Astronomy test 2- Terrestrial Planets – Flashcards
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Mercury has..
(A) almost no atmosphere.
(B) an atmosphere of carbon dioxide with about 90 times the surface pressure of Earth's.
(C) an atmosphere of carbon dioxide with about 1% the surface pressure of Earth's.
(D) an atmosphere whose temperature and pressure are at the triple point of water.
(E) an atmosphere whose temperature and pressure are at the triple point of methane.
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(A) almost no atmosphere.
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Which of the following planets can be said to have almost no atmosphere?
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mercury
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the presence of frozen water on Mercury is
(A) possible because the planet always keeps the same side turned away from the Sun.
(B) possible because it has no axial tilt so that its poles never face the Sun
(C) impossible because the night side, where it is cold, eventually rotates to face the Sun.
(D) impossible because every part of it is too hot for water ice.
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(B) possible because it has no axial tilt so that its poles never face the Sun
Yes. The Sun never reaches the bottoms of craters at the poles, so they are very cold.
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The temperature at the poles of Mercury is expected to be(A) Very hot during the Mercurian summer when the Sun shines to the bottoms of the craters.
(B) Very hot all of the time on mountain peaks hit by the Sun and very cold all of the time in craters never hit by the Sun.
(C) Very hot all of the time because Mercury is close to the Sun.
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(B) Very hot all of the time on mountain peaks hit by the Sun and very cold all of the time in craters never hit by the Sun.
Yes. At the poles,the Sun is always on the horizon..
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Mercury rotates so that it
(A) always keeps the same side toward the Sun so that solar time never changes.
(B) has a solar day that lasts for one complete orbit around the Sun.
(C) has a solar day that last for two complete orbits around the Sun.
(D) has a solar day that last for three complete orbits around the Sun.
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C) has a solar day that last for two complete orbits around the Sun.
Yes. Relative to the distant stars, it rotates three times for each two orbits.
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Relative to the distant stars, Mercury
(B) completes 1.5 rotations each time it orbits the Sun.
Yes. In two orbits it rotates three times: a 3:2 orbital lock.
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(B) completes 1.5 rotations each time it orbits the Sun.
Yes. In two orbits it rotates three times: a 3:2 orbital lock.
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Which of the following planets has a magnetic field whose intensity is about 1% of the intensity of the Earth's magnetic field?
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Mercury
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The current model for the way that planets acquire magnetic fields requires which of the following combinations of things?
(A) rotation and an iron core.
(B) only an iron core.
(C) rotation and a core that contains a liquid electrical conductor.
(D) only a core that contains a liquid electrical conductor.
(E) rotation and a core that contains liquid iron.
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(C) rotation and a core that contains a liquid electrical conductor.
Yes. The conductor does not need to be iron. On Jupiter, it is metallic hydrogen.
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which of the following planets has no moons at all?
(A) Mercury
(B) Earth
(C) Mars
(D) Jupiter
(E) Neptune
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mercury
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Space probes often visit several planets before getting to their final destinations. The main reason they do this is to
(A) see more planets in a single trip.
(B) reduce the amount of rocket fuel needed.
(C) arrive at the destination at the right time.
(D) take on fuel.
(E) recharge their batteries.
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(B) reduce the amount of rocket fuel needed.
Yes. They can use each planet's gravitational field to change their velocity without using fuel.
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Space probes often use gravitational slingshot maneuvers. The main purpose of these maneuvers is to
(A) change the direction and speed of the probe without using rockets.
(B) launch probes from Earth orbit without using rockets.
(C) see more planets in a single trip.
(D) arrive at the destination at the right time.
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(A) change the direction and speed of the probe without using rockets.
Yes. The main cost of the maneuver is the time it takes. Some probes take many years to work their way to their targets.
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The first space probe to reach the planet Mercury was
(A) Pioneer 10.
(B) MESSENGER.
(C) Mariner 9.
(D) Mariner 10.
(E) Pioneer 11.
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D) Mariner 10.
Yes. It was the first to use the gravitational slingshot maneuver and got to Mercury by way of Venus.
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The second space probe to reach the planet Mercury was
(A) Pioneer 10.
(B) Mariner 4.
(C) MESSENGER.
(D) Mariner 10
(E) Pioneer 11.
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MESSENGER
It just arrived in 2008. It was a long time between probes.
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So far (as of 2008), the planet Mercury has been visited by
(A) no successful space probes.
(B) just one successful space probe.
(C) two successful space probes.
(D) about 20 successful space probes.
