Question 1

If distance from the Sun were the only factor affecting surface habitability, which of the following would be habitable?

Accepted Answer

A)  the Moon 
B)  Venus 
C)  Mercury 
D)  all of these 
A)  the Moon 
B)  Venus 
C)  Mercury 
D)  all of these A

Question 2

If Mars had a thicker atmosphere with a strong greenhouse effect, the outer boundary of the Sun's habitable zone would lie

Accepted Answer

A)  roughly halfway between the orbit of the Earth and Mars 
B)  just within the orbit of Mars 
C)  roughly halfway between the orbit of Mars and Jupiter 
D)  just beyond the orbit of Mars 
A)  roughly halfway between the orbit of the Earth and Mars 
B)  just within the orbit of Mars 
C)  roughly halfway between the orbit of Mars and Jupiter 
D)  just beyond the orbit of Mars D

Question 3

Climate models which ignore human activity

Accepted Answer

A)  completely fail to match real climate data 
B)  match real climate data quite well 
C)  match real climate data perfectly 
D)  match real climate data, but only poorly 
A)  completely fail to match real climate data 
B)  match real climate data quite well 
C)  match real climate data perfectly 
D)  match real climate data, but only poorly A

Question 4

Evidence that the recent rise in carbon dioxide concentration is due to human activity and not natural factors comes from

Accepted Answer

A)  the amount of the rise in the atmospheric concentration tracks almost perfectly with the amount of carbon dioxide being released by industry 
B)  estimates of changes in the amount of carbon dioxide from natural sources such as volcanoes and the oceans can account for no more than about 1% of the rise in the atmospheric concentration 
C)  the ratio of carbon isotopes is consistent with the increase in carbon dioxide levels coming primarily from the burning of fossil fuels 
D)  all of these constitute evidence 
A)  the amount of the rise in the atmospheric concentration tracks almost perfectly with the amount of carbon dioxide being released by industry 
B)  estimates of changes in the amount of carbon dioxide from natural sources such as volcanoes and the oceans can account for no more than about 1% of the rise in the atmospheric concentration 
C)  the ratio of carbon isotopes is consistent with the increase in carbon dioxide levels coming primarily from the burning of fossil fuels 
D)  all of these constitute evidence

Question 5

When Venus first formed it had large quantities of water vapor in its atmosphere while today only very low levels of water are present. Where did most of the water vapor go?

Accepted Answer

A)  it was destroyed in the atmosphere by ultraviolet light from the Sun 
B)  it became chemically incorporated into rocks in the crust 
C)  it was blasted into space by impacts 
D)  it escaped into space 
A)  it was destroyed in the atmosphere by ultraviolet light from the Sun 
B)  it became chemically incorporated into rocks in the crust 
C)  it was blasted into space by impacts 
D)  it escaped into space

Question 6

Which of the following provides evidence for active volcanism on Venus today and in the past?

Accepted Answer

A)  the direct observation of erupting volcanoes from orbit 
B)  the presence of sulfuric acid clouds in the atmosphere 
C)  the detection from orbit of elevated levels of infrared radiation from volcanic features on the surface 
D)  Both B and C 
A)  the direct observation of erupting volcanoes from orbit 
B)  the presence of sulfuric acid clouds in the atmosphere 
C)  the detection from orbit of elevated levels of infrared radiation from volcanic features on the surface 
D)  Both B and C

Question 7

When the Sun was younger, how did its habitable zone compare with its habitable zone today?

Accepted Answer

A)  narrower and closer to the Sun 
B)  narrower and farther from the Sun 
C)  wider and closer to the Sun 
D)  wider and farther from the Sun 
A)  narrower and closer to the Sun 
B)  narrower and farther from the Sun 
C)  wider and closer to the Sun 
D)  wider and farther from the Sun

Question 8

Venus is located

Accepted Answer

A)  near the outer boundary of the Sun's habitable zone 
B)  in the middle of the Sun's habitable zone 
C)  near the inner boundary of the Sun's habitable zone 
D)  outside the Sun's habitable zone 
A)  near the outer boundary of the Sun's habitable zone 
B)  in the middle of the Sun's habitable zone 
C)  near the inner boundary of the Sun's habitable zone 
D)  outside the Sun's habitable zone

Question 9

What is the definition of a star's habitable zone?

