2. 考研
  3. The U. S. space agency, NASA, is planning to launch a satellite that scientists hope will answer fundamental questions about the

The U. S. space agency, NASA, is planning to launch a satellite that scientists hope will answer fundamental questions about the

admin2020-03-31  76
问题     The U. S. space agency, NASA, is planning to launch a satellite that scientists hope will answer fundamental questions about the origin and destiny of our universe. (1)______
    The prevailing theory of the universe’s origin, the "Big Bang" theory, says all matter and energy were once compressed into a tiny point. The density and resulting temperature were so enormous that, about 13-to-15-billion years ago by current estimates, a mighty explosion flung the matter hurtling outward in all directions. (2) ______They also ask, is the expansion accelerating? Will the universe collapse? What is its shape? Scientists will seek explanations with NASA’s new Microwave Anisotropy Probe, abbreviated as MAP. (3)______
    "MAP will take the ultimate baby picture, an image of the infant universe taken in the fossil light that is still present from the Big Bang, " he says. "This glow, this radiation, is the oldest light in the universe. Imprinted on this background, physicists knew, would be the secrets of the Big Bang itself. "
    This background radiation is the light and heat that the early cosmic soup of matter emitted. Once roiling hot, it has cooled over the eons to just a few degrees above absolute zero. It was once thought to be distributed evenly. But in 1992, a highly sensitive NASA satellite named COBE detected nearly imperceptible variations in temperature as tiny as 30-millionths of a degree.
     (4)______"These patterns result from tiny concentrations that were in the very early universe that were the seeds that grew to become the stars and the galaxies that we see today, " he says. "The tiny patterns in the light hold the keys for understanding the history, the content, the shape, and the ultimate fate of our universe."
     (5)______Princeton University scientist David Spergel says MAP will give us a much more accurate matter count than we have now. "Right now, we want to measure something like the matter-density of the universe, " he says. "Today, we can estimate that to a factor of two. That’s pretty good. What we want to do is be able to measure it to about the three-percent level, which is what MAP will be capable of doing."
    To do its job, the $ 145 million MAP spacecraft will settle into an orbit 1.5 million kilometers from the Earth. This is where the Earth’s and sun’s gravitational pull are equal, and well past the range of the Earth’s own obscuring microwave radiation.
    While the older COBE satellite measured just a small part of the sky, Charles Bennett says MAP will scan the entire sky at 1, 000 times better resolution. "The patterns that MAP measures are extremely difficult to measure, " he says. "MAP will be measuring millionths of a degree temperature accuracies, and that’s hard to do. That’s like measuring the difference between two cups of sand to the accuracy of a single grain of sand. "
[A] The principal NASA scientist for the new MAP spacecraft, Charles Bennett, says the heat patterns represent slight differences in the density of the young universe, where denser regions evolved into the present web of structures.
[B] NASA says the first results from the MAP mission will be ready in about 18 months after launch.
[C] The spacecraft will orbit the Earth seeking answers from an extremely faint glow of microwaves that have existed since the beginning of time.
[D] Scientists are trying to learn how it clumped together to produce stars, clusters of stars called galaxies, and clusters of galaxies.
[E] Astronomers are reporting evidence that points to a massive star-eating black hole at the center of our Milky Way galaxy.
[F] One of those keys is the amount of matter and its density. More matter with a higher density means more gravitational pull, suggesting a slowing of the universe’s expansion, and perhaps even its collapse.
[G] The head of NASA’s Evolution of the Universe program, Alan Bunner, says MAP will measure what is thought a remnant of the Big Bang—an afterglow of microwaves bathing the universe that was emitted by the ancient cosmic matter.
选项
答案D
解析 本题的空白处位于文章的第二段，这一段讲述了有关宇宙起源的“大爆炸”理论，即在宇宙之始，所有的物质和能量都聚合在一起，在130～150亿年前，逐渐增加的密度和温度导致了一场大爆炸，使得所有的物质朝着不同的方向飞散而去。空白处之后的一句：“They also ask…”中的“also”暗示前句提到的应该也是一个疑问。D项“Scientists are trying to learn how it…”正是科学家的疑问。另外“scientists”也正与“They”相呼应，由此可以推断D项“科学家们试图了解这些物质是如何聚集在一起形成星辰、星系和星河的”正确。
转载请注明原文地址:https://kaotiyun.com/show/KE1Z777K
0

考研英语一

相关试题推荐
随机试题
最新回复(0)