Question 1

The Rare Earth Hypothesis suggests that

Accepted Answer

A)  the circumstances that have allowed life on the Earth to appear and develop may be so rare that it is unlikely to have occurred anywhere else 
B)  Earth and life on it were created by some omnipotent being 
C)  the orbits of any Earth-like planets around other stars would have been disrupted by inward migration of Jovian planets 
D)  Earth-like planets are unlikely to have formed around any other stars

Question 2

Which of the following stars is the hottest?

Accepted Answer

A)  M7 
B)  A0 
C)  G6 
D)  B4

Question 3

At the lower left of the Hertzprung-Russell diagram we find

Accepted Answer

A)  supergiant stars 
B)  red giant stars 
C)  white dwarfs 
D)  main sequence stars

Question 4

When a star finally runs out of hydrogen to fuse in its central core

Accepted Answer

A)  it grows smaller and dimmer, becoming a brown dwarf 
B)  it grows larger and brighter, becoming a giant or supergiant star 
C)  it grows smaller and dimmer becoming a white dwarf 
D)  it remains the same size but grows brighter

Question 5

Why might it be difficult for Earth-like planets to form around Sun-like stars in the outer parts of the disk of our galaxy?

Accepted Answer

A)  there would be insufficient amounts of heavy elements 
B)  the stars would be packed together too densely for planets to be stable 
C)  any stars would be sucked into the central supermassive black hole 
D)  there would be too much harmful radiation

Question 6

Which method of extrasolar planet detection is able to measure the compositions of extrasolar planet atmopsheres?

Accepted Answer

A)  gravitational lensing 
B)  Doppler technique 
C)  transit technique 
D)  astrometric technique

Question 7

What parameters determine the position of a galaxy's Galactic Habitable Zone?

Accepted Answer

A)  only the amount of heavy elements in the disk 
B)  both the amount of heavy elements AND the amount of radiation from the center 
C)  only the temperature in the galactic disk 
D)  only the amount of harmful radiation from the center

Question 8

One of the fundamental principles of stellar evolution is that the more massive a star is

Accepted Answer

A)  the more heavy elements it contains 
B)  the more planets it has around it 
C)  the faster it evolves 
D)  the slower it evolves

Question 9

Brown dwarfs are

Accepted Answer

A)  stars in the process of forming 
B)  very cool, low mass stars of spectral type M 
C)  the burnt out cores of dead stars 
D)  objects with insufficient mass to sustain nuclear fusion in their cores

Question 10

Imagine we have a planet identical to Jupiter around another star, with the exception that its orbit is much closer. How would its density compare to Jupiter?

Accepted Answer

A)  it would be slightly higher 
B)  it would be much higher 
C)  it would be lower 
D)  it would be the same

Question 11

Why does the Doppler shift method of detecting extrasolar planets only give us the minimum mass of a planet?

Accepted Answer

A)  because we don't necessarily know the density of the planet 
B)  because we don't necessarily know the angle the planet's orbit makes with our line of sight 
C)  because we don't necessarily know the diameter (size) of the planet 
D)  because we don't necessarily know the mass of the parent star very

Question 12

If a star has an extrasolar planet, the wavelength of its radial velocity curve is related to the planet's

Accepted Answer

A)  orbital shape 
B)  radius 
C)  mass 
D)  orbital period

Question 13

Approximately what proportion of stars have masses lower than the Sun?

Accepted Answer

A)  90% 
B)  10% 
C)  50% 
D)  70%

Question 14

Multiple star systems in our galaxy

Accepted Answer

A)  are extremely rare, making up less than 1% of the total 
B)  are very common, making up about 50% of the total 
C)  are fairly common, making up around 30% of the total 
D)  do not exist

Question 15

When a low mass star like our Sun dies, it leaves behind a

Accepted Answer

A)  white dwarf 
B)  brown dwarf 
C)  neutron star 
D)  black hole

Question 16

If we are eventually able to detect Earth-like extrasolar planets directly, they will be seen very

Accepted Answer

A)  close to their parent stars and will be very dim in comparison 
B)  far from their parent stars and will be very dim in comparison 
C)  far from their parent stars and will be bright in comparison 
D)  close to their parent stars and will be bright in comparison

Question 17

What proportion of their lives do stars spend fusing hydrogen to helium in their cores?

Accepted Answer

A)  90% 
B)  70% 
C)  50% 
D)  10%

Question 18

Gravitational lensing is the process by which

Accepted Answer

A)  a massive object magnifies and distorts the light from an object behind it 
B)  the wavelengths of light from a star are shifted as it moves about its center of mass 
C)  a planet passes in front of its parent star and blocks part of its light 
D)  a massive object accelerates another object that passes close to it

Question 19

Many of the extrasolar planets that have been detected directly to date are

Accepted Answer

A)  very large and at great distances from their parent star 
B)  small and at great distances from their parent star 
C)  small and close to their parent star 
D)  very large and close to their parent star

Question 20

Which of the following extrasolar planets would be easiest to detect using the Doppler shift method?

Accepted Answer

A)  a massive planet far from its parent star 
B)  a low mass planet far from its parent star 
C)  a low mass planet close to its parent star 
D)  a massive planet close to its parent star

Exam 11: Extrasolar Planets: Their Nature and Potential Habitability