Question 1

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

Accepted Answer

A) True 
 B)False  True

Question 2

Which of the following statements about matter-antimatter engines is not true?

Accepted Answer

A)  Matter-antimatter engines would be great in theory, but to date we have no evidence that antimatter even exists. 
B)  Matter-antimatter reactions represent the most efficient possible reactions in terms of energy release. 
C)  Spacecraft powered by matter-antimatter engines could probably reach speeds of more than half the speed of light. 
D)  One of the major challenges to developing matter-antimatter engines is finding a way to store antimatter after it is produced. 
A)  Matter-antimatter engines would be great in theory, but to date we have no evidence that antimatter even exists. 
B)  Matter-antimatter reactions represent the most efficient possible reactions in terms of energy release. 
C)  Spacecraft powered by matter-antimatter engines could probably reach speeds of more than half the speed of light. 
D)  One of the major challenges to developing matter-antimatter engines is finding a way to store antimatter after it is produced. A

Question 3

Why is Europa considered a good candidate for the possible existence of life?

Accepted Answer

A)  Strong evidence suggests that it has a deep, subsurface ocean of liquid water. 
B)  The Galileo spacecraft found strange seasonal changes on its surface that look like they could be due to life. 
C)  It is located within our Sun's habitable zone. 
D)  It has a thick atmosphere with a surface pressure greater than that on Earth. 
A)  Strong evidence suggests that it has a deep, subsurface ocean of liquid water. 
B)  The Galileo spacecraft found strange seasonal changes on its surface that look like they could be due to life. 
C)  It is located within our Sun's habitable zone. 
D)  It has a thick atmosphere with a surface pressure greater than that on Earth. A

Question 4

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

Accepted Answer

A)  Any interstellar journey will take much longer than the lives of the crew members. 
B)  Time dilation will slow the heartbeats of the crew to a dangerously low rate. 
C)  Atoms and ions in interstellar space will hit the spacecraft like a flood of dangerous cosmic rays. 
D)  Asteroid fields floating in interstellar space will present a severe navigational challenge. 
E)  Supernova explosions could destroy spaceships passing nearby. 
A)  Any interstellar journey will take much longer than the lives of the crew members. 
B)  Time dilation will slow the heartbeats of the crew to a dangerously low rate. 
C)  Atoms and ions in interstellar space will hit the spacecraft like a flood of dangerous cosmic rays. 
D)  Asteroid fields floating in interstellar space will present a severe navigational challenge. 
E)  Supernova explosions could destroy spaceships passing nearby.

Question 5

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 6

Generalizing from a Single Example: Many would argue that our concept of life and intelligence is severely limited by the fact that we have only the "single example" of the Earth. Do you agree with this view (address the questions of life and intelligence separately)? To what extent do you feel that the search for extraterrestrial life is biased by the example of life on the Earth? Does the search for extraterrestrial intelligent life suffer more or less from the same bias?

Accepted Answer

I agree that our concept of life and int

Question 7

Although antimatter is an interesting theoretical idea, there is no evidence that it actually exists.

Accepted Answer

A) True 
 B)False

Question 8

Relativistic time-dilation means that astronauts aboard a spaceship traveling close to the speed of light will actually age less than their families left behind on the Earth.

Accepted Answer

A) True 
 B)False

Question 9

When we analyze whether a world is a possible home to life, the key thing we look for is ________.

Accepted Answer

A)  the past or present existence of liquid water 
B)  evidence of atmospheric oxygen 
C)  the presence of organic molecules such as amino acids 
D)  surface coloration changes that could indicate vegetative growth 
A)  the past or present existence of liquid water 
B)  evidence of atmospheric oxygen 
C)  the presence of organic molecules such as amino acids 
D)  surface coloration changes that could indicate vegetative growth

Question 10

According to current science, why didn't oxygen begin to accumulate in the atmosphere for more than a billion years after life appeared on the Earth?

Accepted Answer

A)  Oxygen was removed from the atmosphere by chemical reactions with surface rocks as quickly as it was released by life. 
B)  Early forms of animal life consumed the oxygen released by plants during the first billion years of life on Earth. 
C)  Early life did not release oxygen, and oxygen releasing organisms didn't evolve for a billion years after the earliest life. 
D)  Oxygen was removed from the atmosphere by dissolving in the ocean as quickly as it was released by life. 
A)  Oxygen was removed from the atmosphere by chemical reactions with surface rocks as quickly as it was released by life. 
B)  Early forms of animal life consumed the oxygen released by plants during the first billion years of life on Earth. 
C)  Early life did not release oxygen, and oxygen releasing organisms didn't evolve for a billion years after the earliest life. 
D)  Oxygen was removed from the atmosphere by dissolving in the ocean as quickly as it was released by life.

