AY 101-051                                                       Summer2011 
                                    QUIZ #8
1.	The cosmic microwave background radiation originated when
A)	the first stars formed.
B)	atomic nuclei were first stable.
C)	THE UNIVERSE FIRST BECAME TRANSPARENT.
D)	Matter and antimatter were last in balance.

2.	The resolution of Olbers’ paradox is that the dark night sky tells us that 
A)	THE uNIVERSE CANNOT BE INFINITE IN BOTH SPACE AND TIME.
b)	the Universe must contain large amounts of absorbing material.
c)	the Universe has always been here.
d)	we are located near one edge of the Universe.

3.	Processes in the early Universe were responsible for the relative amounts of 
A)	HYDROGEN, DEUTERIUM, AND HELIUM.	c) radioactive elements.
b)	carbon, nitrogen, and oxygen.		d) ionized and neutral gas.

4.	Looking at very distant galaxy clusters, we find that
a)	their galaxy content has remained unchanged over time.
B)	THEIR SPIRAL GALAXIES HAVE GRADUALLY TRANSFORMED INTO OTHER TYPES.
c)	they have included more spirals as time goes on.
d)	the galaxies are splitting into smaller ones as time goes on.

5.	The Cosmological Principle says that			
A)	THE OVERALL PROPERTIES OF THE uNIVERSE LOOK THE SAME AS SEEN FROM ANYWHERE.
b)	the overall properties of the Universe always look the same.
c)	our location must be nearly central in the Universe.
d)	explanations should be as simple as possible while fitting the facts.

6.	In the Universe today, rich clusters of galaxies mostly contain
A)	ELLIPTICAL GALAXIES.		c) irregular galaxies.
b)	spiral galaxies.			d) radio galaxies.

7.	We know about the very hot gas deep in intergalactic space because
A)	IT BLOCKS SPECIFIC WAVELENGTHS OF LIGHT FROM QUASARS IN THE BACKGROUND.
b)	it produces a bright glow in the ultraviolet.
c)	of the cosmic microwave background.
d)	it heats the gas at the edges of galaxies.

8.	The age of the Universe derived from its expansion is most nearly 
a)	10 million years.			C) 15 BILLION YEARS.
b)	one billion years.		d) one trillion years.

9.	Some properties of the Universe are explained if the early Universe underwent
A)	A BRIEF PERIOD OF EXPONENTIALLY ACCELERATED EXPANSION.
b)	a series of cycles of expansion and contraction.
c)	a long period of static form followed by rapid expansion,
d)	the massive production of black holes.

10.	Recent observations of supernovae show that the expansion of the Universe is
a)	going on at a constant rate.
b)	slowing down as a result of the gravity of everything in it.
C)	ACCELERATING FOR SOME UNKNOWN REASON.
d)	cycling over time between positive and negative rates.