TF阅读真题第902篇Tidal Heating on lo

Tidal Heating on lo

 

 

To understand tidal heating, we must go back to when the twin spacecraft Voyager 1 and Voyager 2 made close flybys of the moon lo, Jupiter’s closest moon. lo had been a priority for both Voyager spacecraft as a visit made five years earlier by another United States spacecraft, Pioneer 11, hinted at a brightly colored yet undetermined surface. Astronomers were intrigued, and the trajectories (paths in space) of both Voyager spacecraft were conceived in such a way that close flybys of lo could be performed. When the high-resolution images from the Voyager spacecraft came back, they revealed an active world, but unlike the icy but active neighboring moon Europa, this one was hot. lo was a dream world for volcanologists. The moon was peppered with volcanic calderas and tall mountains, upon which eruption plumes and lava flows, stained yellow and red by oxides of sulfur, would emerge. Remarkably, the surface seemed not to have a single impact crater, suggesting that the moon’s surface was continually being renewed by volcanic activity. Io had a lot of energy.

Finding such an active world lying far away from the Sun was astonishing and led to a hunt for the source of lo’s energy. The explanation came from a paper by Stanton Peale and his colleagues published in the prestigious journal Science just a few days before Voyager 1’s arrival in the Jupiter system. The paper proposed that lo could be experiencing warming as it orbits Jupiter in a noncircular orbit (elliptical orbit), which produces variations in the gravity pull from the giant planet. This process was named tidal heating, and it didn’t take long for this new theory to be accepted by the scientific community as the primary heat source driving lo’s intense warming. What goes on inside lo can be easily demonstrated by using a simple metal wire. If you flex one part of the wire backward and forward, it won’t take long for heat to be felt in the bent part. The explanation is simple. Some of the kinetic energy was transformed into heat through internal friction. A similar process also makes squash balls warm after a match.

The reason behind lo’s energy output is its elliptic orbit resulting from a phenomenon known as orbital resonance, which locks each of Jupiter’s four largest moons into a specific orbital ratio around Jupiter. For every two orbits that lo takes around the planet, Europa takes precisely one orbit. Due to orbital mechanics, both moons always come closest to each other at the same location within their orbits, pulling lo closer to Europa, thus making its orbit elliptical instead of circular. Elliptical orbits are measured by their eccentricity. The greater the eccentricity, the more elliptical the orbit will be and vice versa.

Since lo’s orbit around its giant parent planet is not a circular one but an elliptical one, the moon will feel Jupiter’s gravitational pull differently along its orbit. This is referred to as tidal forces and is similar to the gravitational effect our Moon has on the seas and oceans of Earth. On lo, the tidal forces will be most influential during the moon’s closest approach in orbit (periapsis) and least during its furthest point (apoapsis). As it moves from periapsis to apoapsis and back, the tidal forces pull lo at varying intensities, thus creating friction and generating heat as the moon’s interior repeatedly distorts and buckles.

Of course, many factors determine how much impact tidal forces can have on an object. The size of the moon in relation to its parent planet as well as the distance of the moon’s orbit will be determining factors. As importantly, the composition of the moon itself will dictate how strongly it responds to these distortions. If the object is rocky, like our Moon, it will distort far less than if it is made entirely of ice. By analyzing its orbit around Jupiter, astronomers deduced that lo has roughly the same density as silicate rock, which means that the inside of the moon must consist mainly of rocky material. This material is flexible enough to be affected by Jupiter’s strong gravitational pull, but not so fragile as to be pulled apart by it. Therefore, the rocky core and mantle get stretched in orbit, producing considerable heat through friction, which fuels the volcanism on the surface.

 

 

 

 

 

 

1

To understand tidal heating, we must go back to when the twin spacecraft Voyager 1 and Voyager 2 made close flybys of the moon lo, Jupiter’s closest moon. lo had been a priority for both Voyager spacecraft as a visit made five years earlier by another United States spacecraft, Pioneer 11, hinted at a brightly colored yet undetermined surface. Astronomers were intrigued, and the trajectories (paths in space) of both Voyager spacecraft were conceived in such a way that close flybys of lo could be performed. When the high-resolution images from the Voyager spacecraft came back, they revealed an active world, but unlike the icy but active neighboring moon Europa, this one was hot. lo was a dream world for volcanologists. The moon was peppered with volcanic calderas and tall mountains, upon which eruption plumes and lava flows, stained yellow and red by oxides of sulfur, would emerge. Remarkably, the surface seemed not to have a single impact crater, suggesting that the moon’s surface was continually being renewed by volcanic activity. Io had a lot of energy.

Paragraph 1 supports which of the following statements about the Voyager 1 and Voyager 2 spacecraft?

Factual Information Questions事实信息题

AThey were the first United States spacecraft to have specially designed trajectories.

BThey were designed to help scientists understana tidal heating.

