Deck 7: Searching for Life in Our Solar System

Question 1

If life does indeed exist elsewhere in our solar system it will most likely take the form of

A) human beings
B) plants
C) birds
D) microbes or other simple life

Answer 1

microbes or other simple life

Question 2

All of the most likely alternatives to water as a biological solvent are liquids at

A) higher temperatures
B) lower temperatures
C) lower pressures
D) similar temperatures

Answer 2

lower temperatures

Question 3

In searching for life in the solar system, which basic requirement of life is the most fundamental and the one we always look for?

A) the presence of organic matter
B) the presence of an energy source
C) the presence of a liquid medium, most likely water
D) the presence of oxygen

Answer 3

the presence of a liquid medium, most likely water

Question 4

Given that organic molecules need to react in order to produce life, this suggests we should search for worlds in the solar system that have

A) either an atmosphere, or a surface or subsurface liquid medium such as water, or both.
B) organic molecules on their surfaces
C) an atmosphere
D) rocky surfaces

Question 5

A newly discovered asteroid of the Aten family is found to be 50% closer to the Sun than the Earth is. Given this, how much sunlight does it receive compared to the Earth?

A) half as much
B) four times as much
C) twice as much
D) about the same

Question 6

What happens to the rate of most chemical reactions as the temperature decreases?

A) the rate of reaction drops rapidly
B) the rate of reaction drops only slightly
C) the rate of reaction increases rapidly
D) the rate of reaction stays the same

Question 7

Photosynthetic life existing on a planet farther from the Sun than the Earth would most likely be

A) smaller, less efficient at collecting solar radiation or have a faster metabolism than photosynthetic life on Earth
B) identical to photosynthetic life on Earth
C) larger, more efficient at collecting solar radiation or have a slower metabolism than photosynthetic life on Earth
D) impossible

Question 8

The necessary chemical elements of life should

A) only be found on the Earth and Mars
B) be widespread in the solar system but not elsewhere in our Milky Way galaxy
C) be widespread throughout the universe
D) be widespread in our Milky Way galaxy but not in other galaxies

Question 9

Molecules like water in which electrons are distributed unevenly within the molecule are referred to as

A) bipolar
B) ionic
C) charged
D) polar

Question 10

Which one of the following properties is unique to water?

A) it has a high heat capacity
B) it is a good solvent
C) it is a liquid over a wide temperature range
D) it expands on freezing

Question 11

Which of the following is NOT a basic requirement for chemically based life?

A) a liquid medium to transport biological molecules
B) a source of molecules from which to build living cells
C) oxygen from photosynthesis
D) a source of energy to fuel metabolism

Question 12

The planet Saturn is approximately 10 times farther away from the Sun than the Earth is. Given this, how much sunlight does it receive compared to the Earth?

A) 1/1,000th
B) 1/10,000th
C) 1/100th
D) 1/10ᵗʰ

Question 13

Habitability generally refers to an environment capable of sustaining

A) human life
B) plant life
C) microbial life only
D) any kind of life

Question 14

The strong forces of attraction that exist between water molecules and are responsible for many of its unique properties as a solvent are called

A) dispersion forces
B) ionic bonds
C) hydrogen bonds
D) covalent bonds

Question 15

Which of the following alternatives to water has a wider temperature range over which it is a liquid?

A) ammonia
B) methanol
C) methane
D) ethane

Question 16

If ice were denser than water, during winter lakes and ponds would

A) completely freeze
B) remain liquid
C) freeze on the surface but remain liquid beneath
D) freeze on the bottom but remain liquid at the surface

Question 17

Which of the following is an advantage that liquid water has as a biological solvent compared to other alternatives?

