在托福考試中，天文學科也從來都是被重點考察的學科之一。下面是小編整理的兩道關於天文學的託福閱讀習題，希望對大家有用，更多訊息請關注應屆畢業生網。
第一道題目來自於TPO 8 Running Water on Mars
Paragraph 2: Outflow channels are probably relics of catastrophic flooding on Mars long ago. They appear only in equatorial regions and generally do not form extensive interconnected networks. Instead, they are probably the paths taken by huge volumes of water draining from the southern highlands into the northern plains. The onrushing water arising from these flash floods likely also formed the odd teardrop-shaped “islands” (resembling the miniature versions seen in the wet sand of our beaches at low tide) that have been found on the plains close to the ends of the outflow channels. Judging from the width and depth of the channels, the flow rates must have been truly enormous-perhaps as much as a hundred times greater than the 105 tons per second carried by the great Amazon river. Flooding shaped the outflow channels approximately 3 billion years ago, about the same times as the northern volcanic plains formed.
Question: According to paragraph 2, all of the following are true of the outflow channels on Mars EXCEPT:
A. They formed at around the same time that volcanic activity was occurring on the northern plains.
B. They are found only on certain parts of the Martian surface.
C. They sometimes empty onto what appear to have once been the wet sands of tidal beaches.
D. They are thought to have carried water northward from the equatorial regions.
解析：題幹問的是原文關於“outflow channels”的描述。在真正考試中，把原文閱讀完畢再去和選項比較會花費較多時間。因此，比較合理的做題順序是，先讀選項，然後拿選項和原文資訊去比對。
A選項說的是outflow channel的形成時間和火山活動在北部平原的'發生時間是相同的。快速瀏覽原文，只有在最後一句提到了它們的形成時間，說大概在30億年前，about引導的時間狀語很重要，補充說明了這一時間和北部火山平原形成的時間相同。A正確。
B選項說的是火山形成的地點，只在火星表面的特定區域。看原文，第二句，說的是它們只在赤道區域出現。B也正確。
C選項說的是它們有時候會流到曾經的溼沙地上。原文在提到tidal beaches時，並沒有提到這一資訊，因此，C選項是不符合原文的。
D選項說的是河水從赤道(南)向北流動。和原文第三句話吻合：這些河流的走向是從南部高低到北部平原。
因此，本題的正確答案為C項。
第二道題目來自於 TPO 16 Planets in Our Solar System
Paragraph 4: Other dimensions along which the two groups differ markedly are density and composition. The densities of the terrestrial planets average about 5 times the density of water, whereas the Jovian planets have densities that average only 1.5 times the density of water. One of the outer planets, Saturn, has a density of only 0.7 that of water, which means that Saturn would float in water. Variations in the composition of the planets are largely responsible for the density differences. The substances that make up both group of planets are divided into three groups-gases, rocks, and ices-based on their melting points. The terrestrial planets are mostly rocks: dense rocky and metallic material, with minor amounts of gases. The Jovian planets, on the other hand, contain a large percentage of the gases hydrogen and helium, with varying amounts of ices: mostly water, ammonia, and methane ices.
Question: Paragraph 4 mentions which of the following as a reason why terrestrial planets are dense?
A. They are made up of three groups of substances.
B. They are composed mainly of rocky and metallic materials.
C. They contain more ice than Jovian planets.
D. They contain relatively small amounts of water.
解析：題幹問的是類地行星密度較大的原因。那我們只需將做題重點鎖定在原文描述“density”的資訊上即可。原文中含有density的句子，第一句在說類地行星的密度和其他行星的密度比。第二句說的是土星密度。第三句說到行星結構的不同影響著密度的不同。後面進一步闡釋組成行星的物質：氣體，岩石以及冰。接著又提到類地行星主要由岩石組成。顯然，這就是它密度大的原因。綜合比較，應該選B。
