2020/ 02/ 15 &16 聽力預測
Narrator: Listen to part of a lecture in an astronomy class.
Professor: Okay, we’re going to be looking through a number of star catalogues throughout this course because they’re important tools for astronomers. A star catalogue is a list of information about stars, information like its position in the sky, of course, and magnitude, which is its brightness. From historical perspectives, star catalogues are interesting because they tell us how much past astronomers knew and what they saw. One of the first star catalogues was produced by the Greek astronomer Hipparchus. This was around 129 BCE. That was an amazing accomplishment at the time and incredibly influential. Unfortunately, the Hipparchus star catalogue was lost along with most of his other writings. But we still know something about him. Hipparchus, if you still remember from our other discussions, was credited with a number of other important discoveries including precession of the equinoxes. Now, if you remember what precession is, yes, Jane?
Jane: It’s the idea that the stars shift positions in the sky over thousands of years.
Professor: As you’d commerce, yes. Why?
Jane: Because the Earth doesn’t rotate perfectly. It wobbles a little, right?
Professor: Yeah, because the Earth wobbles on its axis. Over time, the stars appear to move across the sky in relation to some fixed point. For instance, Polaris, what we call the North Star, is just above the North Pole now, but it will appear further and further away from it over time. It will, however, be back to the same position when the cycle completes in twenty-six thousand years. So, it was quite a discovery considering what Hipparchus had available to him. Anyway, precession of the equinoxes is important because using calculations based on precession, we can determine the position of the stars for any given date in history, but as I’ve said, we thought Hipparchus star catalogue was lost. Well now, it appears that the catalogue may be represented on the globe on an ancient Roman statue called Farnese Atlas, which is a copy of an even older Greek statue.
In ancient Greek mythology, atlas is the God that holds up the world, right? Well, the globe that Atlas is holding up here shows the ancient Greek constellation. Not the individual stars, but the figures they represent like Aries the ram and Hercules the hero. Anyway, the big news now is that well, some researchers have concluded that the original sculptor may have use Hipparchus’ star catalogue as a source of information in creating the sculpture. How did they figure this out? Well, we know the position of the stars where they are in the sky today, right? Well, by mentioning star positions on this globe, and then making calculations based on the precession of the equinoxes…
Male: Wait, wasn’t that Hipparchus’ discovery? You know, precession?
TOEFL Prediction 托福考前題目預測2021 (3)
