Question 1

What are scientists' best guess(es) for the requirement(s) of life?

Accepted Answer

A)  a source of materials (nutrients) 
B)  energy to fuel the activities of life
C)  liquid water
D)  all of the aboveE) A) and B)
F) A) and C)

Question 2

Einstein's theory of relativity tells us that travelers who make a high- speed trip to a distant star and back will .

Accepted Answer

A)  have more fun than people who stay behind on Earth
B)  never be able to make the trip within their lifetimes
C)  age more than people who stay behind on Earth
D)  age less than people who stay behind on EarthE) B) and C)
F) A) and D)

Question 3

We have already launched spacecraft whose orbits will carry into interstellar space.

Accepted Answer

A) True 
 B)False

Question 4

The only place outside of Earth for which there is irrefutable evidence for ancient, microbial life is

Accepted Answer

A)  Titan.
B)  Europa.
C)  Mars.
D)  the Moon.
E)  None of the above-there is no irrefutable evidence for life beyond Earth.F) None of the above
G) C) and E)

Question 5

Which of the following best describes the predominant scientific view of the origin of life on Earth?

Accepted Answer

A)  Life probably migrated to Earth from some other world.
B)  We may never know precisely how life arose, but current evidence suggests that life probably can arise naturally under the conditions that prevailed on the early Earth.
C)  Life arose through a series of extremely unlikely chemical coincidences, making it seem almost miraculous that life ever came to exist at all.
D)  We can describe with great certainty the precise steps by which life arose on Earth.E) B) and C)
F) A) and C)

Question 6

Briefly explain the Fermi Paradox, namely the paradox of the question "Where are the aliens?"

Accepted Answer

If we survive and decide to become inter...

Question 7

The modern- day organisms that seem oldest, in an evolutionary sense, are microbes that live in the hot water around volcanic vents on the ocean floor.

Accepted Answer

A) True 
 B)False

Question 8

The figure above shows the geological times scale. Life has existed for of the Earth's history.

Accepted Answer

A)  about 1/2
B)  about 1/4
C)  about 9/10
D)  allE) All of the above
F) C) and D)

Question 9

The Pioneer and Voyager spacecraft carry a message from Earth, just in case an alien civilization ever runs across them.

Accepted Answer

A) True 
 B)False

Question 10

Which of the following best describes what we mean by a habitable world?

Accepted Answer

A)  a planet or moon that lies within its star's habitable zone
B)  a planet or moon on which humans could survive if we happened to go there
C)  a planet or moon that could support life, if any life happened to be on it
D)  a planet or moon with lifeE) B) and C)
F) None of the above

Question 11

Why do scientists say that evolution is a "theory"?

Accepted Answer

A)  because it explains a great deal about life and is supported by an enormous body of evidence
B)  because it's really just a guess about how life developed on Earth
C)  because it is supported by only a small amount of evidence
D)  because they are not very confident that it really happenedE) C) and D)
F) A) and B)

Question 12

What defines the habitable zone around a star?

Accepted Answer

A)  the region around a star where rocky planets can form
B)  the region around a star outside of its hot, tenuous corona
C)  the region around a star where its ultraviolet radiation is too weak to destroy biological organisms on a planetary surface
D)  the region around a star where liquid water can exist on planetary surfaces
E)  the region around a star where humans can surviveF) B) and E)
G) A) and B)

Question 13

The figure above shows the geological times scale. Animals have been present on land for approximately _ of the Earth's history.

Accepted Answer

A)  3/4
B)  1/5
C)  1/2
D)  1/10E) C) and D)
F) A) and B)

Question 14

What is a mutation?

Accepted Answer

A)  a change in the physical appearance of a living organism
B)  a change in a living cell's DNA
C)  a change in the type of food an organism consumes
D)  a change in an organism that turns it into a different speciesE) A) and B)
F) C) and D)

Question 15

We are not yet capable of detecting life on planets around other stars. But as our technology develops, our first real chance of detecting such life will probably come from .

Accepted Answer

A)  sending spacecraft to study the planets up close
B)  determining the orbital properties of the planets
C)  examining spectral lines from the atmospheres of distant planets
D)  examining high- resolution images of the planets made by orbiting telescopesE) None of the above
F) All of the above

Question 16

Briefly explain the purpose of the equation
Number of Civilizations = NHP × flife × fcivilization × fnow.

