Question 1

Most neutron stars are the remnants of _____ explosions.

Accepted Answer

A)  type II supernovae 
B)  type Ia supernovae 
C)  type Ib supernovae 
D)  novae 
E)  planetary nebulae 
A)  type II supernovae 
B)  type Ia supernovae 
C)  type Ib supernovae 
D)  novae 
E)  planetary nebulae A

Question 2

Explain the "Lighthouse Model" of pulsars.

Accepted Answer

A neutron star has a very strong magnetic field and spins very rapidly. The strong electrical and magnetic fields of the neutron star create powerful beams of high-energy radiation emerging from the magnetic poles of the neutron star. 
The neutron star rotates around its axis, but its axis also rotates, sweeping these beams of rotation through space - much like the light beams from a lighthouse. When the beam is directed in the direction of Earth, a pulse of energy is detected. The beam quickly moves away, and is not detected from Earth.

Question 3

When viewed from nearby, a black hole in empty space _____.

Accepted Answer

A)  has a funnel shape, extending to the event horizon 
B)  glows in X-rays and gamma-rays from superheated surface 
C)  is invisible 
D)  would look like a dark sphere the size of Earth 
E)  emits blackbody radiation only 
A)  has a funnel shape, extending to the event horizon 
B)  glows in X-rays and gamma-rays from superheated surface 
C)  is invisible 
D)  would look like a dark sphere the size of Earth 
E)  emits blackbody radiation only C

Question 4

A compact object emitting very regularly spaced bursts of radio energy is known as a(n) _______________.

Accepted Answer

The answer of A compact object emitting very regularly spaced...

Question 5

A compact object with a mass of 4 solar masses must be a black hole.

Accepted Answer

A) True 
 B)False

Question 6

Pulsar planets are _____.

Accepted Answer

A)  huge gas planets that could be classified as brown dwarfs 
B)  asteroids captured from interstellar space 
C)  observed, but not fully understood 
D)  predicted, but have not been observed 
E)  Earth-like, and may harbor life 
A)  huge gas planets that could be classified as brown dwarfs 
B)  asteroids captured from interstellar space 
C)  observed, but not fully understood 
D)  predicted, but have not been observed 
E)  Earth-like, and may harbor life

Question 7

Why are millisecond pulsars often found in binary systems with small red- or brown-dwarf companions?

Accepted Answer

A normal pulsar has a period of a few te

Question 8

A stellar core with a mass greater than 3 solar masses will collapse until it reaches _____.

Accepted Answer

A)  the radiusof Earth 
B)  the radius of Mt. Everest 
C)  the radius of a grain of sand. 
D)  the radius of a helium atom 
E)  a radius of zero 
A)  the radiusof Earth 
B)  the radius of Mt. Everest 
C)  the radius of a grain of sand. 
D)  the radius of a helium atom 
E)  a radius of zero

Question 9

Schwarzschild showed how the _______________ of the event horizon depends only on the mass of the black hole.

Accepted Answer

The answer of Schwarzschild showed how the _______________ of the...

Question 10

A hypernova is one of several types of events that create a gamma ray burst.

Accepted Answer

A) True 
 B)False

Question 11

Gamma ray bursts are ____.

Accepted Answer

A)  too weak to affect life on Earth 
B)  an important influence on mutation and evolution 
C)  the cause of the spectacular auroras at high latitudes 
D)  triggers for solar flares and coronal mass ejections 
E)  capable of causing mass extinction events 
A)  too weak to affect life on Earth 
B)  an important influence on mutation and evolution 
C)  the cause of the spectacular auroras at high latitudes 
D)  triggers for solar flares and coronal mass ejections 
E)  capable of causing mass extinction events

Question 12

The highest luminosity burst of radiation observed from a pulsar is the result of _____.

Accepted Answer

A)  the pulsation of a neutron star's surface 
B)  a "hot spot" that rotates around the equator of a pulsar 
C)  a spinning beam of radiation emerging from the pulsar's poles 
D)  the rotation of an accretion disk transferring matter to the pulsar's surface 
E)  the revolution of a binary companion that eclipses the pulsar, then reveals it 
A)  the pulsation of a neutron star's surface 
B)  a "hot spot" that rotates around the equator of a pulsar 
C)  a spinning beam of radiation emerging from the pulsar's poles 
D)  the rotation of an accretion disk transferring matter to the pulsar's surface 
E)  the revolution of a binary companion that eclipses the pulsar, then reveals it

Question 13

What observational properties of pulsars allowed astronomers to discover them as a new type of object?

