Ch 5 Earth Moon

After the Lunar Reconnaissance Orbiter (LRO) crashed into the moon, its sister spacecraft LCROSS detected an amount of water in the ejecta A) less than is contained in desert sand on Earth. B) comparable to fertile soil on Earth. C) comparable to soggy ground on Earth. D) Actually, no water was detected at all. E) comparable to dried-up lake beds on Earth.

...

The Moon lacks an atmosphere because its surface gravity is only ________ the Earth's.

1/6

The oldest rocks found on the Earth's surface date back about ________ billion years.

4

The bulk density of the Moon is ________ than that of the Earth it orbits.

60%

Earth's magnetic field A) prevents charged particles in the solar wind from reaching the surface. B) is the force behind plate tectonics. C) lines intersect the atmosphere at the equator. D) is a remnant of the solar nebula's magnetic field. E) is weakening the Van Allen radiation belts.

A

Seismic waves are most useful for mapping A) the Earth's core and mantle B) the surface of Mars with Global Surveyor C) the depths of the oceans. D) the surface of Venus with Magellan. E) the density of the hydrosphere.

A

The rate of cratering in the lunar highlands shows us that A) they range from 4.6 - 4.4 billion years old, on average. B) the oldest rocks are at least as old as the mare, but some craters are much younger. C) most of the asteroids must have hit the Moon, not the Earth. D) the largest impacts are the youngest, such as Copernicus and Tycho. E) they must be younger than the older, darker mare.

A

Which of the following layers of the Earth is unique among the terrestrial planets? A) hydrosphere B) mantle C) ionosphere D) core E) crust

A

Which of these is not a result of plate tectonics? A) the Grand Canyon B) the Mid-Atlantic Rift C) the Philippine Trench D) the San Andreas Fault E) the Andes

A

Which of these theories seems to best explain the Moon's origin? A) Impact Theory B) Fission Theory C) Fusion Theory D) Coformation Theory E) Capture Theory

A

At what phase are the tides least noticeable? A) full moon B) third quarter C) waxing crescent D) waning gibbous E) new moon

B

The critical part of the atmosphere for protecting life on the ground from excessive ultraviolet radiation is the A) troposphere. B) ozone layer. C) hydrosphere. D) ionosphere. E) stratosphere.

B

The lunar mare are found A) uniformly all over the Moon. B) mainly on the near side. C) mainly on the far side. D) only as layered rocks, since the original water was lost long ago. E) only in the dark areas of the lunar poles, where water is not boiled away.

B

The major presence of water detected on the Moon is in A) the puffs of steam seen coming from some still active lunar volcanoes. B) the floors of deep craters in the polar regions, as ice deposits that never thaw. C) the mare. D) the flows of mud seen on the walls of some craters. E) faint clouds of ice in the thin lunar atmosphere.

B

The presence of a magnetic field is a good indication that A) the Earth's interior is similar to Mercury's, as both have fields. B) the Earth has a liquid metal outer core, spinning rapidly as it rotates. C) the Earth's interior must be completely molten to the center. D) a huge iron meteorite lies somewhere high up in the mantle, not in the core. E) the Earth's interior has had time to solidify, with a rigid bar magnet created.

B

What is true of spring tides? A) The third quarter moon would be high overhead at dawn. B) The difference between low and high tides would be greatest. C) There would be one high and one low tide each day. D) The difference between low and high tides would be smallest. E) The Moon's phase will be first quarter.

B

The atmospheric gases primarily responsible for our A) argon and water vapor. B) hydrogen and helium. C) carbon monoxide and methane. D) oxygen and carbon dioxide. E) water vapor and carbon dioxide.

C

The region in which charged particles are trapped by our magnetic fields is the A) ionosphere. B) exosphere. C) Van Allen radiation belt. D) ozone layers. E) Aurora.

C

What is true of the lunar highlands? A) They are found on the Moon's northern hemisphere. B) They are less heavily cratered than the mare. C) They are the oldest part of the lunar surface. D) They are the darker regions of the Moon seen with the naked eye. E) They are younger than the darker mare.