Question 11

Briefly explain the purpose of the equation
Number of Civilizations = Np × $ f_{\mathrm{}} $life × $ f_{\mathrm{}} $civilization × $ f_{\mathrm{}} $ now.

Accepted Answer

This equation is used to estim

Question 12

Which of the following best describes how the Drake equation is useful?

Accepted Answer

A)  It helps us understand what we need to know in order to determine the likelihood of finding other civilizations. 
B)  It has allowed us to determine the number of civilizations in the Milky Way Galaxy. 
C)  It allows us to calculate the masses of planets orbiting other stars. 
D)  It tells us what wavelengths of light will be most useful to examine in the search for extraterrestrial intelligence. 
A)  It helps us understand what we need to know in order to determine the likelihood of finding other civilizations. 
B)  It has allowed us to determine the number of civilizations in the Milky Way Galaxy. 
C)  It allows us to calculate the masses of planets orbiting other stars. 
D)  It tells us what wavelengths of light will be most useful to examine in the search for extraterrestrial intelligence.

Question 13

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

Accepted Answer

A)  A planet or moon that could support life, if any life happened to be on it 
B)  A planet or moon with life 
C)  A planet or moon that lies within its star's habitable zone 
D)  A planet or moon on which humans could survive if we happened to go there 
A)  A planet or moon that could support life, if any life happened to be on it 
B)  A planet or moon with life 
C)  A planet or moon that lies within its star's habitable zone 
D)  A planet or moon on which humans could survive if we happened to go there

Question 14

At about what fraction of the speed of light do today's spacecraft travel?

Accepted Answer

A)  1/2 
B)  1/10 
C)  1/100 
D)  1/1,000 
E)  1/10,000 
A)  1/2 
B)  1/10 
C)  1/100 
D)  1/1,000 
E)  1/10,000

Question 15

According to fossil evidence, how far back in time did life on Earth exist?

Accepted Answer

A)  About 3.5 billion years or more 
B)  About 2.0 billion years 
C)  About 545 million years 
D)  About 65 million years 
A)  About 3.5 billion years or more 
B)  About 2.0 billion years 
C)  About 545 million years 
D)  About 65 million years

Question 16

Which of the following is not key evidence in support of the idea that all life today shares a common ancestor?

Accepted Answer

A)  We have identified fossils of the first life forms that ever existed on Earth. 
B)  All life uses DNA and the same genetic code. 
C)  Mapping of gene sequences shows how life is all related. 
D)  All life builds proteins from the same amino acids and uses ATP to store energy in cells. 
A)  We have identified fossils of the first life forms that ever existed on Earth. 
B)  All life uses DNA and the same genetic code. 
C)  Mapping of gene sequences shows how life is all related. 
D)  All life builds proteins from the same amino acids and uses ATP to store energy in cells.

Question 17

What is the evidence that suggests planetary systems are common in the universe?

Accepted Answer

We know that stars form surrounded by di

Question 18

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 19

Which of the following was the most important for maintaining the Earth's stable climate over the time it took for large organisms to evolve?

Accepted Answer

A)  sustained volcanic activity 
B)  the cessation of the heavy bombardment phase 
C)  plate tectonics 
D)  the Moon 
E)  underground sea vents 
A)  sustained volcanic activity 
B)  the cessation of the heavy bombardment phase 
C)  plate tectonics 
D)  the Moon 
E)  underground sea vents

Question 20

Which of the following statements about matter-antimatter engines is not true?

Accepted Answer

A)  Matter-antimatter reactions represent the most efficient reactions possible in terms of energy release. 
B)  Matter-antimatter engines would be possible in theory, but to date, we have no evidence that antimatter exists. 
C)  One of the major challenges to developing matter-antimatter engines is finding a way to produce enough antimatter. 
D)  One of the major challenges to developing matter-antimatter engines is finding a way to store antimatter after it is produced. 
E)  Spacecraft powered by matter-antimatter engines could probably reach speeds of 90 percent of the speed of light. 
A)  Matter-antimatter reactions represent the most efficient reactions possible in terms of energy release. 
B)  Matter-antimatter engines would be possible in theory, but to date, we have no evidence that antimatter exists. 
C)  One of the major challenges to developing matter-antimatter engines is finding a way to produce enough antimatter. 
D)  One of the major challenges to developing matter-antimatter engines is finding a way to store antimatter after it is produced. 
E)  Spacecraft powered by matter-antimatter engines could probably reach speeds of 90 percent of the speed of light.

