Question 1

The Voyager I and II spacecraft visited the Jovian planets in the 1980s. When will they reach the distances of the nearest stars?

Accepted Answer

A)   in our lifetime
B)   in our children's lifetime
C)   in our grandchildren's lifetime
D)   thousands of years from now
E)   hundreds of thousands of years from now

Question 2

Which of the following is not considered a potential solution to the question of why we lack any evidence of a galactic civilization?

Accepted Answer

A)   The galactic civilization probably is undetectable because they operate under different laws of physics from the ones we know.
B)   There is no galactic civilization because we are the first species ever to achieve the ability to study the universe.
C)   The galactic civilization is deliberately avoiding contact with us.
D)   There is no galactic civilization because all civilizations destroy themselves before they achieve the ability to colonize the galaxy.

Question 3

We have sent several spacecraft on trajectories that will ultimately take them into interstellar space (Pioneer 10 and 11, Voyager 1 and 2, New Horizons) . How long will it take these spacecraft to travel as far as the nearest stars?

Accepted Answer

A)   Tens of thousands of years
B)   A few hundred years
C)   A few decades
D)   Never, because they will rust and fall apart
E)   About a thousand years

Question 4

Evolution as a Scientific Theory: Detractors often dismiss evolution by emphasizing the role randomness plays in the theory. They argue that a living creature (such as a human being) is about as likely to have evolved by random chance as a Boeing 747 airplane is of being assembled by a tornado flying through a junkyard. Explain why this vivid analogy is nevertheless fundamentally flawed by correctly explaining the role that randomness plays in the theory of evolution.

Accepted Answer

The analogy comparing the likelihood of ...

Question 5

After Mars, the next most likely candidates for life in the solar system are

Accepted Answer

A)   Comets in the Oort cloud.
B)   The atmospheres of the Jovian planets.
C)   The large moons of the Jovian planets.
D)   The largest asteroids.
E)   Comets in the Kuiper-belt.

Question 6

Why do some scientists say that the Moon may have been important for the evolution of life on the Earth?

Accepted Answer

A)   It created the ocean tides, and life most likely started in tide pools.
B)   It stabilized the earth's axis tilt, preventing large climate changes.
C)   Meteorites from the Moon brought microscopic life to the Earth.
D)   It shielded the Earth during the heavy-bombardment phase of the early solar system.
E)   There is no known connection between the Moon and the evolution of life on the Earth.

Question 7

Which of the following is not a possible solution to the Fermi Paradox?

Accepted Answer

A)   We are the only intelligent civilization to have ever arisen in the Milky Way.
B)   Of all of the intelligent civilizations in the Milky Way, none has chosen to create a galactic civilization.
C)   There is a galactic civilization, but we are currently unable to detect or recognize it.
D)   There is a galactic civilization, but it is being actively hidden from us.
E)   Given the current age of our galaxy, there has not been enough time for a galactic civilization to develop.

Question 8

Briefly summarize current knowledge about the term f_life in the equation
Number of Civilizations = Np × $ f_{\mathrm{}} $life × $ f_{\mathrm{}} $civilization × $ f_{\mathrm{}} $ now

Accepted Answer

f_life is the fraction of habitable plan...

Question 9

How does the Kepler mission plan to detect Earth-like planets around other stars?

Accepted Answer

A)   by measuring the Doppler shift in spectral lines as the central star is tugged to and fro by the planet
B)   by observing the slight dip in brightness of the central star as the planet transits
C)   by directly imaging the planet in the infrared
D)   by observing the spectrum of the planet
E)   by measuring the slight shift in position of the central star as it is tugged to and fro by the planet

Question 10

Briefly summarize current knowledge about the term Np in the equation
Number of Civilizations = Np × $ f_{\mathrm{}} $life × $ f_{\mathrm{}} $civilization × $ f_{\mathrm{}} $ now.

Accepted Answer

Np is the number of planets in the Milky...

Question 11

Science Fiction as a Driver of Science? This chapter, more than any other in the book, involves familiar themes of science fiction: space travel, extraterrestrial life, extraterrestrial intelligence, and more. Give and discuss two concepts that started out as science fiction but ended up as science fact. Give and discuss an example of an idea from science fiction that will likely never be realized as science fact. Do you think that the rise in popularity of science fiction (Star Trek, Star Wars, and others) has increased or decreased the general public's understanding of science? Explain.

Accepted Answer

Two concepts that started out as science...

Question 12

Why are fossils of early life on Earth rarer than fossils of plants and animals from the past few hundred million years?

