Question 1

How would our estimate of the mass of the galaxy be changed if it were discovered that the period of revolution of the Sun is actually twice as long as it is now thought to be?

Accepted Answer

A) It would be increased 
B) It would be decreased 
C) It would be unchanged 
D) The Sun's period is irrelevant to determining the mass of the galaxy 
A) It would be increased 
B) It would be decreased 
C) It would be unchanged 
D) The Sun's period is irrelevant to determining the mass of the galaxy B

Question 2

Which of the following objects is not found primarily in the spiral arms of a galaxy?

Accepted Answer

A) White dwarf stars 
B) HII regions 
C) Supernovae 
D) O and B stars 
A) White dwarf stars 
B) HII regions 
C) Supernovae 
D) O and B stars A

Question 3

The 3 kpc arm is

Accepted Answer

A) A spiral arm rotating the wrong way about the nucleus 
B) Gas falling inward toward the center of the galaxy 
C) Evidence of explosive activity at the nucleus of the galaxy 
D) The arm containing most of the naked eye stars we see 
A) A spiral arm rotating the wrong way about the nucleus 
B) Gas falling inward toward the center of the galaxy 
C) Evidence of explosive activity at the nucleus of the galaxy 
D) The arm containing most of the naked eye stars we see C

Question 4

The rotation curve of the Milky Way galaxy is non-Keplerian at large distances from the center.This is evidence for

Accepted Answer

A) Rigid body rotation throughout the galaxy 
B) Large amounts of unseen mass in the outer galaxy or halo 
C) Gravitational waves in the galaxy 
D) Spiral arms 
E) Peculiar velocities of distant stars. 
A) Rigid body rotation throughout the galaxy 
B) Large amounts of unseen mass in the outer galaxy or halo 
C) Gravitational waves in the galaxy 
D) Spiral arms 
E) Peculiar velocities of distant stars.

Question 5

Which of the following types of objects are mostly found in the spiral arms of the galaxy?

Accepted Answer

A) O and B stars 
B) Solar type stars 
C) Pulsars 
D) Brown dwarfs 
A) O and B stars 
B) Solar type stars 
C) Pulsars 
D) Brown dwarfs

Question 6

The distance to the center of the galaxy is about

Accepted Answer

A) 8 astronomical units 
B) 8 parsecs 
C) 8 light years 
D) 8 kiloparsecs 
A) 8 astronomical units 
B) 8 parsecs 
C) 8 light years 
D) 8 kiloparsecs

Question 7

About how long does it take for the Sun to complete one trip around the galaxy?

Accepted Answer

A) 25 thousand years 
B) 2.5 million years 
C) 250 million years 
D) 25 billion years 
A) 25 thousand years 
B) 2.5 million years 
C) 250 million years 
D) 25 billion years

Question 8

The halo population of stars is

Accepted Answer

A) Very young with much dust and gas 
B) Quite old,containing few metals 
C) Mixed,with about equal populations of young and old stars 
D) Mostly second and third generation stars 
E) Nearly all stellar remnants at the present epoch 
A) Very young with much dust and gas 
B) Quite old,containing few metals 
C) Mixed,with about equal populations of young and old stars 
D) Mostly second and third generation stars 
E) Nearly all stellar remnants at the present epoch

Question 9

The oldest stars in the galaxy are found

Accepted Answer

A) In globular clusters in the halo 
B) At the center of the galaxy 
C) On the front rim of spiral arms 
D) In the galactic disk 
A) In globular clusters in the halo 
B) At the center of the galaxy 
C) On the front rim of spiral arms 
D) In the galactic disk

Question 10

Where are globular clusters located in the galaxy?

Accepted Answer

A) In the nucleus 
B) In the disk 
C) In the spiral arms 
D) In the halo 
A) In the nucleus 
B) In the disk 
C) In the spiral arms 
D) In the halo

Question 11

What kind of star is located at the center of an HII region?

Accepted Answer

A) A hot one 
B) A cool one 
C) A young one 
D) A main sequence star 
A) A hot one 
B) A cool one 
C) A young one 
D) A main sequence star

Question 12

The mass of the galaxy has been found by

Accepted Answer

A) Counting the stars it contains 
B) Determining its gravitational force on nearby galaxies 
C) Estimating the number of interstellar clouds it contains 
D) Applying Kepler's third law to the Sun's orbit 
A) Counting the stars it contains 
B) Determining its gravitational force on nearby galaxies 
C) Estimating the number of interstellar clouds it contains 
D) Applying Kepler's third law to the Sun's orbit

Question 13

What effect do interstellar dust particles have on the appearance of a distant star?

