Space is a dangerous place, not only because of meteors (流星) but also becaus

游客2025-03-19 19

问题 Space is a dangerous place, not only because of meteors (流星) 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 spacesuits 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 (畸形的) 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 outside the protection of the atmosphere, working in a space laboratory. Drugs might help to decrease the damage done by radiation, but no really effective ones have been found so far. [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 explorers

答案 B

解析本题是一道暗示推断题。问从文章中我们可以推断出什么。通读全文，我们知道作者主要在讲述太阳和其他星体的辐射会给人体带来伤害，但是辐射对人体的伤害程度很难确定，需要很长的时间才能显现出来，从而可以推断出防止受到辐射的伤害不是一件轻而易举的事情。因此，本题的正确答案应是B。

转载请注明原文地址:http://tihaiku.com/zcyy/4003143.html

相关试题推荐

随机试题

最新回复(0)

Space is a dangerous place, not only because of meteors (流星) but also becaus

Humanbeingsactinadifferentwayfromthatofanimalsjustbecausetheyc

Humanbeingsactinadifferentwayfromthatofanimalsjustbecausetheyc