Accepted Answer

A)  the range of distances from the star where planets with life have been detected 
B)  the range of distances from the star where rocky planets can form 
C)  the range of distances from the star where organic molecules can be stable on the surface of a suitable planet 
D)  the range of distances from the star where liquid water can be stable on the surface of a suitable planet 
A)  the range of distances from the star where planets with life have been detected 
B)  the range of distances from the star where rocky planets can form 
C)  the range of distances from the star where organic molecules can be stable on the surface of a suitable planet 
D)  the range of distances from the star where liquid water can be stable on the surface of a suitable planet

Question 10

Around 4 billion years ago Venus could have been more Earth-like with liquid water on its surface because

Accepted Answer

A)  Venus has a protective magnetic field 
B)  its atmosphere was thinner 
C)  Venus was farther from the Sun 
D)  the Sun was dimmer so Venus would have received less radiation 
A)  Venus has a protective magnetic field 
B)  its atmosphere was thinner 
C)  Venus was farther from the Sun 
D)  the Sun was dimmer so Venus would have received less radiation

Question 11

Stars much more luminous than the Sun have

Accepted Answer

A)  narrower habitable zones, decreasing the odds of finding habitable planets and lifetimes too short for life to appear 
B)  wider habitable zones, increasing the odds of finding habitable planets but lifetimes too short for life to appear 
C)  narrower habitable zones, decreasing the odds of finding habitable planets but much longer lifetimes allowing life to appear and evolve 
D)  wider habitable zones, increasing the odds of finding habitable planets and much longer lifetimes allowing life to appear and evolve 
A)  narrower habitable zones, decreasing the odds of finding habitable planets and lifetimes too short for life to appear 
B)  wider habitable zones, increasing the odds of finding habitable planets but lifetimes too short for life to appear 
C)  narrower habitable zones, decreasing the odds of finding habitable planets but much longer lifetimes allowing life to appear and evolve 
D)  wider habitable zones, increasing the odds of finding habitable planets and much longer lifetimes allowing life to appear and evolve

Question 12

The recent gradual rise in the Earth's average surface temperature is commonly referred to as

Accepted Answer

A)  global warming 
B)  the greenhouse effect 
C)  ozone depletion 
D)  global heating 
A)  global warming 
B)  the greenhouse effect 
C)  ozone depletion 
D)  global heating

Question 13

Europa is located outside the Sun's habitable zone and yet may be habitable. How can this be?

Accepted Answer

A)  Europa's subsurface ocean contains lots of minerals that allow water to remain liquid at much lower temperatures 
B)  Europa is continually being hit by comets and asteroids which keeps water beneath its surface liquid 
C)  Europa is tidally heated, allowing liquid water to exist beneath its icy surface 
D)  Europa is large enough to have appreciable heat trapped inside it to keep water beneath the surface liquid 
A)  Europa's subsurface ocean contains lots of minerals that allow water to remain liquid at much lower temperatures 
B)  Europa is continually being hit by comets and asteroids which keeps water beneath its surface liquid 
C)  Europa is tidally heated, allowing liquid water to exist beneath its icy surface 
D)  Europa is large enough to have appreciable heat trapped inside it to keep water beneath the surface liquid

Question 14

The minimum size that makes it possible for a planetary surface to remain habitable over long time periods is a size that allows

Accepted Answer

A)  plate tectonics to be present 
B)  a magnetic field to be present 
C)  an atmosphere to be present 
D)  hot spot volcanism to be present 
A)  plate tectonics to be present 
B)  a magnetic field to be present 
C)  an atmosphere to be present 
D)  hot spot volcanism to be present

Question 15

Today, global average temperatures are estimated using

Accepted Answer

A)  orbiting satellites 
B)  weather stations 
C)  water temperature measurements by ships 
D)  all of these 
A)  orbiting satellites 
B)  weather stations 
C)  water temperature measurements by ships 
D)  all of these

Question 16

Evidence for the loss of water from the atmosphere of Venus via the action of ultraviolet light comes from the

Accepted Answer

A)  observation of auroras high in the Venusian atmosphere caused by the action of ultraviolet light on water molecules 
B)  fact that today, water is found only in the upper atmosphere of Venus 
C)  observation of an ozone layer in the atmosphere which is formed from the breakup of water molecules by ultraviolet radiation 
D)  observation of an excess of heavy hydrogen (deuterium) atoms in the atmosphere which are less easily able to escape once the water is broken apart 
A)  observation of auroras high in the Venusian atmosphere caused by the action of ultraviolet light on water molecules 
B)  fact that today, water is found only in the upper atmosphere of Venus 
C)  observation of an ozone layer in the atmosphere which is formed from the breakup of water molecules by ultraviolet radiation 
D)  observation of an excess of heavy hydrogen (deuterium) atoms in the atmosphere which are less easily able to escape once the water is broken apart

Question 17

A star less luminous than our Sun will have a habitable zone that is

Accepted Answer

A)  narrower and closer to the star than the habitable zone of the Sun 
B)  wider and closer to the star than the habitable zone of the Sun 
C)  narrower and farther from the star than the habitable zone of the Sun 
D)  wider and farther from the star than the habitable zone of the Sun 
A)  narrower and closer to the star than the habitable zone of the Sun 
B)  wider and closer to the star than the habitable zone of the Sun 
C)  narrower and farther from the star than the habitable zone of the Sun 
D)  wider and farther from the star than the habitable zone of the Sun

