Donald: Welcome to NASA-Ames Research Center in the heart of Silicon Valley. And welcome to this year's Sun-Earth Connection celebration, celebrating the equinox. My name is Donald James and I'm the education director at NASA-Ames, and I'm joined here in the auditorium by students and teachers from schools in Oakland, San Jose, and Foster City.

During this program, we will recognize Sun-Earth Day as a celebration of the Sun, the space around the Earth and how the Sun affects our life on our planet. NASA-Ames is producing this broadcast together with the Goddard Space Flight Center in Greenbelt, Maryland, and the Stanford Solar Center at Stanford University.

During this live program, students and teachers at other NASA centers are celebrating with us. In addition, students across the country and around the world are watching this program live. And we welcome you.

More than 4,500 science teachers have been invited to education workshops related to the science of the Sun-Earth connection. Welcome to you all.

The Sun-Earth connection theme this year is "Celebrate the Equinox." Thank you for joining us as we place traditional star knowledge side by side with NASA knowledge of space science and astronomy and strive to better understand the universe we live in. Now, on with the show.

Donald: And now your host, the guy who put the sunshine in [inaudible], your friend and mine Paul [Mortfield].

Paul: Hi everybody, and welcome to Sun-Earth Day 2002 and helping us celebrate the equinox. I'm your host Paul Mortfield. I'm an astronomer at the Stanford Solar Center at Stanford University and I work with a group of scientists that are studying the sun using telescopes here on Earth or special telescopes and instruments on satellites up in space.

Now this year, we're doing things a little bit different. Last year's show was only a Web Cast. This year's show, we're putting it out on NASA TV so a lot more people can see the show and participate in the show.

Now for those of you that may have been keeping score about the equinox, well it starts today at 1:16 in the afternoon here on the West Coast, which means it's going to be at 4:16 in the afternoon for those of you on the East Coast.

Now one of the great things about doing a show like this, and especially since it's over the Web, is for those of you that are out there, you can ask questions over chat rooms and ask questions to us here, and we're going to try and get them answered by some of our guest experts. So maybe we can put up where the chat room URL is and for those of you that are watching.

Write this URL down and try and get to the chat room and ask some questions. We've got lots of time today, we've got lots of great guests, and hopefully we'll get some of your questions answered.

Now, in the studio today we have a whole bunch of students that are going to present some of the results from activities that they've done, and students around the country have done some of these same activities. So it'll be really great to try and compare results and see how everybody did.

Also with us, we have some special guests with us that are going to help answer some of the questions.

And with us today, we have some people here on stage representing the Lakota tribe.

We have Nathan Chasing Horse. Nathan, welcome to the show.

And we also have some solar scientists with us as well.

We have Dr. Aimee Norton from the National Center for Atmospheric Research in Boulder, CO.

Welcome Aimee. Aimee was with us last year.

So she's an old pro at showing up to these shows.

As well, sitting beside here is Dr. Marc DeRosa.

From the Lockheed Martin Solar and Astrophysics Lab locally here in Palo Alto, CA. Marc, welcome to the show. This is your first time here.

And also with us, the person you're going to here his voice throwing the questions out to all of us during the show is another solar scientists, Dr. John Beck

sitting down in front here with us. He's with the Solar Oscillations Investigation Team at Stanford University, again, right around the corner.

So we've got some great scientists and guests with us today.

Another thing we have during the show as well is we're going to see a little bit of a video.

We were trying to get an astronaut to come here to answer some questions, but unfortunately, he couldn't make it so I had to go there and ask him all these questions. I took some of your questions and asked him. We're going to run a little bit of that video later.

Another great thing we have with the show today, there's a group of students throughout parts of North America that are operating solar telescopes for us today. And just so we know who they are, there's a group of students from the Elliot Middle School in Pasadena, CA, that are operating a telescope up at Mt. Wilson.

And we have a group of students from the Universidad de Sonora at Hermosillo in Mexico that are operating another solar telescope. And on the East Coast, we have students from the Thomas Jefferson High School, operating a telescope at the Howard University Astronomical Observatory.

And throughout the show, we're going to be flipping to some live shots of the sun that will either be coming from those telescopes or even some of the spacecraft we have up there in space.

