题目
Gliese 581g is the sixth planet to be found circling a dwarf star some 20 light-years away, in the constellation of Libra. On paperit looks good – three times the mass of the Earth with possibly a rocky surface and enough gravity to hold on to an atmosphere.
The researchers also promised shirt-sleeve weatherin some regions, but not everywhere. One side of the planet is almost always in sunshine; the other almost always in darkness and estimated temperatures range from minus four degrees Celsius to a very hot 71 degrees. A year meanwhile would go by in just 37 days.
Of course, whether life could really be supported on Gliese 581g will need much more investigation and, most probably, technologies which don't exist yet. But the astronomers say planet hunting is getting easier and they were surprised how quickly they detected the tell-tale signsof this distant body, using ground-based telescopes.
21. Which of the following is correct about Gliese 581g？_____
A. It is a dwarf star with gravity.
B. It is a planet like the earth.
C. It was discovered many centuries ago.
D. It is very close to the earth.
22. What does Gliese 581g look like？_________
A. It has the mass of the sun.
B. It has about the same mass as the earth and its atmosphere.
C. Its rock and atmosphere are about three times the mass of the earth.
D. It is heavier than the earth and has a rocky surface.
23. Which of the following is correct about the gravity of Gliese 581g？________
A. It fixes the mass on.
B. It is too small to keep anything on the ground.
C. It is enough to hold on to an atmosphere.
D. It helps Gliese 581g to balance between the earth and the sun.
24. What does shirt-sleeve weather probably mean？______
A. So warm that a jacket is not needed.
B. Changeable.
C. Cold.
D. Extremely cold.
25. How was Gliese 581g found？__________
A. A scientist discovered it on the way to the moon.
B. Some scientists found it with a telescope on the shuttle.
C. It was found using telescopes on the earth.
D. It was found with the help of a computer.
更多“Gliese 581g is the sixth planet to be found circling a dwarf star some 20 light－years away”相关的问题
第4题
A．P(S)、V(S)和V(S)
B．P(S)、P(S)和V(S)
C．V(S)、P(S)和P(S)
D．V(S)、V(S)和P(S)
第5题
已知系统结构图所示，求传递函数C1(s)/R1(s)，C1(s)/R2(s)，C2(s)/R1(s)，C2(s)/R2(s)。
第6题
A.LASTVT(S)={ +，a，) }
B.LASTVT(S)={ +，a }
C.LASTVT(S)={ +，) }
D.LASTVT(S)={ a，) }
相关内容
警告：系统检测到您的账号存在安全风险
为了保护您的账号安全，请在“赏学吧”公众号进行验证，点击“官网服务”-“账号验证”后输入验证码“”完成验证，验证成功后方可继续查看答案！
