单选题Only a small part of the sun’s energy reaches the earth’ s surface because most of it is ______.A absorbed by the clouds in the lower atmosphereB reflected by the gases in the upper atmosphereC lost in the upper and lower atmosphereD used to evaporate water from the oceans and lakes

考题 When people speak of solar energy, they only think of sun’s rays heating a home or ________ electricity from the sun. A.deriveB.to deriveC.derivingD.of deriving.

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考题 It is a common sense that the earth is ( ). A、one of the suns’ planetsB、one of the sun's planetsC、one of the sun’s planetD、one of the suns’ planet’s

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考题 Antarctica isn't only the coldest place on Earth, it's also one of the world's driest deserts.

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考题 That's only ___ of the story.A、a partB、some partC、partD、any part

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考题 Which of the following statements in supported by the passage?A．The sun shines constantly and gives out the same amount of energy every year．B．The cause of the sun’S fluctuations is its loss of energy with each passing yearC．It is sure that the energy sent out by the sun will drop when more sun spots appear．D．Fluctuations in weather pattems are the results of the pull of gravity．

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考题 A mean sun is used as the reference for solar time for three reasons. Which reason is NOT a cause for use of a mean sun?A.The motion of the apparent sun is along the eclipticB.Measurement of time is along the celestial equatorC.The speed of the Earth's revolution is not constantD.There are variations in the Earth's rotational speed

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考题共用题干 The Northern LightsThe Sun is stormy and has its own kind of weather It is so hot and active that even the Sun's gravity cannot hold its atmosphere in check!Energy flows away from the Sun toward the Earth in a stream of electrified particles that move at speeds around a million miles per hour. These particles are called plasma,and the stream of plasma coming from the Sun is called the solar wind. The more active the Sun,the stronger the solar wind.The solar wind constantly streams toward the Earth,but don't worry because a protective magnetic field surrounds our planet.The same magnetic field that makes your compass point north also steers the particles from the Sun to the north and south poles.The charged particles become trapped in magnetic belts around the Earth. When a large blast of solar wind crashes into the Earth's magnetic field,the magnetic field first gets squeezed and then the magnetic field lines break and reconnect.The breaking and reconnecting of the magnetic field lines can cause atomic particles called electrons trapped in the belts to fall into the Earth's atmosphere at the poles. As the electrons fall to the Earth,they collide with gas molecules in the atmosphere,creating flashes of light in the sky. Each atmospheric gas glows a different color. Oxygen and nitrogen glows red and green and nitrogen glows violet-purple. As these various colors glow and dance in the night sky,they create the Northern Lights and the Southern Lights.Watching auroras is fun and exciting,but normally you can only see them in places far north like Alaska and Canada. The movement of the aurora across the sky is usually slow enough to easily follow with your eyes but they can also pulsate,flicker,or even move like waves.During solar maximum,auroras are seen as far south as Florida,even Mexico!Auroras often seem to be very close to the ground,but the lowest aurora is still about 100 kilometers above the ground,a distance much higher than clouds are formed or airplanes can fly. A typical aurora band can be thousands of kilometers long,a few hundred kilometers high,but only a few hundred meters thick.We hope you are able to travel to far north places like the Arctic Circle and see the Northern Lights at least once during your lifetime. We know you will never forget it!The Sun's gravity is too weak to keep its plasma from flowing to the Earth.A: RightB: WrongC: Not mentioned

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考题 Mercury’s（）is so much greater than the Earth’s that it completes more than four revolutions around the Sun in the time it takes the Earth to complete one.A.velocity B.orbit C.weight D.diameter