So another thing we're also going to do here during the show and I'm going to get started with that is I want to take a little bit of time throughout the show getting to know some of the guests that we've brought on here. So this way, you get to know a little bit more about them, who they are, what they do, and how they wound up here and what they wind up doing.

So to get started with that, we're going to talk to Dr. Aimee Norton. And Aimee, tell us a little bit about, we've got some time here. Oh, you need the microphone. That'll help. Tell us a little bit about what do you do?

Aimee: Well, I study the Sun and I'm actually interested in looking at, I'm looking for magnetic waves on the solar surface. So, I use data taken from telescopes on the ground, on the Earth, one in New Mexico, and I also use data taken from a spacecraft called SOHO which you might have heard about. And I spend my days looking at the data and looking for these magnetic waves.

Paul: Very cool. So what is so exciting about your job?

Aimee: Well, there's secrets that only the Sun knows and you can maybe find them and [graphs] if you look hard enough. So that's exciting.

Paul: So, you wind up going through the graph looking for data and stuff?

Aimee: I'm looking for secrets in the curve that you see on your graphs on the screen. And it's also exciting to think about the ways that the Sun interacts with the Earth and know that we're a part of the system and see solar storms and all that stuff.

Paul: So here's a question for you. What made you choose this as a career?

Aimee: Well, I've always been interested in science. I actually started off in college doing engineering.

And the more I learned about pure physics and astronomy [in specific], I turned more towards that. And that's all.

Paul: What about any hobbies or other outside interests?

Aimee: Oh, I love science fiction. I read a lot of science fiction novels all the time. I like science-fiction movies. That's a hobby.

Paul: And you also had a unique experience that some of the students have been learning about with the equinox, north and south of the Equator. You've had an opportunity to live somewhere else on this planet.

Aimee: Right. I lived in Australia. My husband's Australian and we moved there and lived there for two years. And the southern hemisphere is very different from the northern hemisphere. There is a lot of differences.

So when you move around the planet, you can encounter differences.

Paul: So you're going to be an expert on what happens south of the Equator when some of the students come up here and talk about some of that.

Aimee: Great. If you have any questions south of the Equator, I'm the one for you.

Paul: Great. And also, don't forget that we have the chat room open, so if you've got questions out there, please send them in. And I was wondering, maybe we've got a question that we can start with?

John: We sure do, Paul. Actually, the chat room,

I'd just like to remind everyone to be sure and give your first name so we can identify who's asking the question. For example, our first question here, she says her name is Jeannie, she's 14 years old, in the 9th grade and she writes, "I happen to look over your Sun-Earth Day celebration, I saw the purpose somewhat is to show how the Sun affects all living things from human beings to animals and I have a question. Is it true that the Sun is often seen as a God or heavenly body?" It also has a follow-up question. "Is this day supposed to bring different cultures together to celebrate something that many have in common as an entity, and to understand its origin?"

Marc: I would say that the Sun for many past civilizations have definitely viewed the Sun as a God. And today, it's trying to be understood scientifically in that context.

So maybe Nathan can discuss a little bit more about what some of his culture views the Sun has.

Nathan: Well, the Sun to many nations on this Turtle Continent, this Turtle Island is we consider as holy. It's a sacred energy that makes everything grow and with the Sun, today, and the question of bringing cultures together and nationalities, I would say yes, because, and one of our symbols we call the [Chungwesh ka wakan] or the sacred, the circle of life in which the four winds meet. There are four sacred colors, representing the four colors of men; the black, the red, the yellow and the white, which I have on the back of my, here.

Also symbolizing unity and coming together. So it, I would say yes it does represent a spiritual entity, bringing us together.

Paul: Great. Down in front, we've brought down the first group of students here and we've got a bunch of charts. We have a chart here and who's going to be the one that's going to say some words about this? Who is the one who is going to start?

Ben's going to start? Okay. What do we have here?

Ben: We have a chart that shows hours of daylight in each season. The black line tells about how long the hours of daylight are and the colors are the seasons. Pink is for fall, yellow is for summer, green is for spring, and blue is for winter.

Paul: That is great. And this is for which location?

Ben: NASA-Ames.

Paul: Okay, so this chart here is for our location right here?

Ben: Yes.

Paul: Okay. Was there any other charts that we have? Or any other comments?