Accepted Answer

This equation is used to estim...

Question 17

Which of the following best explains why an interstellar ramjet could, in theory, achieve continuous acceleration?

Accepted Answer

A)  It has such a large fuel tank that it will essentially never use up all the fuel it carries.
B)  It takes advantage of theoretically possible loopholes in Einstein's theory of relativity.
C)  It uses fuel that is more efficient than any other known fuel.
D)  Its speed always gets faster because time dilation changes the rate at which time flows.
E)  It collects its fuel as it goes, rather than having to carry the weight of fuel along with it.F) B) and D)
G) A) and E)

Question 18

The habitable zone around a star refers to the places where living organisms are found.

Accepted Answer

A) True 
 B)False

Question 19

Which of the following statements best reflects our current knowledge about the term flife in the equation Number of Civilizations = NHP × flife × fcivilization × fnow?

Accepted Answer

A)  The value of flife is less than 0.0000001.
B)  The value of flife is greater than 10.
C)  The value of flife is between 0 and 1.
D)  The value of flife is equal to 1/2.
E)  The value of flife is either 0 or 1.F) C) and D)
G) B) and E)

Question 20

In 1974, a radio message was sent out from the Arecibo observatory in Puerto Rico towards a globular cluster, 21,000 light- years away. Approximately how far has this message gotten as of today?

Accepted Answer

A)  It's just beyond the Neptune in our solar system
B)  It's already arrived at the globular cluster.
C)  It's just passing through the Oort cloud surrounding our solar system
D)  It's almost at the center of the Milky Way.
E)  It's just passing stars that are close neighbors to the Sun in the Milky Way.F) None of the above
G) B) and D)

Exam 19: Life in the Universe

We are not yet capable of detecting life on planets around other stars. But as our technology develops, our first real chance of detecting such life will probably come from .

Correct AnswerverifiedShow Answer

Briefly explain the purpose of the equation Number of Civilizations = NHP × flife × fcivilization × fnow.

Correct AnswerverifiedThis equation is used to estim...View AnswerShow Answer

The habitable zone around a star refers to the places where living organisms are found.

Correct AnswerverifiedShow Answer

The only place outside of Earth for which there is irrefutable evidence for ancient, microbial life is

Correct AnswerverifiedShow Answer

Which of the following best describes what we mean by a habitable world?

Correct AnswerverifiedShow Answer

What defines the habitable zone around a star?

Correct AnswerverifiedShow Answer

Einstein's theory of relativity tells us that travelers who make a high- speed trip to a distant star and back will .

Correct AnswerverifiedShow Answer

What is a mutation?

Correct AnswerverifiedShow Answer

The Pioneer and Voyager spacecraft carry a message from Earth, just in case an alien civilization ever runs across them.

Correct AnswerverifiedShow Answer

We have already launched spacecraft whose orbits will carry into interstellar space.

Correct AnswerverifiedShow Answer

What are scientists' best guess(es) for the requirement(s) of life?

Correct AnswerverifiedShow Answer

Briefly explain the Fermi Paradox, namely the paradox of the question "Where are the aliens?"

Correct AnswerverifiedIf we survive and decide to become inter...View AnswerShow Answer

Which of the following best describes the predominant scientific view of the origin of life on Earth?

Correct AnswerverifiedShow Answer

In 1974, a radio message was sent out from the Arecibo observatory in Puerto Rico towards a globular cluster, 21,000 light- years away. Approximately how far has this message gotten as of today?

Correct AnswerverifiedShow Answer

Why do scientists say that evolution is a "theory"?

Correct AnswerverifiedShow Answer

The figure above shows the geological times scale. Life has existed for of the Earth's history.

Correct AnswerverifiedShow Answer

The figure above shows the geological times scale. Animals have been present on land for approximately _ of the Earth's history.

Correct AnswerverifiedShow Answer

Which of the following statements best reflects our current knowledge about the term flife in the equation Number of Civilizations = NHP × flife × fcivilization × fnow?

Correct AnswerverifiedShow Answer

Which of the following best explains why an interstellar ramjet could, in theory, achieve continuous acceleration?

Correct AnswerverifiedShow Answer

The modern- day organisms that seem oldest, in an evolutionary sense, are microbes that live in the hot water around volcanic vents on the ocean floor.

Correct AnswerverifiedShow Answer

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This equation is used to estim...
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If we survive and decide to become inter...
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