ASTRO 3 HW 10

If galaxy A is 10 times farther away than galaxy B, then galaxy A is receding -- galaxy B

10 times faster

The cosmic microwave background emission was produced from gas that was at a temperature of -- when the universe was -- of age

3000K; 380,000 years

The geometry of the universe is now known to be -- curvature

flat (Euclidean)

What percentage of the universe consists of ordinary baryonic matter in visible sources such as galaxies, stars, and gas?

5%

Which of the following is NOT observational evidence in favor of the Big Bang?

The tendency of galaxies to cluster

Which of the following standard candle methods revealed the acceleration of the universe?

luminosities of white dwarf supernovae, SN type la

If the universe is isotropic, that means

the distribution of galaxies is the same in all directions

In its earliest phase, the universe was dominated by

radiation

At the current time, the evolution of the universe is dominated by

dark energy

Approximately what percentage of the mass of a rich galaxy cluster is dark matter?

more than 90%

Approximately what percentage of a spiral galaxy’s mass is dark matter?

25-90%

What percentage of the universe consists of dark energy?

68%

A possible energy source for quasars and other active galaxies is

accretion onto supermassive black holes

In the period of inflation, the universe

expanded explosively to increase by more than 10^50 times in diameter in a short time

What is the age of the universe?

13\.8 billion years

The cosmic microwave background radiation is observed to come from

everywhere, all directions

the nuclei of which element was produced during the first two minutes of the universe?

hydrogen

Galaxies that contain large amounts of dark matter

spin faster than expected for their apparent size

At what redshift did the acceleration of the universe being? at z =

0\.4

At what redshift did the first galaxies form? at z =

10