Astronomy Cosmology and Deep Space 5

Question 1

The period of rapid exponential expansion just after the Big Bang is called:

Accepted Answer

Inflation

Answer

Cosmic inflation was a fraction-of-a-second burst of enormous expansion in the very early universe.

Question 2

What eventually happens to the light of extremely distant galaxies as space expands?

Accepted Answer

Its wavelength is stretched, increasing redshift

Answer

Expanding space stretches the wavelength of traveling light, producing cosmological redshift.

Question 3

A supernova of Type Ia is valuable to cosmologists because it:

Accepted Answer

Has a consistent peak brightness usable as a distance marker

Answer

Type Ia supernovae explode at a predictable brightness, making them reliable standard candles.

Question 4

What does the term 'redshift' generally tell astronomers about a distant object?

Accepted Answer

How fast it is receding and roughly how far away it is

Answer

Greater redshift indicates faster recession and, via Hubble's Law, greater distance.

Question 5

The eventual fate of the universe in which expansion continues forever and stars burn out is called:

Accepted Answer

The Big Freeze (Heat Death)

Answer

In the Big Freeze, endless expansion leads to a cold, dark, low-energy universe.

Astronomy Practice Test