토플 리딩 문제 한번 풀어보세요
1. Question
The Nature Of Astronomy
Astronomy is defined as the study of the objects that lie beyond our planet Earth and the processes by which these objects interact with one another. We will see, though, that it is much more. It is also humanity’s attempt to organize what we learn into a clear history of the universe, from the instant of its birth in the Big Bang to the present Moment.
In considering the history of the universe, we will see again and again that the cosmos evolves; it changes in profound ways over long periods of time. For example, the universe made the carbon, the calcium, and the oxygen necessary to construct something as interesting and complicated as you. Today, many billions of years later, the universe has evolved into a more hospitable place for life. Tracing the evolutionary processes that continue to shape the universe is one of the most important (and satisfying) parts of modern astronomy.
Q. Why does the author say “For example, the universe made the carbon, the calcium, and the oxygen necessary to construct something as interesting and complicated as you”?
a. To explain one way in which the universe has evolved significantly over great lengths of time
b. To explain why the universe evolves so much over long periods of time
c. To describe one topic of study in the field of astronomy
d. To prove how quickly the universe evolves
2. Question
Europa, a Moon with an Ocean
Europa and the inner two Galilean moons, are not icy worlds like most of the moons of the outer planets. With densities and sizes similar to our Moon, they appear to be predominantly rocky objects.
The most probable cause is Jupiter itself, which was hot enough to radiate a great deal of infrared energy during the first few million years after its formation. This infrared radiation would have heated the disk of material near the planet that would eventually coalesce into the closer moons.
Thus, any ice near Jupiter was vaporized, leaving Europa with compositions similar to planets in the inner solar system.
Despite its mainly rocky composition, Europa has an ice-covered surface, as astronomers have long known from examining spectra of sunlight reflected from it. In this it resembles Earth, which has a layer of water on its surface, but in Europa’s case the water is capped by a thick crust of ice. There are very few impact craters in this ice, indicating that the surface of Europa is in a continual state of geological self-renewal. Judging from crater counts, the surface must be no more than a few million years old, and perhaps substantially less. In terms of its ability to erase impact craters, Europa is more geologically active than Earth.
When we look at close-up photos of Europa, we see a strange, complicated surface. For the most part, the icy crust is extremely smooth, but it is crisscrossed with cracks and low ridges that often stretch for thousands of kilometers. Some of these long lines are single, but most are double or multiple, looking rather like the remnants of a colossal freeway system.
Q. In paragraph 5, the author mentions “close-up photos of Europa” in order to:
a. Identify its location in the cosmos
b. Explain why Europa is not an icy world like most of the moons of the outer planets
c. Show proof that Europa is different from other planets
d. Explain how astronomers know what Europa looks like