Accepted Answer

A)   Early organisms lacked skeletons and other hard structures that are most likely to be fossilized.
B)   Life was far less abundant prior to a few hundred million years ago.
C)   Fossils could not form before there was oxygen in the atmosphere.
D)   We find fossils in sedimentary layers, and no sediments were deposited until just a few hundred million years ago.

Question 13

How did oxygen (O₂)  get into Earth's atmosphere?

Accepted Answer

A)   It was released by life through the process of photosynthesis.
B)   It was captured from the solar nebula.
C)   It was outgassed from volcanoes.
D)   It came from chemical reactions with surface rocks.

Question 14

Briefly explain the meaning of each term in the equation
Number of Civilizations = Np ×  f_life × f_civilization × f_now.

Accepted Answer

Np is the number of planets in the Milky...

Question 15

Which of the following is considered by biologists to be a likely place where life might have first arisen on Earth?

Accepted Answer

A)   In hot water near undersea volcanoes
B)   On meteorites that landed on Earth
C)   On land surfaces that got moderately heavy rainfall
D)   Deep in Earth's core

Question 16

Which of the following describes a major danger of interstellar travel at near-light speed?

Accepted Answer

A)   Atoms and ions in interstellar space will hit a fast-moving spacecraft like a flood of dangerous cosmic rays.
B)   Any interstellar journey will take much longer than the lives of the crew members.
C)   Time dilation will slow the heart beats of the crew to a dangerously low rate.
D)   Asteroid fields floating in interstellar space will present a navigational challenge.

Question 17

Where have scientists begun an active search for life beyond the Earth?

Accepted Answer

A)   the Moon
B)   Venus
C)   Mars
D)   Europa
E)   Titan

Question 18

Why do some scientists think that Jupiter's existence may have been critical for life to evolve on Earth?

Accepted Answer

A)   It prevented the Earth from migrating outward and thus ensured a stable climate.
B)   It prevented the Earth from migrating inward and thus ensured a stable climate.
C)   It kicked out many comets from the inner solar system through gravitational encounters, thus ending the heavy bombardment phase of the solar system.
D)   Meteorites from Jupiter may have contained the bacteria that started life on Earth.
E)   It stabilized the Earth's axis tilt and thus ensured a stable climate.

Question 19

Which of the following is not considered crucial for life to exist on some world?

Accepted Answer

A)   Liquid water
B)   A source of energy that can be used by life
C)   A source of nutrients
D)   An atmosphere

Question 20

Suppose it turns out that one in 1 million stars has a planet that at some point in its history is home to an advanced civilization. Then the total number of civilizations that have arisen in our galaxy would be closest to ________.

Accepted Answer

A)   400,000
B)   40,000
C)   4,000
D)   400
E)   40

Exam 18: Life in the Universe

How did oxygen (O₂) get into Earth's atmosphere?

Correct Answer
verified

Briefly explain the meaning of each term in the equation Number of Civilizations = Np × f_life × f_civilization × f_now.

Correct Answer
verified
Np is the number of planets in the Milky...
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After Mars, the next most likely candidates for life in the solar system are

Correct Answer
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Which of the following is not considered crucial for life to exist on some world?

Correct Answer
verified

Which of the following is not a possible solution to the Fermi Paradox?

Correct Answer
verified

Correct Answer
Answered by ExamLex AI
The analogy comparing the likelihood of ...
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Correct Answer
Answered by ExamLex AI
Two concepts that started out as science...
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Why do some scientists think that Jupiter's existence may have been critical for life to evolve on Earth?

Correct Answer
verified

How does the Kepler mission plan to detect Earth-like planets around other stars?

Correct Answer
verified

Which of the following is not considered a potential solution to the question of why we lack any evidence of a galactic civilization?

Correct Answer
verified

Why do some scientists say that the Moon may have been important for the evolution of life on the Earth?

Correct Answer
verified

Suppose it turns out that one in 1 million stars has a planet that at some point in its history is home to an advanced civilization. Then the total number of civilizations that have arisen in our galaxy would be closest to ________.

Correct Answer
verified

Why are fossils of early life on Earth rarer than fossils of plants and animals from the past few hundred million years?

Correct Answer
verified

We have sent several spacecraft on trajectories that will ultimately take them into interstellar space (Pioneer 10 and 11, Voyager 1 and 2, New Horizons) . How long will it take these spacecraft to travel as far as the nearest stars?

Correct Answer
verified

Briefly summarize current knowledge about the term f_life in the equation Number of Civilizations = Np × $f_{\mathrm{}}$ life × $f_{\mathrm{}}$ civilization × $f_{\mathrm{}}$ now

Correct Answer
verified
f_life is the fraction of habitable plan...
View Answer

Where have scientists begun an active search for life beyond the Earth?

