AST 111 Study Questions (Latest Update) with
Verified Answers
Which planet by itself contains the majority of mass of all the planets? a. Jupiter
b. Saturn c. Earth d. Venus e. Uranus - ✔✔A
Our understanding of the solar system has come in a way that can best be described as:
a. constant since prehistoric times.
b. slow and steady since the discovery of the telescope by Galileo.
c. erratic, with spurts when new planets were found.
d. steady until the last decade, when the decline in the space program slowed it a great deal.
e. explosive, with us learning more in the past few decades than in all previous history. -
✔✔E
What is the goal of comparative planetology?
a. to use planetary positions to foretell the future
b. to find which planets will be most suitable for future colonization
c. to help plan future visits by unmanned probes, orbiters, and rovers
d. to determine the origin and evolution of the solar system
e. to find out how our own solar system compares with extrasolar ones - ✔✔D
What is true about solar system densities?
a. The denser planets lie closer to the Sun.
b. In differentiated bodies, the denser materials lie near their surfaces.
c. The asteroids all have about the same density.
d. Saturn has the same density as water.
,e. Planetary density increases with increasing distance from the Sun. - ✔✔A
The planet's orbital period is:
a. the time it takes it to rotate and have the same face toward us again.
b. the time it takes to return to the same location in the sky, relative to the Sun.
c. the time it takes for a satellite to orbit it.
d. the time it takes for it to retrograde back to the same position as we pass it.
e. the time its magnetic field takes to spin once. - ✔✔B
Masses of the planets are easiest to determine if:
a. they are terrestrial and the extra size of the planet's disk can be measured.
b. they are jovian and their oblateness can be found.
c. they have natural satellites whose motions can be precisely measured.
d. they are dense and easily deflect the path of passing spacecraft.
e. they move rapidly and their periods are easily measured. - ✔✔C
The average density of each planet in the solar system is determined by taking its mass and
dividing that by its:
a. radius.
b. diameter.
c. surface area.
d. radius squared.
e. volume. - ✔✔E
Which of these bodies has the lowest density?
a. Saturn
b. Jupiter
,c. a comet
d. an asteroid
e. a Kuiper Belt object - ✔✔C
The rotation periods of Venus, Jupiter, Saturn, Uranus and Neptune are difficult to determine
because:
a. they rotate so fast.
b. they are all gas giants.
c. they are so far away from the Sun.
d. their surface features are obscured by their atmospheres.
e. each one has a large satellite that interferes with this measurement. - ✔✔D
In the planet must have:
a. rings.
b. moons.
c. a solid surface.
d. a known size and distance from Earth.
e. planets further from the Sun than itself.
order to determine the mass of a planet by applying Newton's laws of motion and gravity, -
✔✔B
The plane in which almost all planets orbit the Sun is called the: a. equator of the solar system.
b. ecliptic.
c. equant.
d. node.
e. galactic plane. - ✔✔B
Which statement about the motion of the planets is incorrect?
, a. Most orbit above the Sun's equator.
b. All revolutions of major planets are counterclockwise.
c. The orbits of most planets are almost circular, with low eccentricities. d. Most planets move
in the Earth's equatorial plane.
e. Most planets rotate in the counterclockwise direction when viewed from the North. -
✔✔D
Astronomers have not yet been able to detect planets outside our solar systems. - ✔✔False
The solar system contains the sun, eight major bodies called planets, and at least thousands
smaller bodies. - ✔✔True
Our solar system contains more than 100 Kuiper Belt objects larger than 300 km in diameter. -
✔✔True
Our Solar System contains 65 moons (as of Summer 2007) - ✔✔False
A planet's sidereal orbital period can be measured from repeated observations of its location in
the sky (so long as Earth's own motion around the Sun is properly taken into account). -
✔✔True
Earth is nearly twice as large as Venus - ✔✔False
The Masses of all the planets combines is about 1% of that of the Sun. - ✔✔True
All the Jovian planets lie beyond the asteroid belt. - ✔✔True
Of all the terrestrial planets, Mercury's orbit is most eccentric and tilted most above the
ecliptic. - ✔✔True
Verified Answers
Which planet by itself contains the majority of mass of all the planets? a. Jupiter
b. Saturn c. Earth d. Venus e. Uranus - ✔✔A
Our understanding of the solar system has come in a way that can best be described as:
a. constant since prehistoric times.
