Consider three periods in the history of the Universe: one million years after the Big Bang (age = 1 million years), about five billion years ago (age = 9 billion years), and today. What is the ranking in the expansion rate of the Universe in these three period, from fastest to slowest expansion: O 1 million years, today, 9 billion years. O today, 1 million years, 9 billion years. today, 9 billion years, 1 million years. O 1 million years, 9 billion years, today.

Another explanation for the Universe is the Steady State Hypothesis. The Steady State Hypothesis says that the Universe has always existed and is infinite in extent. Which of the following supports the Big Bang Theory and which supports the Steady State Model. (Select B-Big Bang Theory, S-Steady State Model, If the first is B and the rest S, enter BSSSSS). A) An observation that some globular clusters show M-type stars that have evolved off the main sequence.   B) The measurement of redshifts that show galaxies appear to be moving away from each other and the Universe is expanding.   C) A measurement that shows the density of the Universe is close to the critical density.   D) The measurement of the microwave background radiation.   E) Observing that galaxies at very large distances look identical to those in the nearby universe.

TRUE OR FALSE: In an unbounded universe, all hydrogen will be used up in about a trillion years

The Milky Way grew through merging with many smaller galaxies. What are the observational signatures of this process? O The motion of old stars in the bulge and halo of our galaxy are randomly orientated, meaning they were formed from collisions of small, accreted, galaxies all on different paths. O The ordered motion of the bulge / halo stars means that they came from many objects. The random motions of stars in the disk means it was formed from collisions of small, accreted, galaxies. O The motion of young stars in the disk are all in the same direction, meaning they came in as seperate objects.

For the graph shown above, a) what quantity would you label the y-axis with if the distance is between galaxies and the Earth? Explain your answer. Think through what we know is happening, motion-wise, out there in the galaxy. b) Also explain why you think there are dots and a solid line, on the graph.

What are a couple of scientific speculations that describe the future of our universe?

What is our "cosmic address"?