(E) about 48 successful space probes.
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(C) two successful space probes.
Yes. Mariner 10 in 1974 and MESSENGER in 2008.
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venus has..
(A) almost no atmosphere.
(B) an atmosphere of carbon dioxide with about 90 times the surface pressure of Earth's.
(C) an atmosphere of carbon dioxide with about 1% the surface pressure of Earth's.
(D) an atmosphere whose temperature and pressure are at the triple point of water.
(E) an atmosphere whose temperature and pressure are at the triple point of methane.
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(B) an atmosphere of carbon dioxide with about 90 times the surface pressure of Earth's.
Yes. Not a friendly place.
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Which of the following planets or moons has an atmosphere with about 90 times the surface pressure of Earth's.
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Venus
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The presence of frozen water on Venus is
(A) impossible because every part of it is too hot for water ice.
(B) possible because the planet always keeps the same side turned away from the Sun.
(C) possible because it has no axial tilt so that its poles never face the Sun.
(D) impossible because the night side, where it is cold, eventually rotates to face the Sun.
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(A) impossible because every part of it is too hot for water ice.
Yes. Its dense and active atmosphere spreads the heat around.
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Which of the following planets has the highest surface temperature?
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Venus
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Venus
(A) always keeps the same side toward the Sun so that solar time never changes.
(B) rotates backwards so that the Sun rises in the West.
(C) has a solar day that lasts for two complete orbits around the Sun.
(D) has a solar day that lasts for three complete orbits around the Sun.
(E) has a solar day that is very close to an Earth day in length.
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(B) rotates backwards so that the Sun rises in the West.
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Relative to the distant stars Venus..
(A) completes just one full rotation each time it orbits the Sun.
(B) completes 1.5 rotations each time it orbits the Sun.
(C) completes 2 rotations each time it orbits the Sun.
(D) does not rotate at all.
(E) completes less than one full rotation each time it orbits the Sun.
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(E) completes less than one full rotation each time it orbits the Sun.
Yes. On Venus, a sideareal day (243 Earth days) is longer than a sideareal year (224 Earth day).
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the magnetic field of Venus is..
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essentially zero
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Which of the following planets has no magnetic field of any kind?
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Venus (doesn't rotate fast enough)
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which of the following planets has no moons at all?
(A) Venus
(B) Earth
(C) Mars
(D) Jupiter
(E) Neptune
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venus
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The first space probes to land on another planet were from the
(A) Russian Venera series.
(B) The US Pioneer series.
(C) The European Venus Express series.
(D) The Viking series.
(E) The Voyager series.
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(A) Russian Venera series.
Yes. After many unsuccessful tries, they finally got it to work and landed it on Venus.
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The Russian Venera 9 space probe was sent to Venus, where it
(A) crashed on the surface.
(B) landed on the surface and took pictures.
(C) went into orbit and mapped the surface.
(D) received a gravitational boost on its way to Mercury.
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(B) landed on the surface and took pictures.
Yes. It lasted for almost an hour before its cooling system stopped working.
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Which of the following space probes made detailed three dimensional maps of Venus using radar from orbit around the planet?
(A) Pioneer 10
(B) Magellan
(C) MESSENGER
(D) Mariner 10
(E) Pioneer 11
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(B) Magellan
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So far (as of 2008), the planet Venus has been visited by
(A) no successful space probes.
(B) just one successful space probe.
(C) two or three successful space probes.
(D) about 20 successful space probes.
(E) about 48 successful space probes.
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(D) about 20 successful space probes.
Yes. Including eight landers sent by the Soviet Union.
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Which of these is a distinctive feature of the Earth's atmosphere?
(A) the presence of nitrogen.
(B) the presence of water vapor.
(C) the presence of carbon dioxide
(D) temperature and pressure permit all three phases of water.
(E) temperature and pressure permit all three phases of methane.
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(D) temperature and pressure permit all three phases of water.
Yes. Only here can you see icebergs floating in water with water vapor clouds in the sky.
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Which of the following planets or moons has an atmosphere whose temperature and pressure permit all three forms of water?
(A) Mercury
(B) Venus
(C) Earth
(D) Mars
(E) Titan
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earth
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Earth's orbit is currently
(A) exactly circular.
(B) slightly elliptical but not enough to affect the intensity of sunlight.
(C) elliptical enough to make the intensity of sunlight vary by 6 percent.
(D) elliptical enough to make the intensity of sunlight vary by 40 percent.(
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(C) elliptical enough to make the intensity of sunlight vary by 6 percent.
