Space is a dangerous place, not only because of meteors but also because of

游客2023-11-19 67

问题 Space is a dangerous place, not only because of meteors but also because of rays from the sun and other stars. The atmosphere again acts as our protective blanket on earth. Light gets through, and this is essential for plants to make the food which we eat. Heat, too, makes our environment endurable. Various kinds of rays come through the air from outer space, but enormous quantities of radiation from the sun are screened off. As soon as men leave the atmosphere they are exposed to this radiation but their space suits or the walls of their spacecraft, if they are inside, do prevent a lot of radiation damage.
Radiation is the greatest known danger to explorers in space. The unit of radiation is called "rem". Scientists have reason to think that a man can put up with far more radiation than 0.1 rem without being damaged; the figure of 60 rems has been agreed on. The trouble is that it is extremely difficult to be sure about radiation damage—a person may feel perfectly well, but the cells of his or her sex organs may be damaged, and this will not be discovered until the birth of deformed children or even grandchildren. Missions of the Apollo flights have had to cross belts of high radiation and, during the outward and return journeys, the Apollo crew accumulated a large amount of rems. So far, no dangerous amounts of radiation have been reported, but the Apollo missions have been quite short. We simply do not know yet how men are going to get on when they spend weeks and months. [br] It can be inferred from the passage that ______.

选项 A、the Apollo mission was very successful
B、protection from space radiation is no easy job
C、astronauts will have deformed children or grandchildren
D、radiation is not a threat to well-protected space explores

答案 B

解析细节推理题。根据文章第一段和第二段可知，宇航服和宇航船不能为宇航员阻挡住所有的辐射，并且可能导致他们第一代甚至第二代畸形。因此，B选项为正确答案。A项的内容并未在文中提到。根据文章第二段第四句可知，C项“宇航员的子孙都会畸形”是错误的。D项也与原文不符。

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