Ben: The days are longer in summer and spring each year and shorter in fall and winter.

Paul: Great, and that's for our location here?

Ben: Yeah.

Paul: And, go ahead. Where's Nicole. Hang on.

Nicole: Today has exactly 12 hours of sunlight.

Student: It's called Equinox.

Paul: Anybody else? Is there another group? Okay, so while this group, let's thank this group as they walk off. Now let's try and take a question from the chat room. See if we've got another question in here.

John: Okay, we have a nice question. Unfortunately, the person who asked this question didn't specify his or her name.

But they ask, why would an [aurora] appear in the Earth's magnetosphere?

Aimee: An aurora is actually caused by an energetic event on the solar surface.

And what happens is matter is spewed off of the solar surface and that matter comes and interacts with the Earth's atmosphere. And so an aurora is charged particles coming down the magnetic field lines of the Earth's atmosphere and ionizing things in the Earth's atmosphere and that energy causes the colors to show up in the Earth's atmosphere. So I hope that answers your question, whoever asked it on the chat room.

Paul: Okay and down here in front, we brought down another group of students here. And they've got another chart up, and who's going to explain to us what this chart is? Will you? Okay.

Student: This is a map of, showing the hours of daylight in Singapore and since it's mostly summer there, it's usually 12 hours, almost all the time. It's near the Equator.

So it's always really warm.

Paul: And what about the shortest or the longest day?

Student: The shortest day is 11 hours and 54 minutes and the longest day is 12 hours and 6 minutes.

Paul: So really what we're showing here, there isn't too much difference of a city that's basically on the Equator?

Student: No.

Paul: Does anybody else have anything to add to this? Great. Well, thank you. I think we're going to take another question from the chat room. Let's thank these guys here.

John: Okay, our next question from the chat room, again, the person didn't give the name. But they ask, "What is the strangest thing about our Sun?"

Marc?: I would say one of the strange things about the Sun that's definitely a subject of active scientific investigation now is how all the magnetic field that we see in the Sun is produced. For many years it's been known that the Sun has a sunspot cycle where the number of sunspots rises and falls every 11 years, but exactly why it's 11 years and how the sunspots form is a big mystery.

Paul: Okay, and if we switch back down here, we have another group of students who have come down. And they're going to show a different city and who's going to be the spokesperson for this one here?

Okay, Evan's going to say something.

Evan: In Melbourne, sunlight heats the Earth and even the more sun in Melbourne, the more heat there is and the longer days are warmer in Melbourne.

Paul: And where is Melbourne?

Evan: In Australia.

Paul: Which is south of the Equator?

Evan: Uh-hum.

Paul: Anything else to add on this? These are great charts. Well, thank you very much. And I think we're going to take another question from our chat room.

John: Okay we have a good one here and the person who asked the question, Mark, did specify his name and his age. I think this is a question Paul should take.

John: Mark asks, "Why do you celebrate Sun-Earth day and not Moon-Earth day?"

Paul: Why do we celebrate Sun-Earth day and not Moon-Earth day? Well, Sun-Earth day is because some of us are solar scientists and we study the Sun and not the Moon. But actually one of the important things to realize about studying the Sun and celebrating this whole Sun-Earth thing is the fact that we're really concerned about the effects the Sun has on Earth, on our own planet.

And for astronauts that are up in space traveling around, that's also very important, because we're pretty much protected down here on Earth. But up in space, the astronauts have to contend with problems from the Sun, solar flares, things we call CMEs, and for any of us and any of you out here who want to go up into space and maybe travel to Mars, that's going to be pretty important stuff to have to deal with.

So I think that's why we wind up celebrating and studying Sun-Earth. That's good. Someone was trying to throw me off here today.

Okay, we're actually going to fire off a video here, and this was kind of really exciting, because I didn't have a chance to get an astronaut to show up here live for our show, which would have really been great.

I took a bunch of questions from several students and went to Houston, Texas, to the Johnson Space Center to interview an astronaut. And this particular astronaut has walked on the Moon. He has flown the shuttle, he has also been on the Gemini two-man spacecraft, and he's been up in space six times.

And one of the things they said about him is the fact that he has launched seven times. How can that be, if he's been up six but has launched seven? Six times from Earth, and once from the Moon, that he got back up into space. So I think we have a video here to show and let's see if we can roll that.