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考题共用题干第一篇The Northern LightsThe sun is stormy and has its own kind of weather.It is so hot and active that even the Sun's gravity cannot hold its atmosphere in check!Energy flows away from the Sun toward the Earth in a stream of electrified particles that move at speeds around a million miles per hour.These particles are called plasma （等离子体）,and the stream of plasma coming from the Sun is called the solar wind.The more active the Sun,the stronger the solar wind.The solar wind constantly streams toward the Earth,but don't worry because a protective magnetic field surrounds our planet.The same magnetic field that makes your compass point north also steers the particles from the Sun to the north and south poles.The charged particles become trapped in magnetic belts around the Earth.When a large blast of solar wind crashes into the Earth's magnetic field,the magnetic field first gets squeezed and then the magnetic field lines break and reconnect.The breaking and reconnecting of the magnetic field lines can cause atomic particles called electrons trapped in the belts to fall into tile Earth's atmosphere at the poles.As the electrons fall to the Earth,they collide with gas molecules in the atmosphere,creating flashes of light in the sky.Each atmospheric gas glows a different color.Oxygen and nitrogen glows red and green arid nitrogen glows violet purple.As these various colors glow and dance in the night sky,they create the Northern Lights and the Southern Lights.Watching auroras（北极光）is fun and exciting, but normally you can only see them in places far north like Alaska and Canada.The movement of the aurora across the sky is usually slow enough to easily follow with your eyes but they can also pulsate（跳动）,flicker（闪烁）,or even move like waves.During solar maximum,5 auroras are seen as far south as Florida,even Mexico!Auroras often seem to be very close to the ground,but the lowest aurora is still about 100 kilometers above the ground,a distance much higher than clouds are formed or airplanes can fly.A typical aurora band can be thousands of kilometers long,a few hundred kilometers high,but only a few hundred meters thick.We hope you are able to travel to far north places like the Arctic Circle and see the Northern Lights at least once during your lifetime.We know you will never forget it!The solar wind comes into being as a result of_______.A:disappearance of the Sun's gravityB:unpredictable weather of the SunC:fast flow of energy away from the SunD:a stream of particles being blown away

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考题共用题干 New Comet FoundThere's a newfound comet closing in on the sun,and when it gets here in 2013,you may be able to see it with your naked eye.Astronomers stumbled upon the icy interloper on June 5 while searching for potentially hazardous asteroids（小行星）.Equipped with the world's largest digital camera , the University of Hawaii's Pan-STARRS team snagged a faint image of the odd object while it was more than 700 million miles away , between the orbits of Jupiter（木星）and Saturn（土星）."Almost everything we find is an asteroid,but this object was suspicious,"said Richard Wainscoat,co-discoverer of the comet and an astronomer at the University of Hawaii."Unlike asteroids, which appear point-like in images,the telltale sign that gave it away was its fuzzy appearance."By March 2013 the comet,named C/2011 L4(PANSTARRS),is expected to come within 30 million miles of the sun一closer even than the innermost（最深处）planet, Mercury（水星）.When the comet makes its closest approach to the sun,most of its ices will vaporize,adding to its hazy envelope of gas and dust and producing the familiar tail. This denser envelope,or coma, should boost the comet to peak brightness,making it potentially visible to the naked eye low in the western horizon just after sunset.While there is no danger of collision with Earth,preliminary calculations of the comet's orbit show that this may be its first and final trip through the solar system."It may be coming around the sun for the first and only time,only to be ejected from the solar system,never to return,"Wainscoat said."Since we don't have a lot of data on it,we really don't know the orbit well enough right now, and it will take up to two months of observations to find out."Astronomers believe C/2011 L4 may be a runaway from the Oort cloud（奥尔特云）,a reservoir of billions of hibernating（蛰伏）comets that orbits about 100,000 times farther than the distance between Earth and the sun.The fact that it's going around the back of the sun from our point of view may ultimately affect the comet's visibility,but a lot will depend on how close the body actually gets to the sun.Also, whether the comet is north or south of the sun when it reaches peak brightness will determine which hemisphere on Earth gets the better view.The newfound comet is made from mercury.A:Right B:Wrong C:Not mentiond

