Inside the Sun Join Me. We’ll visit the home and laboratory of Dr. Z. Dr. Z began his solar studies when he was a little boy, while sun burning beside a swimming hole in his home town of Hannibal, MO. His vast knowledge of the sun is reflected in hundreds of theoretical papers and presentations. All this is eclipsed, however, by his ability to introduce students to the sun, without, as he puts it, getting sun-burned. Dr. Z lives in a geodesic dome perched on a mountain near Asheville, NC. An array of long and skinny, wide and short, round Telescopes protrude from the second floor windows and roof. The home looks suspiciously like a porcupine. His furniture is simple. The color scheme is bright and orderly like a painting by Piet Mondrian. The home is divided into four areas: living, sleeping, eating, and thinking quarters. A full-size print of Henri Matisse’s, “The Flight of Icarus,” hangs on one wall of his living room, and faces, on the other, a copy of Bruegel’s, “Landscape with the Fall of Icarus.” Dr. Z: Welcome, Me. It’s a pleasure to meet you. Me: Dr. Z. It’s my honor. Dr. Z: Would you like a glass of plasma before we talk? Me: They warned me that you play with words. Dr. Z: Ah ha! (tee-hee) Then you’ve come prepared. Words are slippery. I’ll use them to keep you on your toes. Please, have a seat on that fusion over there. Me: You mean the futon? Dr. Z: Why, naturally. Now, what can we do for you? Me: Tell me about the sun. Dr. Z: Everything? Or the short version? Me: The short version, I’m sure. I want my readers to learn and become curious at the same time Dr. Z: Excellent. Let’s see. To begin with, the sun’s a bully. Not because it wants to be. It simply can’t help itself. Me: Why a bully? Dr. Z: Excuse me a moment, it’s time for the solar weather report. Let’s listen. Radio Announcer: “….today’s solar weather is brought to you by Verizon, Verizon, meeting today’s telecommunications needs with tomorrow’s technology. And now the solar weather report for May (static). The Space Environment Center of the National Oceanic and Atmospheric Administration reports a solar wind speed of .05 kilometers per second, a dynamic pressure ranging from 1 to 5 en Pa’s, magnetic field B 2 components range between zero and minus 2 en tee’s. On our Website, http://www.sel.noaa.gov, telecommunications, electrical power plant engineers, and NASA personnel can view a large scale H-Alpha image of Region 9912 received……. Dr. Z: Did you understand that, Me? Me: Nope. Dr. Z: Honesty, too. Solar weather reports are a lot like mental pretzels. People listen. Their minds twist in confusion, like solar magnetic fields bubbling up through the sun’s photosphere. Me: Magnetic fields? Thank heavens. Something I recognize. Are they important? Dr. Z: Exceptionally. Close your eyes and imagine the sun. Looking at it hurts the eyes. Let’s imagine together. Me: Okay. If you say so. Isn’t this weird science, though? Dr. Z: Not at all! Imagining illuminates. (tee hee) First, we’ll fly our imaginations to Scotland and join the Bard. Me: You mean Shakespeare? I haven’t read Shakespeare in so long. Please keep this simple. Dr. Z: Roger! Imagine the cauldron of the three witches in the Scottish play. That’s the sun. Me: Are you superstitious? That’s the play Macbeth. There was a fourth witch, Hecate. Dr. Z: Ah, a well-read lady. Me: (blushing) Well, thank you. English major, but please continue. How is the sun like the cauldron? Dr. Z: Because it boils and bubbles and it’s full of toils and troubles. (Tee-Hee). Me: But the three witches are evil and superstition and forecast the future. What does that have to do with the sun? Dr. Z: Nothing. (tee hee) But, when I read that infernal play, I couldn’t understand what they threw in the cauldron. That is just like the sun. There is a lot about the sun’s cauldron, we can’t explain. The witches, though, I can tell you what they are. Me: What? Dr. Z: The first witch is atomic matter, protons, electrons, super-heated masses of this stuff. What Scientists call Plasma. Me: What you offered me to drink? Dr: Z: Words are slippery things, aren’t they? Between us, I prefer plasma to Tabasco sauce. It’s hotter. (tee hee) The second witch is the electromagnetic spectrum, a wild-eyed, witchy-mix of rays, or photons, everything from radio waves to gamma rays. The third witch, you’ll recognize her, she’s magnetism. Me: Wait, you forgot Hecate? Dr. Z: Ah ha! You’re still with me. Hecate, the boss witch, is energy--heat, magnetic forces, and the electromagnetic spectrum all mixed together. Me: This mix sounds evil. Dr. Z: An unwittingly, evil, bully. Are hydrogen bombs evil? Every second …Whoa…Quick. Look at your watch! When I say, “go,” tell me when one second is up! GO! Me: STOP. Dr. Z: Wow, did you feel that? Me: No, What. Dr. Z: In that one second, in the core, at the center of the interior domain of the sun, 700 million tons of hydrogen, heated to 15,000,000 degrees Kelvin, fused together and became 695 million tons of helium. Me: That doesn’t add-up, Dr. X. 700 million tons doesn’t equal 695 million tons. Dr. Z: Again, you’re listening. The extra 5 million tons became pure energy in the form of gamma rays. Bang! Whiz! Do you have any idea how big a bomb that is? That happens every second. Me: Nope. Dr. Z: Nope, what? Me: Nope, I don’t know how big a bomb that is. Dr. Z: Try the math. Start with the speed of light and multiply it by itself. That’s 299,792,458 meters per second times 299,792,458 meters per second. Got it?