C

Which of these age ranges best describes the lunar maria? A) 2.5 - 1.0 billion years B) a few million years to present lava flows seen erupting C) 3.9 - 3.2 billion years D) 8.6 - 6.0 billion years E) 100 - 65 million years

C

Almost all of our atmospheric gases lie in the A) mesosphere. B) ionosphere. C) stratosphere. D) troposphere. E) ozone layer.

D

At what phase would you expect to find extremely high and low tides? A) Moon phases do not impact the tides. B) new moon C) full moon D) both new and full moons E) first and third quarter

D

The Moon's near side always faces Earth due to A) conservation of angular momentum in the solar nebula. B) the solar wind. C) Earth's magnetic field. D) Earth's tidal force. E) the Sun's gravity.

D

Today, an average lunar moonquake releases about as much energy as A) the Mount St. Helens eruption. B) an atomic bomb. C) the most powerful earthquake ever recorded. D) a firecracker. E) a major U.S. city uses in 1 year.

D

What is the average molecular speed of hydrogen (mass = 1) on Earth (temperature = 300 K)? A) 2.72 m/s B) 4.71 km/s C) 4.71 m/s D) 2.72 km/s E) None of the above

D

What is true of the Moon's orbital and rotational periods? A) The orbital period is longer. B) The orbital period is greatest at full moon. C) The rotational period is longer. D) They are equal. E) The rotational period varies with the Moon's phase.

D

When strong solar winds are displaced poleward by our magnetic fields, we get A) the Van Allen radiation belts. B) hurricanes in the tropics. C) sunspots. D) intense auroral displays. E) droughts and dust bowls in the American West.

D

Which statement about our core is FALSE? A) Its magnetic field generates the protective Van Allen radiation Belts. B) The seismic data indicates the outer portion is liquid, the inner part solid. C) It is almost as hot as the Sun's glowing surface, the photosphere. D) It generates a stable and permanent magnetic field much as a regular bar magnet. E) It must be rich in both iron and nickel.

D

In noting that the Earth is "differentiated," we mean that A) the Earth is very different than any other planet we study. B) the density of oceanic basalt is less than that of granite on the mountain tops. C) the Earth's magnetic field varies at different locations on the globe. D) the radioactive heating in the core is increasing with time. E) the density increases as you descend downward toward the core.

E

The average rate of erosion on the Moon is far less than on Earth because A) the crust of the Moon is much denser than the Earth's crust. B) the Moon is much younger than the Earth. C) the Moon's magnetic field protects it from the solar wind better than ours does. D) the Moon's mare long ago dried up, so there is no more wave erosion there. E) the Moon lacks wind, water, and an atmosphere.

E

The far side of the Moon was first mapped A) by Galileo in 1610 with his first telescope. B) by NASA with its Lunar Orbiters in the 1960s. C) by William Herschel with his large reflectors in the early 1800s. D) by the Apollo astronauts on the first orbit of the Moon with Apollo 8. E) by early Russian spacecraft.

E

The smallest high tides occur when the Moon phase is A) waxing or waning gibbous. B) full. C) waxing or waning crescent. D) new. E) first or third quarter.

E

We determine the structure of the Earth's core using A) radar and sonar. B) magnetic resonance imaging. C) deep mine shafts. D) satellite imaging. E) seismic wave data.

E

Which statement about seismic waves is true? A) S waves can travel though the outer core, but P waves cannot. B) Only S waves can travel through liquid. C) In the shadow zones, neither type is observed. D) On the far side of the Earth, only the S waves on the surface can be detected. E) P waves travel faster, and thus arrive sooner than do the S waves.

E

Due to its larger mass, the Sun's gravitational effect on Earth's tides is greater than the Moon's.

False

Most lunar craters are volcanic in origin.

False

On average, the Moon orbits Earth from a distance of about 30 Earth radii.

False

Samples of the Earth's molten outer core come directly through the mantle, pour out of volcanoes, and can be studied in labs.

False

Seismic S-waves can travel through Earth's liquid outer core.

False

Spring tides occur only at new Moon, when the Moon and Sun pull together.

False

The Earth and Moon always keep the same side towards each other.

False

The Moon keeps one side facing the Earth because it doesn't rotate on its axis.

False

The Moon's surface gravity is only half the Earth's.