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考题共用题干 Where Did the Earth's Water Come From?Earth is located within the"snow line"of the solar system,the region closest to the Sun where H2 0 is primarily in liquid or gaseous form,if at all.______(46)The snow line phenomena is reflected in the water content of planets like Mercury,Venus,and Mars. Water is absent on Mercury.On Venus,H2O only exists as a trace element in the atmosphere.Mars only has a thin veneer of ice in its polar regions.In general,water is rare within the snow line.Why does Earth have so much water relative to the other inner planets?71%of the surface is covered in the oceans,more than half of which is deeper than 3,000 meters,with an approximate total volume of 1.3 billion cu km.______(47)There are various theories as to where all the Earth's water came from,but several theories have fared better than the others.______(48)When the Earth was in the process of forming,with a radius just 40%smaller than at present,it would have had enough gravity to hold on to a tenuous atmosphere with water vapor. The first water vapor on the planet would have come from the planet's internals,where volatile(low weight)chemicals would have a tendency to float to the top,and heavy chemicals(iron and nickel)would sink.Though the first of Earth's water came about through volcanism,this alone probably didn't produce enough to form stable pools on the surface.______(49)Comparing the isotope ratios of water on Earth and water from comets and asteroids has revealed that the majority of the Earth's water comes from asteroids.Throughout its history,Earth's water has increased in volume due to biological processes. In the early seas of Earth,hydrogen sulfide would have been in great supply,which,when reacted with carbon dioxide from the atmosphere during photosynthesis in sulfide-reducing bacteria,would have produced hydrogen,sulfur,and water.______(50)________（49）A: More water was added to the planet during several hypothesized large impacts from asteroids from the outer asteroid belt.B:We know that the oceans existed as early as 100 million years after the formation of the Earth.C:Still,the oceans only make up 0.023%of the Earth's total mass.D:Astronomers say Earth s water may have come from space.E:The snow line is located in the outerasteroid belt,between the orbits of Mars and Jupiter. F: Many geologists believe that the majority of Earth's water generated through this process.

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考题共用题干 New Comet FoundThere's a newfound comet closing in on the sun,and when it gets here in 2013,you may be able to see it with your naked eye.Astronomers stumbled upon the icy interloper on June 5 while searching for potentially hazardous asteroids（小行星）.Equipped with the world's largest digital camera , the University of Hawaii's Pan-STARRS team snagged a faint image of the odd object while it was more than 700 million miles away , between the orbits of Jupiter（木星）and Saturn（土星）."Almost everything we find is an asteroid,but this object was suspicious,"said Richard Wainscoat,co-discoverer of the comet and an astronomer at the University of Hawaii."Unlike asteroids, which appear point-like in images,the telltale sign that gave it away was its fuzzy appearance."By March 2013 the comet,named C/2011 L4(PANSTARRS),is expected to come within 30 million miles of the sun一closer even than the innermost（最深处）planet, Mercury（水星）.When the comet makes its closest approach to the sun,most of its ices will vaporize,adding to its hazy envelope of gas and dust and producing the familiar tail. This denser envelope,or coma, should boost the comet to peak brightness,making it potentially visible to the naked eye low in the western horizon just after sunset.While there is no danger of collision with Earth,preliminary calculations of the comet's orbit show that this may be its first and final trip through the solar system."It may be coming around the sun for the first and only time,only to be ejected from the solar system,never to return,"Wainscoat said."Since we don't have a lot of data on it,we really don't know the orbit well enough right now, and it will take up to two months of observations to find out."Astronomers believe C/2011 L4 may be a runaway from the Oort cloud（奥尔特云）,a reservoir of billions of hibernating（蛰伏）comets that orbits about 100,000 times farther than the distance between Earth and the sun.The fact that it's going around the back of the sun from our point of view may ultimately affect the comet's visibility,but a lot will depend on how close the body actually gets to the sun.Also, whether the comet is north or south of the sun when it reaches peak brightness will determine which hemisphere on Earth gets the better view.The ices of the comet will vaporize while heading to the sun.A:Right B:Wrong C:Not mentiond

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考题共用题干 New Comet FoundThere's a newfound comet closing in on the sun,and when it gets here in 2013,you may be able to see it with your naked eye.Astronomers stumbled upon the icy interloper on June 5 while searching for potentially hazardous asteroids（小行星）.Equipped with the world's largest digital camera , the University of Hawaii's Pan-STARRS team snagged a faint image of the odd object while it was more than 700 million miles away , between the orbits of Jupiter（木星）and Saturn（土星）."Almost everything we find is an asteroid,but this object was suspicious,"said Richard Wainscoat,co-discoverer of the comet and an astronomer at the University of Hawaii."Unlike asteroids, which appear point-like in images,the telltale sign that gave it away was its fuzzy appearance."By March 2013 the comet,named C/2011 L4(PANSTARRS),is expected to come within 30 million miles of the sun一closer even than the innermost（最深处）planet, Mercury（水星）.When the comet makes its closest approach to the sun,most of its ices will vaporize,adding to its hazy envelope of gas and dust and producing the familiar tail. This denser envelope,or coma, should boost the comet to peak brightness,making it potentially visible to the naked eye low in the western horizon just after sunset.While there is no danger of collision with Earth,preliminary calculations of the comet's orbit show that this may be its first and final trip through the solar system."It may be coming around the sun for the first and only time,only to be ejected from the solar system,never to return,"Wainscoat said."Since we don't have a lot of data on it,we really don't know the orbit well enough right now, and it will take up to two months of observations to find out."Astronomers believe C/2011 L4 may be a runaway from the Oort cloud（奥尔特云）,a reservoir of billions of hibernating（蛰伏）comets that orbits about 100,000 times farther than the distance between Earth and the sun.The fact that it's going around the back of the sun from our point of view may ultimately affect the comet's visibility,but a lot will depend on how close the body actually gets to the sun.Also, whether the comet is north or south of the sun when it reaches peak brightness will determine which hemisphere on Earth gets the better view.C/2011 L4 will hit Earth in 2013.A:Right B:Wrong C:Not mentiond

