Re: Is there more chance for life in galaxies which are in a non crowded space

Dear Shira
Most galaxies are part of a group, cluster or supercluster, so having a 
galaxy which is not in a crowded part of the universe is slightly unusual. 

Groups of galaxies are the smallest aggregates of galaxies. They 
typically contain fewer than 50 galaxies in a diameter of about 2 
megaparsec (Mpc) (which is 10^22 m for distance comparisons). Their mass are 
approximately 10^13 solar masses. The spread of velocities for the 
individual galaxies is about 150 km/s.

The group which contains our own galaxy, the Milky Way, is called the 
Local Group, and contains more than 40 galaxies.

Clusters are larger than groups, although there is no sharp dividing line 
between a group and a cluster. When observed visually, clusters appear to 
be collections of galaxies held together by mutual gravitational 
attraction. However their velocities are too large for them to remain 
gravitationally bound by their mutual attractions, implying the presence 
of an additional invisible mass component. X-ray studies have revealed 
the presence of large amounts of intergalactic gas. This gas is very hot, 
around 10^8 K, and hence emits X-rays. The total mass of the gas is greater 
than that of the galaxies by roughly a factor of two. However this is 
still not enough mass to keep the galaxies in the cluster. Since this gas 
is in approximate equilibrium with the overall cluster gravitational 
field, its distribution in the cluster traces out the overall cluster 
gravitational field, and therefore allows calculation of the total mass 
distribution in the cluster. It turns out the total mass deduced from 
this measurement is much larger than the mass of the galaxies or the hot 
gas. The missing component is known as dark matter and its nature is 
unknown. In a typical cluster perhaps only 5% of the total mass is in the 
form of galaxies, maybe 10% in the form of hot X-ray emitting gas and the 
remainder is dark matter.

Clusters typically have the following properties.

They contain 50 to 1000 galaxies, hot X-ray emitting gas and large 
amounts of dark matter 
The distribution of these three components is approximately the same in 
the cluster. 
They have total masses of 10^14 to 10^15 solar masses. 
They typically have a diameter of 8Mpc (or 10^23 m for distance 
comparisons). 
The spread of velocities for the individual galaxies is about 800-1000 
km/s. 
The average distance between clusters is approximately 10 Mpc. 
Notable galaxy clusters in the relatively nearby universe include the 
Virgo cluster and the Coma cluster. A very large aggregation of galaxies 
known as the Great Attractor, dominated by the Norma cluster, is massive 
enough to affect the local expansion of the universe (Hubble flow).

Note: clusters of galaxies should not be confused with star clusters such 
as galactic clusters and open clusters, which are structures within 
galaxies, as well as globular clusters, which typically orbit galaxies.

Groups, clusters and some isolated galaxies form even larger structures, 
the superclusters. At the very largest scales of the visible universe, 
matter is gathered into filaments and walls surrounding vast voids. This 
structure resembles a foam.

The following sites may be helpful: 
http://www.answers.com/

hope this is helpful
James Armour

[Moderator's note: The environment would only affect the chances of life if the interactions
between the galaxies disturbed the stellar systems.  This can happen
when galaxies collide or merge, but most of the galaxy usually remains
intact, so it probably wouldn't have a big effect on existing solar systems. 
However, these interactions also disturb the diffuse gas in the galaxies, causing
a brief burst of star formation and clearing the rest out.  So galaxies in crowded environments
have few young stars, so there's less of a chance of life forming in new systems.]