All Test 3

What percentage of the solar nebula's mass consisted of rocky material?

0.4 percent

What percentage of the mass of the solar nebula consisted of elements other than hydrogen and helium?

2 percent

Suppose astronomers built a 60-meter telescope. How much greater would its light-collecting area be than that of the 10-meter Keck telescope?

36

How much greater is the light-collecting area of one of the 10-meter Keck telescopes than that of the 5-meter Hale telescope?

4

What do astronomers mean by light pollution?

Light pollution refers to light used for human activities that brightens the sky and hinders astronomical observations.

Determining how fast a distant galaxy is moving away from Earth.

spectroscopy

Learning the composition of a distant star.

spectroscopy

Which of the following is not an advantage of spacecraft flybys over ground-based telescope observations?

Spacecraft can monitor changes in a planet's atmosphere over long times.

Interferometry uses two or more telescopes to achieve:

an angular resolution equivalent to that of a much larger telescope.

Law of Reflection:

angle of incidence is always equal to angle of reflection

Which of the following three kinds of objects resides closer to the Sun on average?

asteroids

What are the main constituents of the jovian planets?

hydrogen and helium

What is Jupiter's main ingredient?

hydrogen and helium

The solar nebula was 98 %

hydrogen and helium.

The processes responsible for virtually all surface geology are

impact cratering, volcanisms, tectonics, and erosion

Where does nuclear fusion occur in the Sun?

in its core

Where is most of the water on Mars?

in its polar caps and subsurface ground ice

If you had only one telescope and wanted to take both visible-light and ultraviolet pictures of stars, where should you locate your telescope?

in space

If you wanted a radio telescope to achieve the same angular resolution as a visible-light telescope, it would need to be:

much larger

Refraction can cause

parallel light rays to converge to a focus.

What causes the release of oxygen into Earth's atmosphere?

photosynthesis

What process has shaped Earth's surface more than any other?

plate tectonics

In what part of the electromagnetic spectrum do the biggest telescopes on Earth operate?

radio

In what wavelength range was interferometry first routinely used?

radio

What is the longest-lasting internal heat source responsible for geological activity?

radioactive decay

Which internal energy source is the most important in continuing to heat the terrestrial planets today?

radioactivity

Which of the following best describes the lunar maria?

relatively smooth, flat plains on the Moon

Olympus Mons is a

shield volcano on Mars.

Refraction

the bending of light when it passes from one substance into another

Which of the following describes tectonics?

the disruption of a planet's surface by internal stresses

Which of the following describes impact cratering?

the excavation of bowl-shaped depressions by asteroids or comets striking a planet's surface

What is the exosphere?

the highest layer in the atmosphere

What is the troposphere?

the lowest layer in the atmosphere

Which of the following could not be measured by an observation that uses only imaging?

the rate at which a variable star brightens and dims

Which of the following could not be determined by an observation that uses only spectroscopy?

the size of a distant galaxy

Studying how a star's hot upper atmosphere changes with time.

timing

The proper order of the layers of a generic atmosphere from lowest altitude to highest is

troposphere, stratosphere, thermosphere, exosphere.

What kind of light warms the stratosphere?

ultraviolet light

Which of the following forms of light can be observed with telescopes at sea level?

visible light, radio waves

A minute of arc,or arcminute

a unit of angular measurements equal to one sixtieth (1/60) of one degree

The terrestrial planet cores contain mostly metal because

metals sank to the center during a time when the interiors were molten throughout.

The sky is blue because

molecules scatter blue light more effectively than red light.

What fraction of the moons of the planets orbit in the same direction that their planets rotate?

most

Large moons orbit their planets in the same direction the planet rotates:

most of the time.

The age of our solar system is approximately

4.6 billion years.

Which jovian planet does NOT have rings?

All the jovian planets have rings.

Suppose you view the solar system from high above Earth's North Pole. Which of the following statements about planetary orbits will be true?

All the planets orbit counterclockwise around the Sun.

A telescope's diameter tells us its light-collecting area

Area = π (diameter/2)2

Why did the solar nebula heat up as it collapsed?

As the cloud shrank, its gravitational potential energy was converted to kinetic energy and then into thermal energy.

Which is the densest planet in the solar system?

Earth

The largest terrestrial planet and jovian planet are, respectively:

Earth and Jupiter.

Which of the following best describes convection?

It is the process in which warm material expands and rises while cool material contracts and falls.

All the planets in the solar system rotate in the same direction as they orbit the Sun.

False

X-ray telescope mirrors are very similar to optical telescope mirrors.

False

What is meant by spectral resolution?

It is a measure of how close two spectral lines can be distinguished.

Why does Earth have the strongest magnetic field among the terrestrial worlds?

It is the only one that has both a partially molten metallic core and reasonably rapid rotation.

Which describes our understanding of flowing water on Mars?

It was important once, but no longer.

What is the Oort cloud?

It's not really a cloud at all, but rather refers to the trillion or so comets thought to orbit the Sun at great distances.

What's unusual about our Moon?

It's surprisingly large relative to the planet it orbits.

How did the lunar maria form?

Large impacts fractured the Moon's lithosphere, allowing lava to fill the impact basins.

What are the two most important properties of a telescope?

Light-collecting are and Angular resolution

Which of the following show evidence of ancient river beds?

Mars

Which planet, other than Earth, has visible water ice on it?

Mars

Which of the following planets has the least substantial atmosphere?

Mercury

The terrestrial planets in our solar system are:

Mercury, Venus, Earth, and Mars.