b. slow and steady since the discovery of the telescope by Galileo.
c. erratic, with spurts when new planets were found.
d. steady until the last decade, when the decline in the space program slowed it a great deal.
e. explosive, with us learning more in the past few decades than in all previous history. -
✔✔E
What is the goal of comparative planetology?
a. to use planetary positions to foretell the future
b. to find which planets will be most suitable for future colonization
c. to help plan future visits by unmanned probes, orbiters, and rovers
d. to determine the origin and evolution of the solar system
e. to find out how our own solar system compares with extrasolar ones - ✔✔D
What is true about solar system densities?
a. The denser planets lie closer to the Sun.
b. In differentiated bodies, the denser materials lie near their surfaces.
c. The asteroids all have about the same density.
d. Saturn has the same density as water.
,e. Planetary density increases with increasing distance from the Sun. - ✔✔A
The planet's orbital period is:
a. the time it takes it to rotate and have the same face toward us again.
b. the time it takes to return to the same location in the sky, relative to the Sun.
c. the time it takes for a satellite to orbit it.
d. the time it takes for it to retrograde back to the same position as we pass it.
e. the time its magnetic field takes to spin once. - ✔✔B
Masses of the planets are easiest to determine if:
a. they are terrestrial and the extra size of the planet's disk can be measured.
b. they are jovian and their oblateness can be found.
c. they have natural satellites whose motions can be precisely measured.
d. they are dense and easily deflect the path of passing spacecraft.
e. they move rapidly and their periods are easily measured. - ✔✔C
The average density of each planet in the solar system is determined by taking its mass and
dividing that by its:
a. radius.
b. diameter.
c. surface area.
d. radius squared.
e. volume. - ✔✔E
Which of these bodies has the lowest density?
a. Saturn
b. Jupiter
,c. a comet
d. an asteroid
e. a Kuiper Belt object - ✔✔C
The rotation periods of Venus, Jupiter, Saturn, Uranus and Neptune are difficult to determine
because:
a. they rotate so fast.
b. they are all gas giants.
c. they are so far away from the Sun.
d. their surface features are obscured by their atmospheres.
e. each one has a large satellite that interferes with this measurement. - ✔✔D
In the planet must have:
a. rings.
b. moons.
c. a solid surface.
d. a known size and distance from Earth.
e. planets further from the Sun than itself.
order to determine the mass of a planet by applying Newton's laws of motion and gravity, -
✔✔B
The plane in which almost all planets orbit the Sun is called the: a. equator of the solar system.
b. ecliptic.
c. equant.
d. node.
e. galactic plane. - ✔✔B
Which statement about the motion of the planets is incorrect?
, a. Most orbit above the Sun's equator.
b. All revolutions of major planets are counterclockwise.
c. The orbits of most planets are almost circular, with low eccentricities. d. Most planets move
in the Earth's equatorial plane.
e. Most planets rotate in the counterclockwise direction when viewed from the North. -
✔✔D
Astronomers have not yet been able to detect planets outside our solar systems. - ✔✔False
The solar system contains the sun, eight major bodies called planets, and at least thousands
smaller bodies. - ✔✔True
Our solar system contains more than 100 Kuiper Belt objects larger than 300 km in diameter. -
✔✔True
Our Solar System contains 65 moons (as of Summer 2007) - ✔✔False
A planet's sidereal orbital period can be measured from repeated observations of its location in
the sky (so long as Earth's own motion around the Sun is properly taken into account). -
✔✔True
Earth is nearly twice as large as Venus - ✔✔False
The Masses of all the planets combines is about 1% of that of the Sun. - ✔✔True
All the Jovian planets lie beyond the asteroid belt. - ✔✔True
Of all the terrestrial planets, Mercury's orbit is most eccentric and tilted most above the
ecliptic. - ✔✔True