Accepted Answer

A) They make it look bluer and brighter 
B) They make it look bluer and dimmer 
C) They make it look redder and brighter 
D) They make it look redder and dimmer 
A) They make it look bluer and brighter 
B) They make it look bluer and dimmer 
C) They make it look redder and brighter 
D) They make it look redder and dimmer

Question 14

What kind of object creates an evacuated,very hot bubble in the interstellar gas?

Accepted Answer

A) A red giant star 
B) A black hole 
C) A supernova 
D) A globular cluster 
A) A red giant star 
B) A black hole 
C) A supernova 
D) A globular cluster

Question 15

The velocity of the sun in its orbit around the galactic center is considered to be around what value?

Accepted Answer

A) 150 km/sec 
B) 220 km/sec 
C) 340 km/sec 
D) 541 km/sec 
A) 150 km/sec 
B) 220 km/sec 
C) 340 km/sec 
D) 541 km/sec

Question 16

What evidence do we have that there is hidden mass in the galaxy?

Accepted Answer

A) Cool clouds of hydrogen 
B) RR Lyrae variable stars in globular clusters 
C) Non-Keplerian (flat)rotation curve at large radii 
D) Missing neutrinos from the Sun 
E) Dusty regions in the plane 
A) Cool clouds of hydrogen 
B) RR Lyrae variable stars in globular clusters 
C) Non-Keplerian (flat)rotation curve at large radii 
D) Missing neutrinos from the Sun 
E) Dusty regions in the plane

Question 17

What keeps the matter in an HII region ionized?

Accepted Answer

A) Ultraviolet radiation from a star or stars 
B) Chemical reactions 
C) Collisions between gas clouds 
D) Beams of electrons 
A) Ultraviolet radiation from a star or stars 
B) Chemical reactions 
C) Collisions between gas clouds 
D) Beams of electrons

Question 18

In order to make a scale model of the galaxy in which stars are represented by salt grains,how far apart would neighboring salt grains be?

Accepted Answer

A) 1000 miles 
B) 10 miles 
C) 100 yards 
D) 1 yard 
A) 1000 miles 
B) 10 miles 
C) 100 yards 
D) 1 yard

Question 19

The stars in globular clusters are

Accepted Answer

A) Young and metal rich 
B) Young but metal poor 
C) Old and metal poor 
D) Old and metal rich 
A) Young and metal rich 
B) Young but metal poor 
C) Old and metal poor 
D) Old and metal rich

Question 20

The 21 cm line is emitted by

Accepted Answer

A) Hydrogen atoms 
B) Interstellar dust 
C) A gas of hot protons and electrons 
D) CO molecules 
A) Hydrogen atoms 
B) Interstellar dust 
C) A gas of hot protons and electrons 
D) CO molecules

Exam 22: The Milky Way

How would our estimate of the mass of the galaxy be changed if it were discovered that the period of revolution of the Sun is actually twice as long as it is now thought to be?

Which of the following objects is not found primarily in the spiral arms of a galaxy?

The 3 kpc arm is

The rotation curve of the Milky Way galaxy is non-Keplerian at large distances from the center.This is evidence for

Which of the following types of objects are mostly found in the spiral arms of the galaxy?

The distance to the center of the galaxy is about

About how long does it take for the Sun to complete one trip around the galaxy?

The halo population of stars is

The oldest stars in the galaxy are found

Where are globular clusters located in the galaxy?

What kind of star is located at the center of an HII region?

The mass of the galaxy has been found by

What effect do interstellar dust particles have on the appearance of a distant star?

What kind of object creates an evacuated,very hot bubble in the interstellar gas?

The velocity of the sun in its orbit around the galactic center is considered to be around what value?

What evidence do we have that there is hidden mass in the galaxy?

What keeps the matter in an HII region ionized?

In order to make a scale model of the galaxy in which stars are represented by salt grains,how far apart would neighboring salt grains be?

The stars in globular clusters are

The 21 cm line is emitted by

Journeys Start

Patterns in the Sky

Ancient Astronomy

Renaissance Astronomy

Gravity and Motion

Light and Telescopes

Overview of the Solar System

The Earth

The Moon

Mercury and Venus

Mars

Jupiter and Saturn

The Outer Solar System

Satellites

Small Solar System Bodies

Basic Properties of Stars

The Sun

The Formation of Stars and Planets

The Evolution of Stars

White Dwarfs, neutron Stars, and Black Holes

Binary Star Systems

Galaxies

Quasars and Other Active Galaxies

Galaxy Clusters and the Structure of the Universe

Cosmology

Life in the Universe

Filters