Correct Answer
verified

The Voyager I and II spacecraft visited the Jovian planets in the 1980s. When will they reach the distances of the nearest stars?

Correct Answer
verified

Which of the following describes a major danger of interstellar travel at near-light speed?

Correct Answer
verified

Which of the following is considered by biologists to be a likely place where life might have first arisen on Earth?

Correct Answer
verified

Briefly summarize current knowledge about the term Np in the equation Number of Civilizations = Np × $f_{\mathrm{}}$ life × $f_{\mathrm{}}$ civilization × $f_{\mathrm{}}$ now.

Correct Answer
verified
Np is the number of planets in the Milky...
View Answer

Exam 18: Life in the Universe

How did oxygen (O₂) get into Earth's atmosphere?

Correct AnswerverifiedShow Answer

Briefly explain the meaning of each term in the equation Number of Civilizations = Np × f_life × f_civilization × f_now.

Correct AnswerverifiedNp is the number of planets in the Milky...View AnswerShow Answer

After Mars, the next most likely candidates for life in the solar system are

Correct AnswerverifiedShow Answer

Which of the following is not considered crucial for life to exist on some world?

Correct AnswerverifiedShow Answer

Which of the following is not a possible solution to the Fermi Paradox?

Correct AnswerverifiedShow Answer

Correct AnswerAnswered by ExamLex AIThe analogy comparing the likelihood of ...View AnswerShow Answer

Correct AnswerAnswered by ExamLex AITwo concepts that started out as science...View AnswerShow Answer

Why do some scientists think that Jupiter's existence may have been critical for life to evolve on Earth?

Correct AnswerverifiedShow Answer

How does the Kepler mission plan to detect Earth-like planets around other stars?

Correct AnswerverifiedShow Answer

Which of the following is not considered a potential solution to the question of why we lack any evidence of a galactic civilization?

Correct AnswerverifiedShow Answer

Why do some scientists say that the Moon may have been important for the evolution of life on the Earth?

Correct AnswerverifiedShow Answer

Suppose it turns out that one in 1 million stars has a planet that at some point in its history is home to an advanced civilization. Then the total number of civilizations that have arisen in our galaxy would be closest to ________.

Correct AnswerverifiedShow Answer

Why are fossils of early life on Earth rarer than fossils of plants and animals from the past few hundred million years?

Correct AnswerverifiedShow Answer

We have sent several spacecraft on trajectories that will ultimately take them into interstellar space (Pioneer 10 and 11, Voyager 1 and 2, New Horizons) . How long will it take these spacecraft to travel as far as the nearest stars?

Correct AnswerverifiedShow Answer

Briefly summarize current knowledge about the term f_life in the equation Number of Civilizations = Np × f f_{\mathrm{}} f​ life × f f_{\mathrm{}} f​ civilization × f f_{\mathrm{}} f​ now

Correct Answerverifiedf_life is the fraction of habitable plan...View AnswerShow Answer

Where have scientists begun an active search for life beyond the Earth?

Correct AnswerverifiedShow Answer

The Voyager I and II spacecraft visited the Jovian planets in the 1980s. When will they reach the distances of the nearest stars?

Correct AnswerverifiedShow Answer

Which of the following describes a major danger of interstellar travel at near-light speed?

Correct AnswerverifiedShow Answer

Which of the following is considered by biologists to be a likely place where life might have first arisen on Earth?

Correct AnswerverifiedShow Answer

Briefly summarize current knowledge about the term Np in the equation Number of Civilizations = Np × f f_{\mathrm{}} f​ life × f f_{\mathrm{}} f​ civilization × f f_{\mathrm{}} f​ now.

Correct AnswerverifiedNp is the number of planets in the Milky...View AnswerShow Answer

Correct Answer
verified

Correct Answer
verified
Np is the number of planets in the Milky...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
Answered by ExamLex AI
The analogy comparing the likelihood of ...
View Answer

Correct Answer
Answered by ExamLex AI
Two concepts that started out as science...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Briefly summarize current knowledge about the term f_life in the equation Number of Civilizations = Np × $f_{\mathrm{}}$ life × $f_{\mathrm{}}$ civilization × $f_{\mathrm{}}$ now

Correct Answer
verified
f_life is the fraction of habitable plan...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Briefly summarize current knowledge about the term Np in the equation Number of Civilizations = Np × $f_{\mathrm{}}$ life × $f_{\mathrm{}}$ civilization × $f_{\mathrm{}}$ now.

Correct Answer
verified
Np is the number of planets in the Milky...
View Answer