Yes. That corresponds to about a 3% difference in distance.
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At present (within the last few hundred years), the distance from the Earth to the Sun
A) never changes.
(B) changes a little, but not enough to affect the intensity of sunlight.
(C) changes enough to make the intensity of sunlight vary by 6 percent.
(D) changes enough to make the intensity of sunlight vary by 40 percent.
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(C) changes enough to make the intensity of sunlight vary by 6 percent.
Yes. That corresponds to a 3% difference between the aphelion and perihelion distances.
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Milankovich cycles refer to
(A) changes in the intensity of sunlight due to shifts in both the Earth's orbit and rotation axis.
(B) the regular shifting of the Earth's rotation axis.
(C) changes in the intensity of sunlight due to shifts in the atmosphere of the Sun and the Earth's rotation axis.
(D) changes in the intensity of sunlight due to shifts in the Earth's orbit.
(E) the regular shifting of the Earth's orbit.
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(A) changes in the intensity of sunlight due to shifts in both the Earth's orbit and rotation axis.
Yes. Sometimes they work against each other, like now, and sometimes they work together.
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Changes in the intensity of sunlight due to shifts in both the Earth's orbit and rotation axis cause
(A) the seasons.
(B) the phases of the Moon.
(C) Milankovich cycles.
(D) the precession of the equinoxes.
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(C) Milankovich cycles.
The orbital effects increase and decrease cyclically and also go in and out of phase with the seasons.
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The Earth's magnetic field plays an essential role in
(A) keeping the Moon in orbit.
(B) protecting the Earth from ultraviolet light from the Sun.
(C) protecting the Earth from charged particles from the Sun.
(D) maintaining the Earth's rotation.
(E) the manufacture of refrigerator magnets.
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(C) protecting the Earth from charged particles from the Sun.
Yes. The particles are deflected or become trapped in the Van Allen radiation belts.
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Our Sun sends out intense streams of charged particle radiation. The radiation is prevented from hitting the Earth's atmosphere by
(A) the Earth's gravitational field.
(B) the tilt of the Earth's rotation axis.
(C) the Earth's magnetic field.
(D) the Earth's Moon.
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(C) the Earth's magnetic field.
Yes. The particles cannot cross magnetic field lines, so they are deflected.
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The Earth's moon is
(A) is 1/25 the size of the Earth, which is a normal size for a moon.
(B) is 1/4 the size of the Earth, which is unusually large for a moon.
(C) is 1/500 the size of the Earth, which is unusually small for a moon.
(D) is 1/4 the size of the Earth, which is a normal size for a moon.
(E) is 1/25 the size of the Earth, which is small for a moon.
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(B) is 1/4 the size of the Earth, which is unusually large for a moon.
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The Lunar Maria are actually
(A) oceans of water.
(B) ancient lava flows.
(C) the original lunar surface.
(D) ancient dust storms.
(E) oceans of carbon disulfide.
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(B) ancient lava flows.
Yes. The young and still partly molten moon was hit by some large objects and lava flowed out onto the surface.
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The dark markings on the Full Moon that make up the face of the "Man in the Moon" are called Lunar
(A) planitia.
(B) maria.
(C) craters.
(D) valleys.
(E) terrae.
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(B) maria.
Yes. That is latin for 'sea'. The Maria look sort of like oceans and are actually frozen oceans of lava.
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The number of maria on the side of the Moon facing away from the Earth is
(A) about the same as on the side facing Earth.
(B) greater than on the side facing Earth.
(C) less than on the side facing Earth.
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(C) less than on the side facing Earth.
Yes. The crust is much thicker on that side and the surface evidently did not break open to form lava flows
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The circular structures on the surface of the Moon are the result of
A) volcanos.
(B) moonquakes.
(C) impacts.
(D) gas bubbles.
(E) fortifications.
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impacts
They have depressed floors and ring-walls formed when large objects hit the Moon and made its surface splash outward.
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The Moon rotates on its axis relative to the distant stars
(A) not at all.
(B) once every sideareal month.
(C) once every sideareal day.
(D) once a year.
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Yes. It has to do that to keep the same face turned toward the Earth as it goes around the Earth each month.
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The Moon rotates on its axis so that it always keeps the same side
(A) towards the Sun.
(B) toward the Earth.
(C) toward a particular distant star.
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toward the earth
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the distance from the earth to the moon
(A) varies, but not enough to affect eclipses.
(B) is always the same.
(C) varies enough that sometimes we get an annular solar eclipse.
