few additional data points for the Local Group, for galaxies and clusters with X-ray sizes and temperatures (hence independent Virial-type masses), and for large galaxies (including our own) from the dispersion of velocities of globular clusters and satellite galaxies. 

Other local group galaxies have smaller masses and therefore contain only a few PNe. Abundance data exist for PNe in NGC 6822, NGC 205, NGC 185, Sgr B2, Fornax (see references in Richer Me Call 1995 and Richer et al. 1998). 

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