【正文】 the shape of sunspots, well, the sunspots weren’t circular. If they were shadows of the planets, they would be circular, right? So that was a problem for the prevailing view. And he also noticed that the shape of the sunspots changed as they seemed to move across the Sun’s surface. Maybe a particular sunspot was sort of square, then later it would bee more lopsided, then later something else. So there is another problem with the shadow hypothesis, because the shape of a planet doesn’t change. What Galileo proposed was that sunspots were indeed a feature of the Sun, but he didn’t know what kind of feature. He proposed that they might be clouds in the atmosphere, the solar atmosphere, especially because they seemed to change shape and there was no predicting the changes, at least nothing Galileo could figure out. That random shape changing would be consistent with the spots being clouds. Over the next couple hundred years, a lot of hypotheses were tossed around. The spots were mountains or holes in the solar atmosphere through which the dark surface of the Sun could be seen. Then in 1843, an astronomer named Heinrich Schwabe, made an interesting claim. Schwabe had been watching the Sun every day that it was visible for 17 years, looking for evidence of a new planet. And he started keeping tracks of sunspots, mapping them, so he wouldn’t confuse them with any potential new planet. （9）In the end, there was no planet, but there was evidence that the number of sunspots increased and decreased in a pattern, a pattern that began repeating after 10 years, and that was a huge breakthrough. Another astronomer named Wolf kept track of the Sun for an even longer period, 40 years actually. （10）So Wolf did 40 years of research, and Schwabe did 17 years of research. I think there is a lesson there. Anyway, Wolf went though all records from various observatories in Europe and put together a history of sunspot observations going back about 100 years. From this information, he was able to confirm the existence of a pattern, a repeating cycle. But Wolf detected an 11year cycles not a 10year circle. 11year cycles? Dose that sound familiar to anyone? No? Well, geomagnetic activity, the natural variations in Earth’s magnetic field, it fluctuates in 11year cycles. Well, we’ll cover this later in this semester, but for now, well, scientists in the late 19th century were aware of geomagnetic cycles, so when they heard that the sunspots’ cycle was also 11 years, well, they just had to find out what was going on. （11） Suddenly, everyone was doing studies of the possible relationship between the Sun and the Earth. Did the sunspots cause the geomagnetic fields or did the geomagnetic fields cause the sunspots? Or is there some other thing that caused both? And astronomers did eventually figure out what sunspots had to do with magnetic fields. Actually they are magnetic fields. And the fact that sunspots are magnetic fields accounts for their dark appearance. That’s because magnetic fields reduce the pressure exerted on the gases inside of them, making the spots cooler than the rest of the Sun’s surface. And since they are cooler, they are darker.詞匯：sunspots n. 太陽黑子heavenly body 天體flaw n. 缺陷；裂縫blemish n. 瑕疵；缺點hypothesis n. 假設prevailing adj. 流行的；盛行的square n. 正方形lopsided adj. 不平衡的feature n. 特色；特征random adj. 隨機的；任意的toss v. 投擲visible adj. 明顯的；看得見的keep tracks of 記錄；與保持聯(lián)系map v. 繪制地圖geomagnetic adj. 地磁的fluctuate v. 波動；漲落題目：6. What is the lecture mainly about?解析：主旨題，文章按照時間順序介紹，主要講人們對太陽黑子的科學認知的進程。復聽部分教授說目前沒有適合這個學生的，建議他等到下學期。所以做這個工作的人需要愿意接受不規(guī)則的工作時間。答案：To take advantage of an academic program3. Why does the student mention hosting foreignexchange students?解析：意圖推測題，定位host foreignexchange students，學生說通過這個項目他發(fā)現(xiàn)自己喜歡跟不同的人接觸，通過原文中教授說“這使你來我們這個項目”看出他是在解釋為什么喜歡這個項目。學生說東北部沒有他喜歡的專業(yè)——國際學，只有Central University有。TPO18 Conversation 1（場景分類——詢問工作）Narrow: Listen to a conversation between a student and an administrator in the university employment office.Student：Hi! I hope you can help me. I just transferred from Northeastern State University near Chicago.Administrator：Well wele to Central University. But Chicago is such a great city. Why did you leave?Student：（2）Everyone asks that. It’s my hometown. And it was sure convenient to go to a school nearby. But Northeastern is still fairly small. And it doesn’t have the program I’m interested in. I want to major in international studies. And the only program in the State is here.Administrator：We do have a great program. Well how did you get interested in international studies?Student：（3）My family hosted a few foreign exchange students while I was growing up. Then I took part in an international summer program after I graduated from high school. I thought I really I like meeting people from all over, getting to know them.Administrator：OH! Ok! And that led you to our program. （1）Right now though I think you are looking for a job.Student：Yeah, a part time job on campus. I thought I’d save money, being away from the big city. But it doesn’t seem to be working that way .Anyway I’m not having much luck.Administrator：I’m not surprised. Most of our campus jobs are taken in the first week or two of the semester. What work experience have you had?Student：Well, I worked in the university library last year. But I already checked at the library here. They said their remaining positions were for workstudy students getting financial aid. I’ve never run into that before.Administrator：Well, I guess each school has its own policies. （5）Uh, we really don’t have much right now. You might be better waiting until next semester. If you really want something, how are your puter skills?Student：About average I’d say. I helped teach some of the basic puter classes. Northeastern offers for new users, if that helps any？Administrator：OK, the technology support department needs people to work its helpdesk. It’s basically a customer servic