Video: No NASA Webcast would be complete without an interview with an astronaut. So I took your questions and I've come down to the Johnson Space Center here in Houston, Texas to talk to a real astronaut who knows the answers to these questions.

So with me today is John Young, an Apollo 16 member. He's walked on the Moon, and John, welcome today, welcome to Sun-Earth day.

John Young: Thanks.

Paul: So we've compiled some questions from some of these students and they'd like to get some answers from a real astronaut who's been up there and who knows what goes on. So first off, I've got a question from Shayna, and she wanted to know how did you feel when you first took off and was shooting into space?

John Young: Well, they train you a lot to react to what happens.

So you're all trained to handle the [abort/aboard?] procedures of going up hill and getting into space. And so you're basically thinking about what's going to happen next.

So if you're trained properly, you don't think about anything but doing your job, which is monitoring the instruments, making sure they're working right, making sure your trajectory's pointing in the right direction when you shoot up hill and being ready to handle the next [abort] mode.

Paul: And since the show is dealing with the Equinox, Gina wanted to know does the sunrise look different from the space shuttle vs. what it looks like down here from Earth?

John Young: Well sunrises and sunsets around the Earth are just beautiful. You get one every 45 minutes if you fly around the Earth, a sunrise or sunset, and they're just gorgeous.

You know, we take a picture of sunrise and sunset just like you do on Earth and they never come out near as good as what you see with your eye.

You may have noticed your sunrises and sunsets on Earth, it's often the same way.

Paul: Another question is from Elaine and, if we knew then what we know now about solar flares, solar radiation, and the effects that they have out in space, would you still have walked on the Moon?

John Young: Why sure. The exploration of the Moon, that's really one of the most important things that we've done so far in human exploration of space. It's hard for me to believe that right now we don't have a big base up there with human beings exploring. The Moon is a fascinating place. We'll find when we get back up there that we don't understand it near as well as we think we do when we get human beings up there looking at all the surfaces and seeing what's there.

Paul: And Brandon wanted to know when you did go up there, did you get hazard pay?

John Young: No, NASA doesn't pay you hazard pay. The statistics for our missions, our Apollo 16 mission was the chance of being unsuccessful about 1 in 5. It was very high risk, but that's the way life was in those days. And we didn't think about such a thing.

Paul: As an astronomer, I have this really bad habit of every time I walk outside at night, whether it's going out to the movie theater or walking out of home or a restaurant, I'm always looking up in the sky to see the stars, to see what's up, maybe some planets. And usually certain nights I'll wind up seeing the moon. But for you, you had a very unique experience.

You were able to walk outside on the Moon and look up in the sky and from the image we have in the backdrop there, you got to see the Earth. And what was it like to look up in the sky and see the Earth hanging up there?

John Young: Well, on our mission, the Earth was straight overhead. So if you had looked up with your big backpack on, you would have fallen flat on your back. So we didn't get to see it.

On the Moon, because it's so bright up there in the daytime, your eyes are like pinpoints. So you look out and all you see is the blackness, you don't see any stars at all.

Now we had a telescope in the lunar module that we looked through to find the stars, because we had to align our inertial platform so we could perform correctly when we lifted off from the surface, which was very important. And we used that telescope to see the stars. And that worked fine.

Paul: That is so cool because one of the other questions that I had later on was could you see stars at all?

John Young: Could not see the stars. Not in the daytime, no. Now at night, they'd be beautiful.

Paul: And Ryan then wanted to ask, so what's it like on the Moon in general, being up there?

John: Well, I think when we go back to the Moon, everybody's going to learn to love to work up there. It's very unusual because one-sixth gravity, you can pick up the equivalent of 100 pound sack of Moon rocks and jump flat footed.

About two to three feet off the ground, wearing a big pressure suit that weighed 300, my pressure suit and I weighed 360 pounds and we could jump real high off the surface.

So and everybody's going to love that gravity feel. When you go to bed at night and we slept in hammocks and it's just like sleeping on a feather bed, even though there was no blankets or anything in there, because the gravity feels so wonderful. So everybody's going to love that.

Paul: I hope some of the students are watching this today are going to get inspired enough to want to become astronauts and hopefully get up there.