A) when it freezes it becomes less dense
B) it is a liquid over a wide temperature range and remains liquid at higher temperatures
C) it is able to dissolve many things
D) all of these are advantages

Question 18

The search for life in the solar system that is similar to life on Earth is essentially a search for

A) organic molecules
B) liquid water
C) molecular oxygen
D) energy sources

Question 19

Even though ethane (C₂H₆) has a liquid temperature range almost as wide as water, it is not as good a biological solvent as water because it is a liquid at

A) much higher temperatures which would result in the breakdown of fragile biological molecules
B) very high pressures that are unlikely to be found elsewhere
C) very low pressures that are unlikely to be found elsewhere
D) much lower temperatures which would result in extremely slow metabolic reactions

Question 20

If we place living cells in a nonpolar solvent like methane or ethane,

A) their membranes will thicken, preventing molecular transport across the membrane
B) they will rapidly explode due to pressure caused by the solvent building up inside the cell
C) their membranes will most likely dissolve as cell membranes are also nonpolar
D) they will function in much the same way as they do in water

Question 21

Although very unlikely, if life exists on Venus today, it will most likely be found

A) at the center of the planet
B) just beneath the surface
C) on the surface
D) floating high in the atmosphere

Question 22

Most of the carbon dioxide on Venus

A) has frozen out in the polar regions
B) is dissolved in oceans of liquid water, forming carbonate rocks
C) is still present in the atmosphere
D) has escaped into space

Question 23

Which of the following is not property of a dwarf planet?

A) symmetrical shape
B) orbits the Sun
C) intermediate in size between an asteroid and a small terrestrial planet
D) irregular shape

Question 24

If life exists on Mars today, it will most likely be found

A) on the surface
B) at the center of the planet
C) beneath the surface where liquid water may still exist
D) floating high in the atmosphere

Question 25

Some Jovian moons may have liquid water

A) beneath their surfaces
B) at their centers
C) on their surfaces
D) in their atmospheres

Question 26

Mars may have been more Earth-like in the past because

A) its atmosphere was thicker and warmer
B) it was rotating more rapidly
C) the Sun was dimmer, putting out less solar radiation
D) it was not as close to the Sun

Question 27

Venus may have been more Earth-like in the past because

A) it was rotating more rapidly
B) the Sun was dimmer, putting out less solar radiation
C) it was not as close to the Sun
D) its atmosphere was thinner

Question 28

What would probably be the most likely source of energy for life in Jovian atmospheres?

A) sunlight
B) chemical reactions powered by lightning
C) meteoroid impacts
D) solar wind particles from the Sun

Question 29

Most of the carbon dioxide on the Earth

A) is dissolved in the oceans, forming carbonate rocks
B) has frozen out in the polar regions
C) has escaped into space
D) is still present in the atmosphere

Question 30

Europa may have a subsurface ocean of liquid water due to

A) the insulating properties of its icy surface
B) tidal heating from Jupiter and the other Galilean moons
C) internal heat left over from its formation
D) tidal heating from the Sun

Question 31

Mercury and the Moon do not have atmospheres because

A) their surfaces are so cold that any atmospheric gases freeze out onto their surfaces
B) charged particles from the Sun have stripped away their atmospheres
C) they are rotating too rapidly, causing their atmospheres to be thrown out into space
D) their gravities are too weak to prevent atmospheric gases escaping into space

Question 32

How does the surface temperature and atmospheric pressure on Venus compare with the Earth?

A) higher temperatures and pressures
B) lower temperatures but higher pressures
C) lower temperatures and pressures
D) higher temperatures but lower pressures

Question 33

The surface of Venus is much hotter than the Earth because it

A) has no magnetic field
B) has a very thick atmosphere of carbon dioxide
C) has a much higher rate of volcanic activity
D) is closer to the Sun

Question 34

Water is present on the Moon and Mercury in the form of

A) liquid water present just beneath the surface
B) ice in polar craters
C) vapor in the atmosphere
D) oceans of liquid water on the surface

Question 35

The planet Venus is often referred to as the Earth's "sister planet" because

A) it is almost the same size and density
B) it looks like the Earth through a telescope
C) its atmosphere has the same composition
D) its surface is very similar

Question 36

Mercury and the Moon are probably the least-habitable bodies in the solar system because they

A) are unlikely to have liquids anywhere
B) have never had carbon compounds on their surfaces
C) do not have atmospheres containing oxygen
D) do not receive any sunlight

Question 37

Based on its distance from the Sun, we would expect the surface of Venus to be

A) much hotter than the Earth
B) much colder than the Earth
C) a little hotter than the Earth
D) the same temperature as the Earth

Question 38

In order for life to survive in the atmospheres of Jupiter and Saturn it would have to

A) be high in the atmosphere where it could collect solar radiation
B) be at the center, close to the rocky core where a rocky surface exists
C) be large and buoyant, allowing it to maintain a stable altitude in the atmosphere
D) float on the surface of the layer of liquid metallic hydrogen

