Question 1

The Sun's location in the Milky Way Galaxy is

Accepted Answer

A) very near the galactic center. 
B) in the halo of the galaxy,about 28,000 light-years above the galactic disk. 
C) at the very outer edge of the galactic disk. 
D) in the galactic disk,roughly halfway between the center and the outer edge of the disk.

Question 2

Briefly describe the star-gas-star cycle.

Accepted Answer

The answer of Briefly describe the star-gas-star cycle....

Question 3

Process of Science: The theory of spiral arms explain why short-lived,massive stars are found there but longer-lived,low mass stars should last for many orbits around a galaxy and therefore be much more spread out.How might you test that prediction?

Accepted Answer

The answer of Process of Science: The theory of spiral...

Question 4

Red and orange stars are found evenly spread throughout the galactic disk,but blue stars are typically found

Accepted Answer

A) in the halo. 
B) only in or near star-forming clouds. 
C) only in the central bulge. 
D) evenly spread throughout the galactic disk.

Question 5

How does the diameter of the disk of Milky Way Galaxy compare to its thickness?

Accepted Answer

A) The diameter and thickness are roughly equal. 
B) The diameter is about 100 times as great as the thickness. 
C) The diameter is about 10 times as great as the thickness. 
D) The diameter is about 100,000 times as great as the thickness.

Question 6

What are the Magellanic Clouds?

Accepted Answer

A) two small galaxies that probably orbit the Milky Way Galaxy 
B) two nebulae located in the disk of the Milky Way Galaxy and visible only from the Southern Hemisphere 
C) star-forming clouds found in the constellation Orion 
D) the clouds of dust and gas found interspersed in many places throughout the Milky Way Galaxy

Question 7

Astronomers observe huge bubbles of hot gas,some over a thousand light-years across,in the Milky Way.What is their cause?

Accepted Answer

The answer of Astronomers observe huge bubbles of hot gas,some...

Question 8

The most common form of gas in the disk of the Milky Way Galaxy is

Accepted Answer

A) molecular hydrogen. 
B) gas in hot bubbles. 
C) atomic hydrogen gas. 
D) gas in stellar winds.

Question 9

Open clusters and young stars are generally found only in the disk of the galaxy and not in the halo.

Accepted Answer

A) True 
 B)False

Question 10

Where does most star formation occur in the Milky Way Galaxy?

Accepted Answer

A) everywhere throughout the galactic disk 
B) in the central bulge 
C) within the halo 
D) in the spiral arms

Question 11

What do astronomers consider heavy elements?

Accepted Answer

A) elements that are heavier than iron 
B) elements that are heavier than carbon 
C) elements that are heavier than hydrogen 
D) elements that are heavier than uranium 
E) all elements besides hydrogen and helium

Question 12

Spiral arms appear bright because

Accepted Answer

A) they contain more hot young stars than other parts of the disk. 
B) they contain far more stars than other parts of the galactic disk. 
C) they contain more molecular clouds than other parts of the disk. 
D) they are the only places where we find stars within the disk of the galaxy.

Question 13

All heavy elements are made during supernova events.

Accepted Answer

A) True 
 B)False

Question 14

How do we know that halo stars are older,on average,than disk stars?

Accepted Answer

A) Halo stars orbit in random directions but disk stars have more ordered orbits. 
B) There are no blue halo stars. 
C) There are no red disk stars. 
D) Theories of galaxy formation tell us that the halo formed earlier than the disk. 
E) We see evidence for new stars forming in the disk today.

Question 15

Harlow Shapley concluded that the Sun was not in the center of the Milky Way Galaxy by

Accepted Answer

A) looking at the shape of the "milky band" across the sky. 
B) mapping the distribution of stars in the galaxy. 
C) mapping the distribution of globular clusters in the galaxy. 
D) mapping the distribution of gas clouds in the spiral arms. 
E) looking at other nearby spiral galaxies.

Question 16

Which of the following statements about globular clusters is false?

Accepted Answer

A) Globular clusters contain many thousands of stars. 
B) Globular cluster stars are more than 12 billion years old. 
C) Globular cluster ages increase with distance from the Milky Way. 
D) Globular clusters are distributed spherically around the Milky Way. 
E) Globular cluster stars are very metal-poor relative to the Sun.

Question 17

Compared with stars in the disk,orbits of stars in the halo

Accepted Answer

A) are relatively uniform to each other. 
B) are elliptical,with random orientation. 
C) are elliptical but orbiting in the same direction. 
D) do not have to be around the galactic center. 
E) do not have to pass through the plane of the galaxy.

Question 18

The primary way that we observe the atomic hydrogen that makes up most of the interstellar gas in the Milky Way is with

Accepted Answer

A) ground-based visible-light telescopes. 
B) space-based ultraviolet telescopes. 
C) X-ray telescopes. 
D) radio telescopes observing at a wavelength of 21 centimeters.

Question 19

What is a shock front?

Accepted Answer

A) a wave of pressure that moves faster than the speed of sound 
B) a wave of pressure that moves slightly slower than the speed of sound 
C) a wave of pressure that moves faster than the speed of light 
D) a wave of electromagnetic energy that can create electrical shocks 
E) the wave created when protons slam into electrons

Question 20

How can we see through the interstellar medium?

Accepted Answer

A) by observing in high-energy wavelengths such as X-rays and long wavelengths of light such as radio waves 
B) by observing only the brightest visible sources 
C) by using only the biggest telescopes 
D) by using telescopes above the Earth's atmosphere 
E) We cannot see through the interstellar medium.

Exam 19: Our Galaxy