Exam 16: Beyond Our Solar System

A star is observed through a telescope, and a measurement of the star's spectrum is made. The left side of the star appears to be bluer than the center of the star, but the right side appears to be redder. What's going on here? Interpret these observations as fully as possible.

If the universe is sufficiently dense, gravity will someday pull it all back together in an event called ________, sort of like the big bang in reverse.

Nebulae are strands or clumps of ________.

Examine this photo of the Milky Way taken from Earth shortly after sunset. If you were there when this photo was taken, and a friend asked you to explain what you're seeing here, what features would you point out to them? What explanations would you give?

Nasa image This image is a "map" of the universe's microwave background radiation. It shows 13.77 billion year old temperature fluctuations from shortly after the big bang (shown as color differences)that correspond to the gravitational "seeds" that grew to become the galaxies. Why is this heterogeneity important?

A star having the same mass of Earth's Sun is likely to first evolve into a ________ before becoming a ________.

Observations of the redshift of most galaxies led to the idea of an expanding universe, also known as ________ theory.

________ are objects from which light cannot escape because of the immense gravitational pull at its surface. They are produced during supernova events.

Examine the figure. Which of the four lettered locations on this graph is closest to the position that Earth's Sun will end up in at the end of its stellar life cycle?

When galaxies collide, each of the individual stars in one galaxy will smash into an equivalent star in the second galaxy.

A star's ________ can be determined from its color.

Examine the figure and then evaluate the following statement: Based on its shape, this is a barred spiral galaxy.

Some of the largest and the smallest galaxies are elliptical in shape.

When a star is so dense that its atoms have their electrons smashed in toward the nucleus (resulting in densities about a million times greater than water), the resulting material is called ________.

Examine the figure. At the center of this object, a cosmologist would expect to find ________.

The Hertzsprung-Russell diagram shows ________.

At the center of the Milky Way galaxy, a supermassive black hole is thought to exist. Similar supermassive black holes are thought to exist at the center of spiral galaxies throughout the universe. The stars that originally formed these black holes must have been extraordinarily large. Why would stars potentially have been much larger earlier in the history of the universe?

Two galaxies are located at some distance from Earth. The first, Galaxy A, is located 50 million light-years from Earth. The second, Galaxy B, is located 150 million light-years from Earth. How should the red-shift of Galaxy A compare to Galaxy B? Explain.

A light-year is ________.