Question 39

The biggest obstacle to life being present in the atmospheres of Jupiter and Saturn is the

A) absence of liquid water in their atmospheres
B) high levels of solar radiation that would destroy any biological molecules
C) strong vertical wind speeds that would rapidly carry organisms into the hot interior where they would be destroyed
D) very low temperatures at the tops of the clouds where water would not be liquid

Question 40

If life exists in Uranus and Neptune, it will most likely be found

A) in the oceans of liquid ices beneath the surface
B) floating on the surface of a layer of liquid metallic hydrogen
C) high in the atmosphere where it could collect solar radiation
D) at the center, close to the rocky core where a rocky surface exists

Question 41

Which dwarf planet did the NASA Dawn spacecraft enter into orbit around in 2015?

A) Pluto
B) Eris
C) Ceres
D) Haumea

Question 42

Which kind of robotic space mission enables us to take a quick look at a planet?

A) sample return
B) flyby
C) orbiter
D) lander/probe

Question 43

The Curiosity rover is an example of which kind of robotic spacecraft?

A) flybys
B) sample return
C) landers
D) orbiters

Question 44

Most of the detailed information about the planets in our solar system comes from

A) telescopic observations from Earth
B) robotic spacecraft
C) human visits
D) meteorites

Question 45

An extrasolar planet in the HD 4308 system orbits its parent star at a distance of 17.1 million kilometers and takes 15.56 Earth days to complete one orbit. Given this and assuming that planet has a very low mass compared to the parent star, what is the mass of the parent star?

A) 3.25 10³⁰ kg
B) 2.00 10³⁰ kg
C) 1.25 10³⁰ kg
D) 1.64 10³⁰ kg

Question 46

Which kind of robotic space mission enables us to determine the chemical composition of a solar system body in a laboratory?

A) sample return
B) flyby
C) lander/probe
D) orbiter

Question 47

Stardust was an example of which kind of mission?

A) lander
B) flyby
C) sample return
D) orbiter

Question 48

Which kind of robotic space mission enables us to determine the chemical composition of a planet's surface and atmosphere remotely?

A) sample return
B) lander/probe
C) orbiter
D) flyby

Question 49

Which kind of robotic space mission enables us to study a planet for an extended period of time?

A) lander/probe
B) sample return
C) flyby
D) orbiter

Question 50

Dwarf planets are very similar to

A) larger Jovian moons
B) the Earth's moon
C) smaller Jovian moons
D) comets

Question 51

Which spacecraft dropped a problem into the atmosphere of Jupiter in 1995?

A) Galileo
B) Cassini
C) Voyager 2
D) Pioneer 10

Question 52

Hayabusa was an example of which kind of mission?

A) lander
B) flyby
C) sample return
D) orbiter

Question 53

Voyagers 1 and 2 were examples of which kind of space mission?

A) flyby
B) orbiter
C) sample return
D) lander/probe

Question 54

A common way a robotic spacecraft can be accelerated and have its trajectory changed without the use of any fuel is via

A) a gravitational slingshot from another spacecraft
B) radiation pressure from the Sun
C) the ejection of mass from the probe
D) a gravitational slingshot from another planet

Question 55

Small bodies like asteroids and comets are unlikely to harbor life because they

A) are constantly colliding with each other, sterilizing any life that may be present
B) have not had liquid water inside them for extended periods now or in the past
C) do not contain any organic molecules
D) are so far from the Sun that any water would be permanently frozen

Question 56

Which dwarf planet did the NASA New Horizons spacecraft flyby in 2015?

A) Pluto
B) Eris
C) Ceres
D) Haumea

Question 57

The Huygens probe is an example of which kind of robotic spacecraft?

A) orbiter
B) sample return
C) lander
D) flyby

Question 58

The Mars Curiosity rover, landed on the surface of Mars using

A) balloons
B) a skycrane
C) parachutes
D) airbags

Question 59

The Rosetta mission to the comet 67P/Churyumov-Gerasimenko is an example of which kind of robotic space mission?

A) lander/probe
B) flyby
C) sample return
D) orbiter

Question 60

Which of the following planets has not yet been studied with an orbiter?

A) Saturn
B) Mars
C) Uranus
D) Venus