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

Which of the following statements about matter-antimatter engines is not true?

Why is Europa considered a good candidate for the possible existence of life?

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

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

Although antimatter is an interesting theoretical idea, there is no evidence that it actually exists.

Relativistic time-dilation means that astronauts aboard a spaceship traveling close to the speed of light will actually age less than their families left behind on the Earth.

When we analyze whether a world is a possible home to life, the key thing we look for is ________.

According to current science, why didn't oxygen begin to accumulate in the atmosphere for more than a billion years after life appeared on the Earth?

Briefly explain the purpose of the equation Number of Civilizations = Np × $f_{\mathrm{}}$ life × $f_{\mathrm{}}$ civilization × $f_{\mathrm{}}$ now.

Which of the following best describes how the Drake equation is useful?

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

At about what fraction of the speed of light do today's spacecraft travel?

According to fossil evidence, how far back in time did life on Earth exist?

Which of the following is not key evidence in support of the idea that all life today shares a common ancestor?

What is the evidence that suggests planetary systems are common in the universe?

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

Which of the following was the most important for maintaining the Earth's stable climate over the time it took for large organisms to evolve?

Which of the following statements about matter-antimatter engines is not true?

Our Place in the Universe

Discovering the Universe for Yourself

The Science of Astronomy

Making Sense of the Universe: Understanding Motion, Energy, and Gravity

Light: the Cosmic Messenger

Formation of Planetary Systems: Our Solar System and Beyond

Earth and the Terrestrial Worlds

Jovian Planet Systems

Asteroids, Comets, and Dwarf Planets: Their Nature, Orbits, and Impacts

Our Star

Surveying the Stars

Star Stuff

Bizarre Stellar Graveyard

Our Galaxy

Galaxies and the Foundation of Modern Cosmology

Dark Matter, Dark Energy, and the Fate of the Universe

The Beginning of Time

Filters

Exam 18: Life in the Universe

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

Which of the following statements about matter-antimatter engines is not true?

Why is Europa considered a good candidate for the possible existence of life?

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

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

Although antimatter is an interesting theoretical idea, there is no evidence that it actually exists.

Relativistic time-dilation means that astronauts aboard a spaceship traveling close to the speed of light will actually age less than their families left behind on the Earth.

When we analyze whether a world is a possible home to life, the key thing we look for is ________.

According to current science, why didn't oxygen begin to accumulate in the atmosphere for more than a billion years after life appeared on the Earth?

Briefly explain the purpose of the equation Number of Civilizations = Np × f f_{\mathrm{}} f​ life × f f_{\mathrm{}} f​ civilization × f f_{\mathrm{}} f​ now.

Which of the following best describes how the Drake equation is useful?

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

At about what fraction of the speed of light do today's spacecraft travel?

According to fossil evidence, how far back in time did life on Earth exist?

Which of the following is not key evidence in support of the idea that all life today shares a common ancestor?

What is the evidence that suggests planetary systems are common in the universe?

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

Which of the following was the most important for maintaining the Earth's stable climate over the time it took for large organisms to evolve?

Which of the following statements about matter-antimatter engines is not true?

Our Place in the Universe

Discovering the Universe for Yourself

The Science of Astronomy

Making Sense of the Universe: Understanding Motion, Energy, and Gravity

Light: the Cosmic Messenger

Formation of Planetary Systems: Our Solar System and Beyond

Earth and the Terrestrial Worlds

Jovian Planet Systems

Asteroids, Comets, and Dwarf Planets: Their Nature, Orbits, and Impacts

Our Star

Surveying the Stars

Star Stuff

Bizarre Stellar Graveyard

Our Galaxy

Galaxies and the Foundation of Modern Cosmology

Dark Matter, Dark Energy, and the Fate of the Universe

The Beginning of Time

Filters

Briefly explain the purpose of the equation Number of Civilizations = Np × $f_{\mathrm{}}$ life × $f_{\mathrm{}}$ civilization × $f_{\mathrm{}}$ now.