Exam 17: Hubbles Law and Dark Matter: the Large-Scale Structure of the Cosmos

When we see a doubling of the image of single quasar, the body creating the gravity lens is just a brown dwarf close to us.

Computer simulations of the early universe clearly show the process of of smaller galaxies into larger ones.

Our theories of galaxy formation are just as well developed and tested as are our theories of star and planet formation.

What direct evidence has been obtained for the existence of dark matter in galaxy clusters?

The greatest redshifts yet observed for quasars is about

Quasars may come from mergers of black holes in early galaxies.

The greater the mass of the foreground cluster of galaxies, the more warped the images of the distant galaxies are when they undergo gravitational lensing.

What are redshift surveys designed to show?

In size and mass, irregular galaxies tend to be than spirals.

Relate black holes in the early galaxies to quasars.

Rotation curves for spiral galaxies show

Astronomers have discovered two black holes in the process of merging.

Astronomers believe that a spiral galaxy may form

The process where some fraction of the quasar's enormous energy output is absorbed by the surrounding galactic gas is called _ .

Galaxies contain less mass as dark matter than as visible stars.

Hubble reveals the most distant (first) galaxies were bluer than those of today.

Quasar lines are an indication of intervening cooler gas.

How can some mergers activate spirals, and others destroy them?

The rapid decline in quasars 10 billion years ago signifies a rapid decline in galactic mergers.