John Young: Well, I think before the end of this century, there'll be a lot of people living and working on the Moon and probably Mars, too.

Paul: I hope so. There is, actually three students came up with the same question. Christy, Heather and Michael wanted to know, what influenced you to become an astronaut?

John Young: Well, you know, President Kennedy back in 1962 said he was going to send a man to the Moon within the decade.

And return him safely to Earth. I like that part about returning safely to Earth, so, I told all my buddies we should put in for it. We were test pilots at the Naval Air Test Center at [Production River].

And so a bunch of my friends put in for it and we were lucky enough to get selected.

Paul: Kimberly wanted to know what do you find most interesting about what you've seen and about what you've done?

John Young: Well, the whole business is an interesting thing. I think what we've learned from exploration of space, tells us that we need to be ready to go back and explore and eventually colonize places like the Moon and Mars. And the other places in the solar system because we have some evidence that from the extinct, mass extinctions that have gone on in the planet earth, single-planet species don't last forever.

So if you have the technologies to be able to work on the Moon and Mars, why you also have the technologies to protect the people on planet Earth that bad things like asteroid impacts or super volcanoes occur. And we're just now getting to the point where we can build the technologies that we need to build to literally start controlling our destiny. We didn't have that capability in the 1800s and the 1900s, and now in the 2000s, we're being able to develop that.

Paul: If you could have some words of advice for our viewers who might consider working for NASA as scientists, as engineers or even as astronauts, what would you tell them?

John Young: Well, I think everybody that's a young person should be doing what they do the best and what they like to do, whether it's teaching other children or writing poetry or playing music or if you like quantum mechanics, why NASA's probably the place for you.

And I think you should do what you do, what you like to do and do the best you can at it. And if you get to be an astronaut, okay, and if you don't, you can be an engineer or a scientist or a musician, I think that's, I think you should do what you do best.

Paul: Just before, it's okay, we're going to watch John for a second.

But just before we take another question, I want everybody to give a big round of applause for John Young for taking the time to answer those questions. Really amazing to get to talk to an astronaut that has walked on the Moon. Okay, now let's go back and take a question. Sorry about that guys.

John: Paul you have a question here. I think it's a really good one. What are some ideas for space scientists, government and environmentalists to work together to take care of the Earth and of space [continue to damage] our Earth?

John: Wow. There are just tons of great ideas we have about conserving our resources, recycling, reducing, reusing and trying to find, for example, energy sources which have less impact on our environment, things which, for example, don't produce as many greenhouse gases, things which are renewable energy sources, and there are a lot of agricultural ideas.

I could run on and on and I'd be willing to bet that Nathan actually has a lot of ideas for this, too. So you can ask him.

Nathan: Repeat that question?

John: About the ideas to help protect the Earth so we don't continue to pollute and damage our planet.

Nathan: Well, for one thing, our name Lakota, the interpretation in English means friends to the Earth. And one thing we do is we try to take care of the Earth so that it will continue to help us with pure water, purify the air. But the question there can go a long ways. And I could say that would be one good thing that NASA, a good idea for NASA to look into other ways of like what you said, energy saving and cleaner air, cleaner water, things like that.

And I think the person asking the question would be probably concerned about the shuttles going up in the air and like that. So it could go a lot of ways, but we'll work on it with some of the ideas we keep working together.

Aimee: It's a really good question and I'd like to add that it's very important for the government to work together with scientists because scientists work very hard to determine if a trend that is alarming the people, if a trend is true, such as global warming, and then when they get the results, the government and the people who make policies need to pay very close attention to what science has proved and what it disproves and how they can work together.

Paul: Great. What I'd also like to do is we haven't taken a chance to do this yet. Maybe we can bring up one of the images from one of the telescopes that we have out there and see if we can get that up on the screen.

And maybe we can get one of our scientists to describe a little bit about what are we seeing here. So one of you solar type scientists, maybe you can tell us a little bit about what we're seeing on the screen.

Marc: Sure.

Paul: You can go up to the screen if you want.

Marc: Well, this cares to be an image of, in regular visible light of the solar photosphere. That is to say, the surface of the Sun that we can see in visible light. And I believe this is an image taken either yesterday or today and you can see that there's about, looks like about seven or eight sunspots that are fairly small on the solar disc today.