Question 18

The atmospheric carbon dioxide concentration

Accepted Answer

A)  is higher than it has been at any time during the last 800,000 years 
B)  is higher than it has been at any time during the Earth's history 
C)  has remained roughly constant during the last 800,000 years 
D)  is lower than it has been at any time during the last 800,000 years 
A)  is higher than it has been at any time during the last 800,000 years 
B)  is higher than it has been at any time during the Earth's history 
C)  has remained roughly constant during the last 800,000 years 
D)  is lower than it has been at any time during the last 800,000 years

Question 19

Most of the carbon dioxide on Venus

Accepted Answer

A)  is trapped beneath the surface of the planet in gaseous form 
B)  has escaped into space 
C)  is present in its atmosphere 
D)  is locked up in carbonate rocks in its crust 
A)  is trapped beneath the surface of the planet in gaseous form 
B)  has escaped into space 
C)  is present in its atmosphere 
D)  is locked up in carbonate rocks in its crust

Question 20

Although low luminosity stars are very common, the probability of individual stars having planets within their habitable zones is low because low luminosity stars

Accepted Answer

A)  are not expected to form rocky, terrestrial planets 
B)  have very narrow habitable zones 
C)  have no habitable zones at all 
D)  are very unstable 
A)  are not expected to form rocky, terrestrial planets 
B)  have very narrow habitable zones 
C)  have no habitable zones at all 
D)  are very unstable

If distance from the Sun were the only factor affecting surface habitability, which of the following would be habitable?

If Mars had a thicker atmosphere with a strong greenhouse effect, the outer boundary of the Sun's habitable zone would lie

Climate models which ignore human activity

Evidence that the recent rise in carbon dioxide concentration is due to human activity and not natural factors comes from

When Venus first formed it had large quantities of water vapor in its atmosphere while today only very low levels of water are present. Where did most of the water vapor go?

Which of the following provides evidence for active volcanism on Venus today and in the past?

When the Sun was younger, how did its habitable zone compare with its habitable zone today?

Venus is located

What is the definition of a star's habitable zone?

Around 4 billion years ago Venus could have been more Earth-like with liquid water on its surface because

Stars much more luminous than the Sun have

The recent gradual rise in the Earth's average surface temperature is commonly referred to as

Europa is located outside the Sun's habitable zone and yet may be habitable. How can this be?

The minimum size that makes it possible for a planetary surface to remain habitable over long time periods is a size that allows

Today, global average temperatures are estimated using

Evidence for the loss of water from the atmosphere of Venus via the action of ultraviolet light comes from the

A star less luminous than our Sun will have a habitable zone that is

The atmospheric carbon dioxide concentration

Most of the carbon dioxide on Venus

Although low luminosity stars are very common, the probability of individual stars having planets within their habitable zones is low because low luminosity stars

A Universe of Life

The Science of Life in the Universe

The Universal Context of Life

The Habitability of Earth

The Nature of Life on Earth

The Origin and Evolution of Life on Earth

Searching for Life in Our Solar System

Mars

Life on Jovian Moons

Extrasolar Planets: Their Nature and Potential Habitability

The Search for Extraterrestrial Intelligence

Interstellar Travel and the Fermi Paradox

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Exam 10: The Nature and Evolution of Habitability

If distance from the Sun were the only factor affecting surface habitability, which of the following would be habitable?

If Mars had a thicker atmosphere with a strong greenhouse effect, the outer boundary of the Sun's habitable zone would lie

Climate models which ignore human activity

Evidence that the recent rise in carbon dioxide concentration is due to human activity and not natural factors comes from

When Venus first formed it had large quantities of water vapor in its atmosphere while today only very low levels of water are present. Where did most of the water vapor go?

Which of the following provides evidence for active volcanism on Venus today and in the past?

When the Sun was younger, how did its habitable zone compare with its habitable zone today?

Venus is located

What is the definition of a star's habitable zone?

Around 4 billion years ago Venus could have been more Earth-like with liquid water on its surface because

Stars much more luminous than the Sun have

The recent gradual rise in the Earth's average surface temperature is commonly referred to as

Europa is located outside the Sun's habitable zone and yet may be habitable. How can this be?

The minimum size that makes it possible for a planetary surface to remain habitable over long time periods is a size that allows

Today, global average temperatures are estimated using

Evidence for the loss of water from the atmosphere of Venus via the action of ultraviolet light comes from the

A star less luminous than our Sun will have a habitable zone that is

The atmospheric carbon dioxide concentration

Most of the carbon dioxide on Venus

Although low luminosity stars are very common, the probability of individual stars having planets within their habitable zones is low because low luminosity stars

A Universe of Life

The Science of Life in the Universe

The Universal Context of Life

The Habitability of Earth

The Nature of Life on Earth

The Origin and Evolution of Life on Earth

Searching for Life in Our Solar System

Mars

Life on Jovian Moons

Extrasolar Planets: Their Nature and Potential Habitability

The Search for Extraterrestrial Intelligence

Interstellar Travel and the Fermi Paradox

Filters