A、It might have been hotter than it is today. B、It might have been a cozy habitat for life. C、It used to have more water than Ea

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问题  
Good evening. In 1959, on the day that I was born, a headline in Life magazine proclaimed “Target Venus: There May be Life There!” It told of how scientists rode a balloon to an altitude of 80,000 feet to make telescope observations of Venus’s atmosphere, and how their discovery of water raised hopes that there could be living things there. As a kid I thrilled to tales of adventure in Isaac Asimov’s juvenile science-fiction novel Lucky Starr and the Oceans of Venus.
For many of my peers, though, Venus quickly lost its romance. The very first thing that scientists discovered with a mission to another planet was that Venus was not at all the earthly paradise that fiction had portrayed. It is nearly identical to our own planet in bulk properties such as mass, density, and size. But its surface has been cooked and dried by an ocean of carbon dioxide. Trapped in the burning death-grip of a runaway greenhouse effect, Venus has long been held up as a cautionary tale for everything that could go wrong on a planet like Earth. As a possible home for alien life, it has been voted the planet least likely to succeed.
But I have refused to give up on Venus, and over the years my stubborn loyalty has been justified. The rocky views glimpsed by Venera 9 and other Russian landers suggested a tortured volcanic history. That was confirmed in the early 1990s by the American Magellan orbiter, which used radar to peer through the planet’s thick clouds and map out a rich, varied, and dynamic surface. The surface formed mostly in the last billion years, which makes it fresher and more recently active than any rocky planet other than Earth. Russian and American spacecraft also found hints that its ancient climate might have been wetter, cooler, and possibly even friendly to life. Measurements of density and composition imply that Venus originally formed out of basically the same stuff as Earth. That presumably included much more water than the tiny trace we find blowing in the thick air today.
Thus our picture of Venus at around the time life was getting started on Earth is one of warm oceans, probably rich with organic molecules, splashing around rocky shores and volcanic vents. The sun was considerably less bright back then. So, Venus was arguably a cozier habitat for life than Earth.
Questions 19 to 21 are based on the recording you have just heard.
19. What do we learn from the Life magazine article?
20. What are scientists’ findings about Venus?
21. What information did Russian and American space probes provide about Venus?

选项 A、It might have been hotter than it is today.
B、It might have been a cozy habitat for life.
C、It used to have more water than Earth.
D、It used to be covered with rainforests.

答案B

解析 讲座中提到,俄罗斯和美国的太空探测器发现了金星古时候的气候可能比现在更加湿润、清凉,比现在更加适合生物生存的线索。因此答案为B)。
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