………. Me: hmmmmmmmm..hmmmmm. (Doing calculations in head) Dr. Z: Stop. Make it simple. Use scientific notation. Try 3x108 km/s. Now square it. Me: 3x1016 km/s. Dr. Z: Fantastic. The sun’s big numbers really beat up people. I’ll use as few as possible. Me: Thank you. Dr. Z: You’re welcome. Now multiply 9x1016 km/s times 5 tons of the mass of 4H, that’s hydrogen, times .007. Me: You’re kidding. Dr. Z: Yes (tee hee). Me: But I recognize it. Dr. Z: What? Me: The formula. That’s E=mc2. Dr. Z: Why didn’t I say that? Me: You want me to think? Dr. Z: It helps. The sun is an evil bully if we mess with its power, don’t think, and act irresponsibly. It’s evil if we stare at it—it will blind you. I’m not kidding. It’s really evil on the back of a little boy reading a book in Hamilton, MO. Me: Is that why you study the sun, to discover why it can be evil? Dr. Z: And to find the good—like petunias do. No, I don’t have a big enough magnet. Only a magnetic container can contain the power of the sun. Keep imagining, it’s the only way to get at the sun’s “geography” and tie the three, I mean four, witches together in our minds. Me: I’ve got my mental magnetic attraction gathering your solar filings. Dr. Z: (tee hee) You’re catching on. The best understanders of the sun’s mysteries have a real shine for whimsy. Let’s go. Me: Where? Dr. Z: We’ve been in the core. That’s the center. That’s where that thermonuclear fusion, the big, hydrogen-bomb-per-second takes place. The energy comes out in gamma rays, gamma photons, actually, radioactive particles. Guess how long it takes one of these little gamma doohickeys to go 5.2 million kilometers from the sun’s core, up through the radiative layer, to the photosphere? Me: Well, it’s moving at the speed of light. The sun’s radius is 54.5 times the Earth’s diameter, so…… Dr. Z: Pshaw! You’ll fry your brain. The answer is 50 million years. Me: How come? It should take only 2 to 3 seconds. Gamma rays are like light aren’t they? So they must move at the speed of light. Dr. Z: They are and they do, except for the collisions! Trillions of collisions. As it travels from the core it collides and ionizes other atomic particles. Everytime this happens, our photons lose energy. When they arrive at the surface, they may be lowly x-rays, or ultraviolet rays, and lot’s of them, are the light we see, mere shadows of their former selves. Me: 50 million years? You mean the sun’s light is 50 million years old? Dr. Z: Older. Some is younger, too. Old light comes after passing through the radiative layer. Young light is generated in the next layer up, the convective layer. Me: Convective. Convection, right? Dr. Z: Right. The radiative layer insulates the core; keeps it hot; keeps the hydrogen protons banging and fusing and making helium atoms. The convective layer is boiling gases, Hydrogen and Helium mostly. The gas heats, rises, cools, and sinks in giant bubble-like patterns. It’s one of the sun’s dynamics that creates the writhing magnetic flux of the sun. The top edge of this layer is called the photosphere. “Photo,” get it? We can see it from the Earth. Through special telescopes orbiting in outer space, we watch the photosphere boiling. Heated masses of gas rise to the surface, expand, cool, and sink. Me: I know about magnetic fields! Hooray. Finally, that word again, that and the word “light,” come to think of it. But how do the magnetic fields get formed? Dr. Z: Don’t know. Me: What? You mean, now that I recognize something you don’t know? Dr. Z: Cool, eh? (tee hee) Me: I’m disappointed. Dr. Z: Here’s what we know. We know that the sun is a mass of writhing magnetic fields. It’s also very low pressure, like the air pressure about 90 km. above the Earth— and that’s always a surprise to everyone. We believe magnetic fields are created by the up and down flow of the super-boiling gases rising and sinking, heating and cooling in the convective layer. We know that the whole sun has a magnetic field with poles just like the Earth, but there is no iron in the sun’s core. That was puzzling for many years. And we know that the poles of the sun rotate more slowly than the equator. This variable speed of rotation is really important in the formation of solar magnetic fluxes. Can you imagine the tidal waves and earthquakes we’d have if the Earth’s poles rotated at a different speed than the equator? The Earth – a giant rubic’s cube? A suitable toy for the gods. (tee hee) The sun’s body’s different rates of rotation produce and tear magnetic fields at the same time. Sunspots are actually massive magnetic fields. One spot is like the positive pole on a magnet, the other, the negative. The field lines go between, in and around, and move across the sun’s face. All these magnetic fields writhe. Their lines intersect. This creates