And at times, as I alluded to earlier, the Sun shows many more sunspots and in different places. And right now, we're in the phase of the solar sunspot cycle where there are getting,

where the number of sunspots is getting progressively fewer. And so in this image, as you just saw,

Back to shot of the sun with sunspots

There were very few sunspots on the disc and there will continue to be fewer and fewer sunspots until the rise of the next cycle.

Paul: Does everybody know what a sunspot is or do we want to ask our scientists what's a sunspot? I think we want to ask our scientists, what's a sunspot?

Marc: Well if you could go back to the image.

Back to shot of the sun with sunspots

A sunspot, as you can see, is just a dark splotch on the face of the Sun. And that's an area, it turns out, where the magnetic field that's penetrating the surface of the sun is very high in intensity. And as a result, what that does is it stops the light from coming up through the surface of the Sun, and as a result it looks darker.

Paul: How big are some of those sunspots that we're seeing in today's image?

Marc: I believe they're probably, I don't know, maybe 20,000 to 50,000 km across.

Back to shot of the sun with sunspots

And that's each one can be several Earth diameters in size.

Paul: So the majority of those spots that we're seeing in the image right now are the same size of the Earth, if not bigger?

Marc: That's right.

Paul: Those are big spots that are out there. Well, since Marc's been doing all this talking, I think might as well we try and get him to continue talking a little bit and find out a little bit more about our scientist here. Marc, tell us a little bit about what do you do?

Marc: Well, I do a couple of things. One thing I do is I observe images similar to the one that was just shown, and look at the surface for patterns of convection. And what convection is, is the way that the outer layers of the Sun transport heat that's generated in the interior out through the surface and then once it gets to the surface, it can stream freely out into space and do things like warm the Earth and so on.

Paul: And something else, what do you find so cool or exciting about your job?

Marc: Well, one thing I find exciting is that I work in a place where not only the scientific instruments that took those images were built.

But also that as a result of their being built there, the data come streaming in through the lab. And to be able to interact with that data on a real-time basis is really exciting.

Paul: And what made you choose solar physics as a career?

Marc: Well, I didn't start out by saying I wanted to be in solar physics. What ended up happening is when I was in college, I didn't really know what I was going to do, but I knew that I was good at math and science. And so as a result, I got involved with a physics lab.

And that ended up being a solar physics lab. And since then, I've been into solar physics ever since.

Paul: Do you have any hobbies or other interests outside of solar physics?

Marc: Yeah, for one I'm a big sports fan. But I also like to do a lot of hiking around here as well and I've done hiking in other places that I've lived, such as Colorado and so I enjoy the outdoors a lot.

Paul: Great. What we're going to do is take another question from the chat room while we get the next group of students to start coming down. So, John?

John: Okay, we have a question from Joseph, who's 13 years old. He asks, when will the Sun begin to mature?

Marc: Well, if you mean mature in terms of, I suppose the easy answer to this question is that the Sun is evolving as a star. And right now it's in a phase of its lifetime where it's burning hydrogen into helium and that's what produces the light you see. And it will continue to do that for another 4.5 billion years, that's billion with a ‘b', and so there's nothing to worry about in terms of our lifetimes. But eventually, it will run out of hydrogen fuel and enter a different phase of its lifetime.

Paul: Pretty cool, I never thought of the Sun maturing.

Paul: Thanks. Okay, down here with me now, we have another group of students and what did you guys wind up doing and what do you have here?

Student: All right, this is how big the Sun is and how small the Earth is, so we're comparing.

And if the Sun was this big, our Earth would be this big. The real diameter of the Earth is 12,750 km.

Paul: And I think Anthony's going to say something.

Anthony: And the Sun diameter is 1 million and 390,000 km.

Paul: So yeah good. We've got a close-up over there and you may want to sort of point to the Earth with your hand there and just sort of show how small and tiny that thing is. That is really great.

Student: These right here are called solar flares.

Paul: And solar flares. Wow.

Okay, thank you. What do we have down here, guys?

Student: How big the Earth is from the Sun and the, we've got solar flares and stratospheres from the Sun going on there.

Paul: So what we have here is you're describing the Sun-Earth distance?

Student: Yeah.

Paul: The distance between the Earth and the Sun and I don't know if you can get a close-up down in here. There's something kind of really interesting there.