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考题单选题An amplitude of the Sun in high latitudes（）.A is most accurate before sunriseB is most accurate after sunsetC should only be observed when the Sun's lower limb is above the horizonD is most accurate when the Sun's center is observed on the visible horizon

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考题单选题A plane that cuts the Earth’s surface and passes through the poles will always form（）.A the equatorB a loxodromic curveC a small circleD a meridian

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考题单选题Opposition occurs when（）.A the Sun，Earth，and Moon are at right anglesB the Sun's declination is 0°and is moving southC an inferior planet is at the maximum angle to the line of sight to the SunD the Earth is between a planet and the Sun

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考题单选题Written in central Canada in the early part of the twentieth century, _______ , depicts life in Manitoda.A The Midnight Sunwas Victor Frank’s last novelB Victor Frank’s last novel was The Midnight SunC The Midnight Sun, which was Victor Frank’s last novelD Which was Victor Frank’s last novel, The Midnight Sun

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考题单选题According to the passage, the greatest part of the solar energy that reaches the Earth is _____.A reflected back to space by snow and iceB concentrated at visible wavelengthsC absorbed by carbon dioxide moleculesD absorbed by atmospheric water vapor

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考题单选题An artificial sweetener, such as aspartame or sucralose, is said to contain no calories by the body’s not converting it into energy.A by the body’s not converting it into energyB by the body’s not convening them into energyC because the body does not convert them into energyD due to the body’s not converting the energy in themE because the body does not convert it into energy

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考题单选题According to the passage, _____.A we should not worry about the transition of the Earth’s magnetic fieldB the Earth’s magnetic field will not change for at least 2000 yearsC the Earth’s magnetic field has decreased its strength rapidlyD the transition of the Earth’s magnetic field can be controlled by modern science

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考题单选题A mean sun is used as the reference for solar time for three reasons. Which reason is NOT a cause for use of a mean sun?（）A The motion of the apparent sun is along the eclipticB Measurement of time is along the celestial equatorC The speed of the Earth's revolution is not constantD There are variations in the Earth's rotational speed

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考题单选题Without the sun’s light _____ the earth’s surface, it would be so cold that life could not exist on the earth.A warmsB warmedC warmingD to warm

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考题单选题A plane that cuts the Earth’s surface at any angle and passes through the center will always form（）.A the equatorB a great circleC a small circleD a meridian

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考题单选题We learn from the passage that ______.A all living things on the earth depend on the sun for their foodB a forest looks dark in winter because it absorbs solar energyC only 0.023 of the energy from the sun is made use of on the earthD greenhouse gases allow heat energy to escape from the earth’ s surface

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考题单选题The village used to be small, and had only a few streets. There were only three shops: ______ and the General Store.A the butchers’, the bakers’B the butchers, the bakersC butchers, bakersD the butcher’s, the baker’s

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考题单选题Written in central Canada in the early part of the twentieth century, _____, depicts life in Manitoda.A The Midnight Sun was Victor Frank’s last novelB Victor Frank’s last novel was The Midnight SunC The Midnight Sun, which was Victor Frank’s last novelD Which was Victor Frank’s last novel, The Midnight Sun

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考题单选题Planetary aberration is due，in part，to（）.A refraction of light as it enters the Earth's atmosphereB rotation of the Earth on it's axisC the body's orbital motion during the time required for its light to reach EarthD a false horizon

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