incredible magnetic violence and stress. The fields whip and twist, snap and break, and extend above the photosphere into the chromosphere, out into the inner corona, and all the way out into, what we call the outer corona. As the field lines go out, the holes in them emit massive amounts of radioactive particles and x-rays. These x-rays and some of the plasma – electrons and protons – along with massive amounts of Hydrogen and Helium molecules, are flung out and we call this stuff the solar wind. The solar wind is constantly bombarding the Earth. And…my I do get carried away, don’t I? You’ll love the names! Me: What names. Dr. Z: The names we call the various magnetic-field wheelings and dealings. Me: Tell me. Dr. Z: Teeny ones are spicules. (Tee hee) Me: Teeny? Dr. Z: Yes, they’re about the size of the Earth. Me: Oh, teeny. Yes, I see. Dr. Z: And then there are prominences, and flares. Some scientists call them all flares. And the really big explosions – hmmm, you know explosion doesn’t seem to capture the essence, hmmm…. Me: The really big ones? Dr. Z: Oh…..Yes, they’re called solar particle ejections. Kind of formal-sounding beside spicules, don’t you think? Me: Definitely. Dr. Z, tell me. How have scientists learned all this stuff? Dr. Z: Technology. We stir the witches’ brew with technology. Me: What technology exactly? Dr. Z: X-ray telescopes, magnetograms are pictures of the magnetic field regions of the sun, spectroscopes identify the electromagnetic emissions, spectroheliographs isolate the light from one spectral line so we can decipher what’s being burned in the sun’s fuel pile, so to speak. Me: This is all so new. Dr. Z: Well, I’m not so old, either. (tee hee) I remember my first lunar eclipse. She was a beauty! That’s when I first saw the sun’s chromosphere. Vast red flames of solar particles and heated plasma flowed along the magnetic lines arching above the sun’s surface. Before x-ray telescopes, we couldn’t study the inner corona, the layer just above the chromosphere. It’s invisible from Earth because the photosphere is brighter. And even though it’s farther from the sun’s center than the chromosphere, it is hotter. This is a significant mystery. I’d love to see it all from Space Station Alpha. But from space, and even now from Earth, we create synthetic eclipses by blanking out the sun with special disks in our telescopes. If we go high enough in the Earth’s atmosphere, we can watch the sun’s surface roil. Don’t you just love that word? “Roil.” Mmmmm, delicious. Me: How do we know when the Earth might be bombarded by a solar proton ejections? Dr. Z: What’s the quickest way to bake a potato? Me: A what? Dr. Z: A potato? Quick, tell me, valuable solar particles are headed our way. Me: In an oven? No, a microwave! Dr. Z: Exactly! I knew you could answer your own question. We measure the microwave output of the sun. Solar generated microwaves, when they really start cooking those potatoes over there on the window sill (tee hee), may be accurate indicators of solar activity. But we’re not sure. We don’t know. But baked potatoes are delicious during solar particle ejections. Me: That, sir… Dr. Z: Oh, and yes. The GOES satellites. Almost forgot them. They measure the ultraviolet light, most of which doesn’t get to the Earth, thank heavens, and other forms of solar radiation flowing from the sun. But we still don’t predict solar weather as well as the weathermen on Earth predict Earth weather. Want to know another professional secret? Me: Yes. Dr. Z: We’re sitting in the last layer of the sun, the sun’s outer corona. Me: What do you mean? Dr. Z: The sun’s outermost magnetic fields extend way past the Earth out into the Solar System. For all we know, a blast from the sun may just be a leap of electromagnetic and radioactive protons jumping from one magnetic field line to another, farther into space. Me: Why don’t we just burn up? Dr. Z: The Earth has protective devices of its own. That’s called Solar-Terrestrial Interactions. Me, I have a potato waiting for me. How do you feel? Light-headed? (tee hee) Me: Such a pleasure, Dr. I know much more about the sun. Dr. Z: I wish I did. Would you share it with me? (Tee Hee) As scientists, we know some things in general. But explaining all of the con-fusion (tee hee) and electromagnetic e-missions and magnetic processes and interactions of energies, our four Macbethian witches, is truly beyond our present abilities. E= mc2 is a mathematical model that explains some of the phenomena of the Earth and sun. But creating a model for the electromagnetic dynamics of the Sun is truly a new frontier. Me: Why do scientists even try? Dr. Z: In my case? Me: Yes? Dr. Z: Sunstroke (tee hee). Me: Dr. Z, you’ve been wonderful. Thank you. Dr. Z: No, thank you. The fusion you are sitting on needed some breaking in. (tee hee) Me: Goodbye, Dr. Dr. Z: Goodbye, Me. Don’t let the sun hit your eye like a big pizza pie. You know what that is? Me: No, a song isn’t it? Dr. Z: That’s amore. Me: I thought you would be blind if the sun hits your eye for any length of time. Dr. Z: The poet’s say that love is blind. Eh? (tee hee) Goodbye, Me, and good luck.