Looks like some drawing of pieces of metal or something and if you can describe that? Which one of you guys is going to do that?

Student: This is just a scale of the distance between the Sun and the Earth. This right here is showing you that there's more space between the Sun and the Earth. The actual distance is 149 million, 600 thousand km.

Paul: So really, this big distance would be way too big to bring out here on a chart. But I like the way you guys dragged this all together and taken the two pieces of space and pulling it. This is really great. Did you guys want to throw a question at them or something?

Okay great, well then thank you very much. Let's take another question from the chat room.

Camera showing Dr. John Beck on screen

John: Okay, we have a good one here. It's related to those charts about how far the Sun is away. Ashley, age 13 asks how long does it take for the sunlight to travel from the Sun to the Earth.

Aimee: Well, I can answer that one. Obviously light travels at the speed of light and the distance, as the students just showed us, is almost 150 million km. So I'm not sure the exact number in seconds, it's close to 8 minutes though. Does anybody know the exact? It's 7 minutes and 26 seconds, something like that. But it's close to 8 minutes that it takes the light to travel from the Sun to the Earth.

And that's an interesting question because if you think about how long it takes the light to travel from other stars, you realize that by the time it gets to Earth, it's taken a lot longer to get here than you can imagine.

Paul: Do we have another question?

John: Sure, we have one here that's pretty good. Kyle, 14, asks can the Sun become hotter than it is already and do sunspots get hotter too?

Marc: Well as I said before, the Sun will evolve to a different phase of its existence where, it will actually get cooler in its next phase, I believe, as a red dwarf, a red giant, right. And as soon as I said it, I knew I said the wrong thing.

And so just by the virtue of the fact that it's called a red giant, because light that's colored red actually has a lower energy. That means it's produced by gas of a lower temperature, and so now that it's, right now it's yellow and it's hotter, it'll get redder and therefore, cooler.

John: Could I add something? One of the interesting things about the Sun is as it ages, the outside will cool off, but the inside will get hotter. It will actually get so hot, right now the sun is say about 12 million degrees in the interior, but it will actually get over 100 million degrees as the Sun gets older.

Paul: Great. Well, I've got another group of students up here, two students and what do we have here on the chart?

Student: Four pictures of the Sun about four different months and I measured its diameter and it shows that it stays the same distance around the whole year.

Paul: Are you going to say something on this, too? You're just the official chart holder, okay. Okay so it stayed the same throughout the entire year, taking these images which, just trying to see where they came from, too. That is pretty cool. So basically your conclusion is that it stays the same?

Student: Yeah, the whole distance [around], it doesn't, [well it] stays like [inaudible].

Paul: So as we go orbiting around the Sun, it will stay the same?

Student: Yeah.

Paul: That's great. Well, fabulous. Okay, do we have another question from the chat room? Thank you, guys.

John: Yeah we sure do. Here's one. Hello, my name is Angie and I'm in the 12th grade in science and technology. I would like to know if there is any danger on the Sun that might affect our planet. Any materials that are up there or anything that can affect our planet in some way?

Marc: Well the Sun is constantly emitting particles, that is charged particles such as electrons and protons in all directions.

And some of those particles do interact with the Earth system, and do have the potential to disrupt things like communication satellites. These are the same particles that caused the aurora. And if you've ever seen an aurora, you know what a spectacular display that can be. But these same particles also have the potential to, as I said, disrupt communication satellites and knock out power grids, they've done in the past. So we always need to be aware of this.

Aimee: I'd like to say something too about the experiment that they just showed results from.

And I think what they were trying to say is that they were trying to disprove the misconception that we have seasons because the Earth gets closer or further away from the Sun. And so it doesn't get hotter in summertime because we're closer to the Sun or it doesn't get cooler in the winter because we're further away.

It's actually because what we're celebrating, the equinox, because the Earth is tilted and the northern hemisphere gets more sunlight directly on it during the spring and summer months. So the point of the experiment of measuring the diameter, was a really good one to conclude that you really don't get that much closer to the Sun to make a difference, and the amount of heat we get.

Paul: That's a really good point to bring up. Do we have another question?

John: Oh, we sure do. Jasmine, age 14 asks why is the Sun so close to the planet of Mercury?

