TRACK 93 TRANSCRIPT
Listen to part of a lecture in an astronomy class.
I’ll tell you a story about how one astronomy problem was solved. It happened many years ago, but you’ll see that it’s interesting and still relevant. Two, three hundred years ago, astronomers already had telescopes, but they were not as powerful as those we have now. Let’s say … they were at the level of telescopes amateur astronomers use today. Tell me, what do you see in the night sky when you use a telescope like that? Quick, tell me.
Even … like … the moons of Jupiter?
OK .. . what else? … You think that’s all? … Ever heard of nebulae? … I bet you have … Well, let’s just, um, put it up anyway …
Nebulae are small fuzzy patches you see in the sky, they look like little clouds. Many of them have a spiral shape, and that’s why we called them spiral nebulae … So astronomers in the eighteenth century … eighteenth century… when they looked through the telescope, they could see planets-and they knew those were planets … the moons of Jupiter—and they knew they were the moons of Jupiter… and then they saw spiral nebulae and they didn t have a clue.
What could those be? So, some of them thought—”these things are cloudy and fuzzy, so they’re probably small clouds of cosmic dust, and they don’t have to be very far away from us.” But there were others who thought, “OK, the things look small and fuzzy, but maybe they’re actually distant galaxies of stars, but we can’t see the stars, because they’re so far away and they seem so tiny that they look like dust, and even the whole galaxy looks like a tiny little cloud.”
Which of the two theories do you think was more…uh, surprising?
The galaxy one.
Well I mean it assumed that the nebulae are not what they look like at first sight. The first theory assumed that, right?
- And now tell me this … which one would have seemed more likely at the time?
Uh … They couldn’t tell.
Right. Two morals here: first, there can be different explenations for the same observation. And second, “obvious’ doesn’t necessarily mean “right”…What happened next was… for a long time nothing. More than 150 years. No one could decide… Both hypotheses seemed plausible … And a lot was at stake-because if the galaxy theory was right, it would be proof that the universe is enormous… and if the dust theory was right…maybe not so enormous. So the size of the universe was at stake… Finally in the 1920s we came up with a telescope that was strong enouqh to tell us something new here. When we used it to look at the spiral nebulae we saw…well, we were not absolutely sure … but it really looked like there were stars in those nebulae. So not dust after all, but stars …
But how far away were they, really? How would you measure that? Any ideas? Laura?
Well, how about measuring how strong those stars shine? Because, if the star Is far away, then its light would be weak, right?
Yes .. but there’s a problem here. You need to know how bright the star is in the first place because some stars are naturally much brighter than others. So, if you see a star that s weak … it can mean one of two things …
Oh … it’s either far away or it’s just a weak star.
And you can’t really always tell which. But you’re on the right track. There is a kind of star where you can calculate its natural brightness . .. and—you guessed it—we found some in the nebulae. It’s called a variable star—or a “variable” for short— because its brightness varies in regular intervals. I won’t go into detail here, but.. . basically … the longer the interval, the brighter the star, so from the length of those intervals we were able to calculate their natural brightness. This told us how distant they were—and many turned out to be very, very far away. So we can be sure that the spiral nebulae really are very distant galaxies—which is what some eighteenth– century astronomers guessed but didn’t have the instruments to prove …
Now, one reason I told you this story is that today there are still plenty of situations when we see something out there, but we really aren’t sure what it is. An example of one such mysterious observation would be gamma-ray bursters.
We’ve known about these gamma-ray bursters for a long time now, but we can’t all agree on what they are.
TRACK 95 TRANSCRIPT
Listen to part of a lecture in an art history class.
Today we’re going to talk about how to look at a piece of art, how to “read” it—what you should look for… what aspects of it you should evaluate. A lot of people think that if you stand in front of a work of art and gaze at it for a couple of minutes you’re evaluating it. But truly reading a piece of art, evaluating it properly, is a complex process, a process that takes time.
When we’re confronted with a piece of art, there’re several things we have to keep in mind, for example, its beauty … that’s where aesthetics comes in.
Aesthetics is the philosophy that deals with the definition of beauty, which goes all the way back to ancient Greece. They, um, the early Greek philosophers said that beauty and art are based on imitation. Their feeling about art was that it s beautiful when it imitates life; they thought that the truthfulness of an image, how truthful it is to life, determines its value as art. Today we have a broader definition of aesthetics.
Now don’t identify aesthetics as personal taste. Taste is bound by time; taste is tied to a society, a given set of moral values, usually. You may not like a piece of art from a different culture—it may not be your taste—but you appreciate its beauty cause you recognize certain aesthetic principles. Art generally adheres to certain aesthetic principles like balance, uh, balanced proportions, contrast, movement, or rhythm.
We’ll discuss aesthetics more in detail when we look at some pieces of art together. Another thing to keep in mind in evaluating art is that art has a purpose, generally determined by the artist. You may not know what it is, and you don t need to know what it is to appreciate a piece of art, but it helps. For example, if you know what the artist’s purpose is … if you know that a piece of art expresses the artist’s feeling about a political or social situation, you’ll probably look at it differently.
Now, besides beauty and purpose, what are the other aspects of a piece of art that need to be evaluated? Very simple-you examine a piece of art following these four formal steps. The first step is description . .. describe physical characteristics of the piece—like this painting is large, it’s oil on canvas. Describe the subject—it’s a person it’s a landscape—or predominant colors like, um, earth colors … that’s a description.
OK? So, you’ve described the piece. The next step is analysis. You’re looking at the piece for any universal symbols, characters, or themes it might contain. Certain symbols are universal, and the artist counts on your understanding of symbols. Even colors have symbolic significance, as you may know. And also objects depicted in a piece of art are often used to represent an abstract idea. Like wheels or spheres—they look like circles, right?—so wheels and spheres represent wholeness and continuity. I have a handout, a list of these symbols and images and their interpretations, that I’ll give you later. But for now, the point is that after you describe the piece of art, you analyze its content… you determine whether it contains elements that the artist is using to try to convey a certain meaning.
If it does, the next step is interpretation. Interpretation follows analysis very closely. You try to interpret the meaning of the symbols you identified in the piece. Almost all art has an obvious and an implied meaning. The implied meaning is hidden in the symbolic system expressed in the piece of art. What we see depicted is one scene, but there can be several levels of meaning. Your interpretation of these symbols makes clear what the artist is trying to tell us.
The last step is judgment or opinion—what do you think of the piece, is it powerful or boring?— but I give that hardly any weight. If the four steps were to be divided up into a chart, then description, analysis, and interpretation would take up 99 percent. Your opinion is not important in understanding a piece of art. It’s nice to say: I like it… I wouldn’t mind hanging it over my couch, but to evaluate a piece of art, it’s not critical.
- Now you know what I mean by “reading” a piece of art, and what it entails. Try to keep all that in mind next time you go to an art museum. I can tell you right now that you probably won’t be able to look at more than 12 pieces of art during that visit.
OK, now let’s look at a slide of a piece of art and try to “read” it together.
TRACK 96 TRANSCRIPT
What does the professor imply when he says this:
Try to keep all that in mind next time you go to an art museum. I can tell you right now that you probably won’t be able to look at more than 12 pieces of art during that visit.