Accepted Answer

A pulsar emits a very regular pattern of

Question 14

Most pulsars _____.

Accepted Answer

A)  speed up their rotation as they age 
B)  become more luminous as they age 
C)  emit lower energy radiation as they age 
D)  emit higher energy radiation as they age 
E)  slow downtheir rotation as they age 
A)  speed up their rotation as they age 
B)  become more luminous as they age 
C)  emit lower energy radiation as they age 
D)  emit higher energy radiation as they age 
E)  slow downtheir rotation as they age

Question 15

The event horizon of a black hole is the point where _____.

Accepted Answer

A)  the mass of the black hole is concentrated in a singularity 
B)  the accretion disk around the black hole contacts its surface 
C)  the escape velocity equals the speed of light 
D)  tidal forces ionize infalling gas 
E)  an infalling particle reaches equilibrium with radiation pressure 
A)  the mass of the black hole is concentrated in a singularity 
B)  the accretion disk around the black hole contacts its surface 
C)  the escape velocity equals the speed of light 
D)  tidal forces ionize infalling gas 
E)  an infalling particle reaches equilibrium with radiation pressure

Question 16

The orbits of binary pulsars will get smaller because of _______________ radiation.

Accepted Answer

The answer of The orbits of binary pulsars will get...

Question 17

Imagine an astronaut falling into a black hole. Describe the effects that the astronaut would experience firsthand, and the changes that an external observer would see.

Accepted Answer

The astronaut would notice that initiall

Question 18

Why do some supernovae form neutron star remnants instead of white dwarfs?

Accepted Answer

The Chandrasekhar limit specifies that t

Question 19

Astronomers detect _______________ of ionized gas moving perpendicular to the plane of many accretion disks.

Accepted Answer

The answer of Astronomers detect _______________ of ionized gas moving...

Question 20

Many pulsars are not associated with supernova remnants.

Accepted Answer

A) True 
 B)False

Exam 14: Neutron Stars and Black Holes

Most neutron stars are the remnants of _____ explosions.

Explain the "Lighthouse Model" of pulsars.

When viewed from nearby, a black hole in empty space _____.

A compact object emitting very regularly spaced bursts of radio energy is known as a(n) _______________.

A compact object with a mass of 4 solar masses must be a black hole.

Pulsar planets are _____.

Why are millisecond pulsars often found in binary systems with small red- or brown-dwarf companions?

A stellar core with a mass greater than 3 solar masses will collapse until it reaches _____.

Schwarzschild showed how the _______________ of the event horizon depends only on the mass of the black hole.

A hypernova is one of several types of events that create a gamma ray burst.

Gamma ray bursts are ____.

The highest luminosity burst of radiation observed from a pulsar is the result of _____.

What observational properties of pulsars allowed astronomers to discover them as a new type of object?

Most pulsars _____.

The event horizon of a black hole is the point where _____.

The orbits of binary pulsars will get smaller because of _______________ radiation.

Imagine an astronaut falling into a black hole. Describe the effects that the astronaut would experience firsthand, and the changes that an external observer would see.

Why do some supernovae form neutron star remnants instead of white dwarfs?

Astronomers detect _______________ of ionized gas moving perpendicular to the plane of many accretion disks.

Many pulsars are not associated with supernova remnants.

Here and Now

A Users Guide to the Sky

Moon Phases and Eclipses

Origins of Modern Astronomy

Gravity

Light and Telescopes

Atoms and Spectra

The Sun

The Family of Stars

The Interstellar Medium

Formation and Structure of Stars

Stellar Evolution

Deaths of Stars

The Milky Way Galaxy

Galaxies

Supermassive Black Holes and Active Galaxies

Modern Cosmology

Origin of the Solar System and Extrasolar Planets

Earth the Active Planet

The Moon and Mercury

Venus and Mars

Jupiter and Saturn

Uranus Neptune Pluto and the Kuiper Belt

Meteorites Asteroids and Comets

Astrobiology

Filters