(D) varies enough that sometimes we get an annular lunar eclipse.
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(C) varies enough that sometimes we get an annular solar eclipse.
Yes. When the Moon is at its apogee, its angular size is too small to cover up the Sun.
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the magnetic field of Earth's moon is
(A) essentially zero.
(B) about 1% of the Earth's magnetic field.
(C) Similar in intensity to the Earth's magnetic field.
(D) about 10 times the intensity of the Earth's magnetic field.
(E) about 100 times the intensity of the Earth;s magnetic field.
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essentially zero
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the Moon's orbit
(A) is in the plane of the ecliptic.
(B) is in the plane of the Earth's equator.
(C) is perpendicular to the plane of the Earth's equator.
(D) is somewhat tilted relative to the plane of the Earth's equator.
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(D) is somewhat tilted relative to the plane of the Earth's equator.
Yes. That is one reason we do not think that it formed along with the Earth.
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The key argument against the Moon forming from the Earth alone, by breakup of a single object is that the Moon's
(A) core lacks iron.
(B) size is very large compared to Earth.
(C) orbit is tilted relative to Earth's equator.
(D) orbit is tilted relative to the ecliptic.
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(C) orbit is tilted relative to Earth's equator.
Yes. A fission model would have the Moon orbit exactly in the plane of Earth's equator.
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The statement that lunar material is much "dryer" than Earth material refers to the absence of
(A) liquid water.
(B) ice.
(C) mud.
(D) hydrated minerals.
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D) hydrated minerals.
Yes. Those could be present in a vacuum but they are not.
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The currently accepted theory of how the Moon formed is the
(A) capture theory.
(B) co-formation theory.
(C) breakup or fission theory.
(D) collision theory.
(E) divine intervention theory.
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(D) collision theory.
Yes. Also known as the 'Big Splash' theory. It is messy but detailed computer models show that it can account for all of the observed properties of our Moon.
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The first successful soft landing on the Moon was Surveyor 1 in
A) 1958.
(B) 1966.
(C) 1969.
(D) 1972
(E) 1974.
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1966
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The first successful soft landing on the Moon was
(A) Surveyor 1 in 1969.
(B) Surveyor 1 in 1966.
(C) Luna 21 in 1973.
(D) Luna 21 in 1976.
(E) Apollo 10 in 1969.
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(B) Surveyor 1 in 1966.
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The first human landing on the moon was
(A) Apollo 10 in 1969.
(B) Apollo 11 in 1969.
(C) Apollo 10 in 1974.
(D) Apollo 11 in 1974.
(E) Surveyor 1 in 1969.
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Apollo 11 in 1969
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Since the last Apollo mission to the Moon and the last Soviet LUNA sample-return mission
(A) there have been no spacecraft sent there at all.
(B) spacecraft began to be sent there again starting in 1980.
(C) spacecraft began to be sent there again starting in 1990.
(D) spacecraft began to be sent there again starting in 2003.
(E) spacecraft began to be sent there again starting in 2007.
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(C) spacecraft began to be sent there again starting in 1990.
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Mars has
(A) almost no atmosphere.
(B) an atmosphere of carbon dioxide with about 90 times the surface pressure of Earth's.
(C) an atmosphere of carbon dioxide with about 1% the surface pressure of Earth's
(D) an atmosphere whose temperature and pressure permit all three forms of water.
(E)an atmosphere whose temperature and pressure are at the triple point of methane.
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(C) an atmosphere of carbon dioxide with about 1% the surface pressure of Earth's
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The range of temperatures on Mars is
(A) much hotter than anywhere on Earth.
(B) Similar to those in Rochester New York.
(C) Similar to those in Antarctica.
(D) Much colder than anywhere on Earth.
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(C) Similar to those in Antarctica.
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Which of the following temperatures would be most likely at noon on the hottest day of the year in the warmest part of Mars?
(A) -150F.
(B) -200F.
(C) 50F.
(D) 100F.
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50F
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In the surface Environment of Mars, water exists
(A) in all three forms, solid, liquid, and gas.
(B) Mostly as ice and water vapor.
(C) Only as ice.
(D) Only as water vapor.
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(B) Mostly as ice and water vapor.
Yes. At that low pressure, the boiling point of water is only a little above the freezing point.
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On the present surface of Mars, water has been confirmed to exist
(A) as small streams of liquid water.
(B) as oceans.
(C) as ice at the poles and water vapor in the atmosphere.
(D) nowhere at all. The planet is completely dry.
answer
C) as ice at the poles and water vapor in the atmosphere.