CThey were the first spacecraft to image the surface of Jupiter’s closest moon, lo.

DTheir flight plans were developed in part in response to the findings of Pioneer 11.

 

2

To understand tidal heating, we must go back to when the twin spacecraft Voyager 1 and Voyager 2 made close flybys of the moon lo, Jupiter’s closest moon. lo had been a priority for both Voyager spacecraft as a visit made five years earlier by another United States spacecraft, Pioneer 11, hinted at a brightly colored yet undetermined surface. Astronomers were intrigued, and the trajectories (paths in space) of both Voyager spacecraft were conceived in such a way that close flybys of lo could be performed. When the high-resolution images from the Voyager spacecraft came back, they revealed an active world, but unlike the icy but active neighboring moon Europa, this one was hot. lo was a dream world for volcanologists. The moon was peppered with volcanic calderas and tall mountains, upon which eruption plumes and lava flows, stained yellow and red by oxides of sulfur, would emerge. Remarkably, the surface seemed not to have a single impact crater, suggesting that the moon’s surface was continually being renewed by volcanic activity. Io had a lot of energy.

According to paragraph 1, all of the following are true of the moon lo EXCEPT:

Negative Factual Information Questions否定事实信息题

AIt has a mountainous surface.

BOxides of sulfur color its surface.

CIts surface is peppered with impact craters.

DVolcanic materials continuously renew its surface.

 

3

Finding such an active world lying far away from the Sun was astonishing and led to a hunt for the source of lo’s energy. The explanation came from a paper by Stanton Peale and his colleagues published in the prestigious journal Science just a few days before Voyager 1’s arrival in the Jupiter system. The paper proposed that lo could be experiencing warming as it orbits Jupiter in a noncircular orbit (elliptical orbit), which produces variations in the gravity pull from the giant planet. This process was named tidal heating, and it didn’t take long for this new theory to be accepted by the scientific community as the primary heat source driving lo’s intense warming. What goes on inside lo can be easily demonstrated by using a simple metal wire. If you flex one part of the wire backward and forward, it won’t take long for heat to be felt in the bent part. The explanation is simple. Some of the kinetic energy was transformed into heat through internal friction. A similar process also makes squash balls warm after a match.

The word ” prestigious “in the passage is closest in meaning to

Vocabulary Questions词汇题

Acarefully reviewed

Brespected

Cwidely distributed

Dindependent

 

4

Finding such an active world lying far away from the Sun was astonishing and led to a hunt for the source of lo’s energy. The explanation came from a paper by Stanton Peale and his colleagues published in the prestigious journal Science just a few days before Voyager 1’s arrival in the Jupiter system. The paper proposed that lo could be experiencing warming as it orbits Jupiter in a noncircular orbit (elliptical orbit), which produces variations in the gravity pull from the giant planet. This process was named tidal heating, and it didn’t take long for this new theory to be accepted by the scientific community as the primary heat source driving lo’s intense warming. What goes on inside lo can be easily demonstrated by using a simple metal wire. If you flex one part of the wire backward and forward, it won’t take long for heat to be felt in the bent part. The explanation is simple. Some of the kinetic energy was transformed into heat through internal friction. A similar process also makes squash balls warm after a match.

In paragraph 2, why does the author discuss “metal wire” and “squash balls”?

Rhetorical Purpose Questions修辞目的题

ATo help explain how tidal heating occurs on lo

BTo demonstrate how Stanton Peale and his colleagues developed the theory of warming on lo

CTo suggest that obiects made of completely different materials can experience internal friction

DTo help the reader understand the difference between a noncircular orbit and a circular orbit

 

5

The reason behind lo’s energy output is its elliptic orbit resulting from a phenomenon known as orbital resonance, which locks each of Jupiter’s four largest moons into a specific orbital ratio around Jupiter. For every two orbits that lo takes around the planet, Europa takes precisely one orbit. Due to orbital mechanics, both moons always come closest to each other at the same location within their orbits, pulling lo closer to Europa, thus making its orbit elliptical instead of circular. Elliptical orbits are measured by their eccentricity. The greater the eccentricity, the more elliptical the orbit will be and vice versa.

According to paragraph 3, which TWO of the following are factors that contribute to lo’s elliptical orbit? To receive credit, you must select TWO answer choices.

Factual Information Questions事实信息题

Select 2 answers

Alo being locked into a specific orbital ratio with three other moons

Blo taking a longer time than Europa to orbit Jupiter

Clo being pulled closer to Europa where the two moons come closest to each other

Dlo’s energy output increasing with its eccentricity

 

6

Since lo’s orbit around its giant parent planet is not a circular one but an elliptical one, the moon will feel Jupiter’s gravitational pull differently along its orbit. This is referred to as tidal forces and is similar to the gravitational effect our Moon has on the seas and oceans of Earth. On lo, the tidal forces will be most influential during the moon’s closest approach in orbit (periapsis) and least during its furthest point (apoapsis). As it moves from periapsis to apoapsis and back, the tidal forces pull lo at varying intensities, thus creating friction and generating heat as the moon’s interior repeatedly distorts and buckles.