False

The continuing rise of carbon dioxide concentration in our troposphere is leading to worldwide cooling as dry ice forms at the poles.

False

The lunar mare are younger than any of the craters that sit in them.

False

The lunar mare radioactively date back to 4.6 billion years, at the origin of the Moon, hence their dark color due to this aging.

False

Today most scientists favor the capture theory of the Moon's origin, since it would explain why the Moon still orbits in the ecliptic plane, as do other planets.

False

When plates collide, they fuse together and come to rest.

False

________ radiation is trapped close to our surface by the greenhouse effect.

Infrared

The ________ seismic waves can pass through both solid and liquid portions of the Earth's interior, and be detected on the other side of the globe.

P

________ is responsible for heating the Earth's interior today.

Radioactive decay

________ waves cannot travel through the Earth's liquid outer core.

S

The Sun reinforces the Moon's tidal pull during ________ tides.

Spring

The ________ tides have a large change from high to low, near new and full moons.

Spring

The ________ has the largest gravitational pull on Earth.

Sun

A seismograph could register P but not S waves from an epicenter on the opposite side of the Earth.

True

Compared to Earth, the Moon lacks a hydrosphere, atmosphere, and a magnetosphere.

True

Early telescopic observers thought the lunar mare were seas of water; today we know they are not liquid water but molten basalt, long ago frozen out.

True

Greenhouse gases in our atmosphere trap just enough heat to keep the Earth's oceans liquid.

True

In most places on the seacoast, there are two high and two low tides a day.

True

In the past, most of the landmass on Earth was concentrated in a single, large continent.

True

Neap tides occur at first and third quarter phases of the Moon.

True

One source of the energy for volcanism and plate tectonics is radioactivity in the Earth's interior.

True

Our Earth is about four times larger than the Moon in diameter.

True

Seismic P-waves can be detected worldwide from any strong epicenter.

True

Seismic P-waves can travel through both solid and liquid materials.

True

The Earth's hotter, inner core is liquid and its cooler, outer core is solid.

True

The Earth's inner core is about the same temperature as the surface of the Sun.

True

The Moon and the crustal rocks of Earth are similar in density.

True

The Moon's lower density indicates it has a smaller concentration of iron in its core, as does the absence of a lunar magnetic field.

True

The crust on the near side of the Moon is on average thinner than the crust on the far side, due to our tidal pull on the Moon.

True

The ozone layer lies above the troposphere and below the mesosphere.

True

The three most abundant gases in our atmosphere are nitrogen, oxygen, and argon.

True

The tidal pull of the Moon is an example of a differential force, as the near and far sides of the Earth do not experience the same gravitational pull of the Moon.

True

There is no evidence for plate tectonics on the Moon today.

True

Weather occurs in the troposphere.

True

The most important greenhouse effect gas in our atmosphere is ________. 91

carbon dioxide

Because the interior of the Earth is ________, the crust is much less dense than the core.

differentiated (or molten)

The neap tide can occur at the ________ or ________ phases of the Moon.

first, third quarter

The greenhouse effect always results in a ________ surface temperature.

hotter

Our molten core is believed to consist primarily of the element ________.

iron

For differentiation to have occurred, the Earth's interior must have been ________.

molten

The ________ tides occur when there is little tidal variation, near first and third quarter moons.

neap

The spring tide can occur at either ________ or ________ phases of the Moon.

new, full

The most abundant gas in the Earth's atmosphere is ________.

nitrogen

The ________ in our atmosphere is the result of photosynthesis by plants.

oxygen

The oxygen in our atmosphere is produced by ________.

photosynthesis by plants

The water that has been detected on the Moon lies at its ________.

poles

The tidal pull of the Sun largely cancels that of the Moon at the ________ phases.

quarter

To map the Earth's interior, we rely on ________ waves created by earthquakes.

seismic

Plate ________ is the process by which convection within the mantle reforms the crust above it.

tectonics

The difference in the Moon's gravitational force on the near and far sides of the Earth produces a ________.

tidal bulge

The Moon's spin-orbit resonance shows it is ________ with the Earth.

tidally locked

Weather always occurs in the lowest layer of the atmosphere, the ________.

troposphere

The ozone layer blocks much of the Sun's ________ radiation.

ultraviolet