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11 Cards in this Set

  • Front
  • Back
Galaxies are distributed
as if they are confined to the surface of giant bubbles
Where are the largest voids?
In the centers of these bubbles
The highest concentrations of galaxies occur
along filaments at the intersections of different bubbles.
The mass of the Milky way is determined by...
rotational curves
yet the mass of other galaxies are determined in clusters by...
When the cluster is gravitationally bound the binding energy needed to hold the cluster together is determined and then the mass can be obtained.
What is the problem with this method?
Masses we get are way bigger than in reality BECAUSE of dark matter.

IN FACT in binary systems dark matter may account for up to 90-99% of the mass.
How do galaxies form?
Galaxies form as small fragments (larger than globular clusters) that merge together.

Smaller galaxies get assimilated into larger ones.
when we look into the past (very far away) what do we see?
blue galaxies the building blocks of modern day galaxies.
Where do galaxies with supermassive black holes in their centers fit into the evolution of galaxies?
it is believed that those with black holes in their centers were very distant quasars.

So it is believed that quasars are in a stage of early galaxy development.
Recent measurements have found a relationship between the mass of the central black hole and the size of the galactic bulge. What is the pattern?
The larger the black hole the larger the bulge.
Overall galaxy evolution
As small galaxies clump together to form larger ones= a black hole forms in the middle.

With plenty of fuel at the beginning burning is bright= quasar

additional mergers and depletion of fuels results in radio and seyfert galaxies (active galaxies).

Upon futher depletion of fuels NORMAL GALAXIES with a dormant black hole are formed.