According to paragraph 4, lo’s movement from periapsis to apoapsis results in which of the following?

Factual Information Questions事实信息题

Alo experiences tidal forces of different strengths.

Blo’s orbit becomes more elliptical over time.

Clo’s orbit gets closer and closer to Jupiter.

Dlo’s effect on Jupiter becomes more like our Moon’s effect on Earth’s seas and oceans.

 

7

Of course, many factors determine how much impact tidal forces can have on an object. The size of the moon in relation to its parent planet as well as the distance of the moon’s orbit will be determining factors. As importantly, the composition of the moon itself will dictate how strongly it responds to these distortions. If the object is rocky, like our Moon, it will distort far less than if it is made entirely of ice. By analyzing its orbit around Jupiter, astronomers deduced that lo has roughly the same density as silicate rock, which means that the inside of the moon must consist mainly of rocky material. This material is flexible enough to be affected by Jupiter’s strong gravitational pull, but not so fragile as to be pulled apart by it. Therefore, the rocky core and mantle get stretched in orbit, producing considerable heat through friction, which fuels the volcanism on the surface.

Paragraph 5 supports the idea that if lo were made of ice

Factual Information Questions事实信息题

Aits orbit would be closer to jJupiter than it actually is

Bit would distort considerably more than it actually does

Cits response to distortions would more resemble that of our Moon than it actually does

Dit would produce less heat than it actually does

 

8

Of course, many factors determine how much impact tidal forces can have on an object. The size of the moon in relation to its parent planet as well as the distance of the moon’s orbit will be determining factors. As importantly, the composition of the moon itself will dictate how strongly it responds to these distortions. If the object is rocky, like our Moon, it will distort far less than if it is made entirely of ice. By analyzing its orbit around Jupiter, astronomers deduced that lo has roughly the same density as silicate rock, which means that the inside of the moon must consist mainly of rocky material. This material is flexible enough to be affected by Jupiter’s strong gravitational pull, but not so fragile as to be pulled apart by it. Therefore, the rocky core and mantle get stretched in orbit, producing considerable heat through friction, which fuels the volcanism on the surface.

According to paragraph 5, all of the following are factors that determine how much impagt tidal forces can have on a moon EXCEPT:

Negative Factual Information Questions否定事实信息题

AThe relative sizes of the moon and planet

BThe distance of the moon’s orbit from the planet

CWhat materials the moon is made of

DThe amount of heat produced by other forces

 

9

To understand tidal heating, we must go back to when the twin spacecraft Voyager 1 and Voyager 2 made close flybys of the moon lo, Jupiter’s closest moon. ⬛lo had been a priority for both Voyager spacecraft as a visit made five years earlier by another United States spacecraft, Pioneer 11, hinted at a brightly colored yet undetermined surface. ⬛Astronomers were intrigued, and the trajectories (paths in space) of both Voyager spacecraft were conceived in such a way that close flybys of lo could be performed. When the high-resolution images from the Voyager spacecraft came back, they revealed an active world, but unlike the icy but active neighboring moon Europa, this one was hot.⬛ lo was a dream world for volcanologists. The moon was peppered with volcanic calderas and tall mountains, upon which eruption plumes and lava flows, stained yellow and red by oxides of sulfur, would emerge. ⬛Remarkably, the surface seemed not to have a single impact crater, suggesting that the moon’s surface was continually being renewed by volcanic activity. Io had a lot of energy.

Look at the four squaresthat indicate where the following sentence could be added to the passage

Because of this,lupiter’s closest moon intrigued more than iust astronomers.

Insert Text Questions句子插入题

Where would the sentence best fit？Click on a square  sentence to the passage.

10

The images of lo that came back from the Voyager spacecraft revealed a volcanically active world far from the Sun.

Prose Summary Questions概要小结题

Select 3 answers

AThe Voyager missions were sent to lo to confirm that lo was frozen and inactive, as had been hinted at by earlier spacecraft, but their findings surprised astronomers.

BThe noncircular nature of lo’s orbit, which results from Europa’s gravitational influence when the two moons are close, contributes to lo’s warming.

CDifferences in the way that lo experiences Jupiter’s gravitational pull during its orbit result in tidal forces that warm lo through friction, causing volcanic activity on its surface.

DThe rocky material that is thought to make up most of lo’s interior is an important contributor to the effects of the tidal forces lo experiences as it is flexible but strong enough not to break apart.

EThe periodic renewal of lo’s surface through volcanism affects the impact of tidal forces on lo’s surface, accounting for variations in distortion and buckling.

FWhile the tidal forces that Jupiter exerts on lo are similar to those that affect Earth’s moon, they differ in terms of when they are most influential.