The most metal-rich terrestrial planet is

Mercury.

Rank the five terrestrial worlds in order of size from smallest to largest:

Moon, Mercury, Mars, Venus, Earth

Which of the following statements is not an observed pattern of motion in our solar system?

Most planets orbit at the same speed.

What do we conclude if a planet has few impact craters of any size?

Other geological processes have wiped out craters.

Which of the following statements best describes the two principal advantages of telescopes over eyes?

Telescopes can collect far more light with far better angular resolution.

Which of the following is not a major difference between the terrestrial and jovian planets in our solar system?

Terrestrial planets contain large quantities of ice and jovian planets do not.

Which of the following statements about our Sun is NOT true?

The Sun's diameter is about five times that of Earth.

According to our theory of solar system formation, why do all the planets orbit the Sun in the same direction and in nearly the same plane?

The laws of conservation of energy and conservation of angular momentum ensure that any rotating, collapsing cloud will end up as a spinning disk.

Under what circumstances can differentiation occur in a planet?

The planet must have a molten interior.

What is differentiation in planetary geology?

The process by which gravity separates materials according to density.

Suppose the angular separation of two stars is smaller than the angular resolution of your eyes. How will the stars appear to your eyes?

The two stars will look like a single point of light.

Which of the following observations indicates that conditions on Mars may have been suitable for life in the past?

There are dried-up riverbeds on Mars.

According to the nebular theory, what are asteroids and comets?

They are leftover planetesimals that never accreted into planets

Which of the following best describes the nature and origin of the atmospheres of the Moon and Mercury?

They have thin exospheres only, with gas coming from impacts of subatomic particles and photons.

Which of the following is not a characteristic of the outer planets?

They have very few, if any, satellites.

What do meteorites reveal about the solar system?

They reveal that the age of the solar system is approximately 4.6 billion years.

Where did the elements heavier than hydrogen and helium come from?

They were produced inside stars.

The more massive planets in the solar system tend to be less dense than the lower mass planets.

True

Venus has a thicker atmosphere than Earth.

True

Winter and summer differ in length on Mars because of its elliptical orbit.

True

X rays from astronomical objects can only be detected from telescopes in space.

True

Which of the following worlds has the most substantial atmosphere?

Venus

Which terrestrial world has the most atmosphere?

Venus

Which planet(s) have an atmosphere that consists mostly of carbon dioxide?

Venus and Mars

Which of the following correctly lists the terrestrial worlds in order from the thickest atmosphere to the thinnest atmosphere? (Note: Mercury and the Moon are considered together in this question.)

Venus, Earth, Mars, Moon/Mercury

Are there any exceptions to the rule that planets rotate with small axis tilts and in the same direction that they orbit the Sun?

Venus, Uranus, and Pluto are exceptions

The planet closest in size to Earth is

Venus.

Focal Point

When light reflects from a concave surface then after reflection it converges to a point

What do we mean when we say that the terrestrial worlds underwent differentiation?

When their interiors were molten, denser materials sank toward their centers and lighter materials rose toward their surfaces.

In general, what kind of planet would you expect to have the thickest lithosphere?

a small planet

A terrestrial world's lithosphere is ________.

a layer of relatively strong, rigid rock, encompassing the crust and part of the mantle

What is the Kuiper belt?

a region of the solar system beginning just beyond the orbit of Neptune that contains many icy comets

The Hubble Space Telescope obtains higher-resolution images than most ground-based telescopes because it is:

above Earth's atmosphere.

The three principal sources of internal heat of terrestrial planets are

accretion, differentiation, and radioactivity

Which technology can allow a single ground-based telescope to achieve images as sharp as those from the Hubble Space Telescope?

adaptive optics

How many of the planets orbit the Sun in the same direction that Earth does?

all

Why does Mars have more extreme seasons than Earth?

because it has a more eccentric orbit in addition to its tilt

Where are most of the known asteroids found?

between the orbits of Mars and Jupiter

What are the conditions necessary for a terrestrial planet to have a strong magnetic field?

both a molten metallic core and reasonably fast rotation

When we say that jovian planets contain significant amounts of hydrogen compounds, we mean all the following chemicals EXCEPT ______.

carbon dioxide

Which lists the major steps of solar system formation in the correct order?

collapse, condensation, accretion

Leftover ice-rich planetesimals are called

comets.

Which of the following did not occur during the collapse of the solar nebula?

concentrating denser materials nearer the Sun

From center to surface, which of the following correctly lists the interior layers of a terrestrial world?

core, mantle, crust

If our eyes were sensitive only to X rays, the world would appear __________.

dark because X-ray light does not reach Earth's surface

Planetary orbits are:

fairly circular and in the same plane.

Comets in the Kuiper belt and Oort cloud have long, beautiful tails that we can see when we look through telescopes.

false

Our Moon is about the same size as moons of the other terrestrial planets.

false

How much greater is the light-collecting area of a 6-meter telescope than a 3-meter telescope?

four times

Volcanism is more likely on a planet that

has high internal temperatures.

Which have more moons on average?

jovian planets

Sun appears distorted at sunset because

light bends in Earth's atmosphere.

Which of the following lists the ingredients of the solar nebula from highest to lowest percentage of mass of the nebula?

light gases (H, He), hydrogen compounds (H2O, CH4, NH3), rocks, metals

What is the name of the outer rigid layer of a planet?

lithosphere

Where is most of the CO2 that has outgassed from Earth's volcanoes?

locked up in rocks