Aimee: That's a good question. I don't know. I'm sorry. [laughs] Actually it's not, well Mercury is really close to the Sun. So it's just the way she phrases it. Mercury is the closest planet.

And so when you look at the Sun, so when the Sun sets, often times you see Mercury, or if you see Mercury at all in the night sky, it's very, very close to the Sun. So it's the first planet out from the Sun, so it's always going to look like it's very close to the Sun. Okay?

Paul: I think we've got time for another one to throw in here.

John: Paul, this is a good one. Are you ready for this one? How do sunspots appear and disappear?

Marc: Well, as I said, this is one thing that's not well understood, even today why sunspots occur and how they form. And as I alluded to earlier, the current theory is that you have concentrations of magnetic flux, which are rising from deeper in the interior out through the surface. And you can't see the kind of flux tubes individually, but what you can see is where they penetrate the solar surface.

And this is one reason why sunspots typically occur in pairs as well. So, but as I said, this is an open question.

Paul: And that's a really important point that's being brought up here. One of the things that you out there watching, you students out there and the students that are here in the studio, you may think that scientists know all the answers.

Well, we don't, which is why most of us become scientists, so we can try and find out some of the answers. And the other thing is, is for those of you who may one day want to become scientists, there's still a whole bunch of questions and problems to be solved, and of course every time we try and solve one problem, we wind up discovering a whole bunch of new things which open up a whole bunch of other new questions to try and go out and solve.

So that's kind of the interesting thing about all the scientific research, we don't have all the answers. And that's what makes it kind of fun to go out there and do some of this stuff as well. So up here again, we've got another group of students with us.

And so what do you guys have up here?

Student: This poster is showing the Earth orbit around the Sun and its distance.

On July 4th, the Earth is farther away from the Sun and the distance is 152.1 million km.

Student: On January 2nd, the Earth is closer to the Sun, which is 147.1 km.

Paul: So during winter for us, up here is the Sun closer or farther away, as in January? Is it closer, or farther?

Student: Farther.

Paul: So here it is in January, the Sun is closer to us, yet it's colder. And then in July we're looking at this chart and we're seeing that for us up here in North America, it's summer time and the Sun is actually farther away. So really this is also again showing what Aimee had just concluded over there as well, the fact that the Sun-Earth distance isn't making any real big difference on the seasonal changes.

So most people out there wind up thinking that all the time. We actually wound up going around and asking a bunch of adults, because we had to ask the adults all this stuff. And we found that most of them actually believed that the difference and the cause of the seasons is the fact because the Sun-Earth distance. So all of you up here right now have just proven the fact that a lot of adults are wrong, and the fact is what really is causing the seasons is not this. That's great. That is really great, guys. Thank you. Okay, Marc has something to add.

Marc: Yeah, just real briefly, if you think about it a little further, if the distance the Earth and the Sun were the main cause of the seasons, then both hemispheres would be summer at the same time and both hemispheres would be winter at the same time.

And I don't know how many of the students have had a chance to travel south of the Equator, but you probably have heard that for example some place in Australia will have summer while we, in the northern hemisphere, are having winter. So that's obviously not the case. And that's another way to disprove this common misconception.

Paul: Okay let's move down just a little bit more. Who's going to go first here? Okay what do we have?

Student: Well, as you can see, this is the Earth's orbit compared to the circle. Earth is like slightly like a circle but Pluto is kind of like an oval.

Paul: So what we're really trying to say then is the Earth's orbit, when you guys plotted this thing out, came out to be, is more of a circle than an ellipse or any other shape?

Student: Well Earth is like, it's not really quite a circle, it's almost like a circle.

Paul: Because it is close to being a circle?

Student: Yeah.

Paul: Versus any other type of orbit?

Student: Uh-hum.

Paul: Very cool. Which is why the distances don't change that much when the Earth is going around the Sun. Great. And Pluto's orbit, you have that down there too.

Student: Yeah.

Paul: So that's a much longer orbit, but it's also circular. That's great.

Student: What we've got here is this is a perfect circle and this is like [inaudible] the Earth.

So you can see how close to, how circular it is. We've got the Sun here and the Earth here. And this is just showing how close, how circular is the ellipse of the Earth.

Paul: So you wound up plotting this out and so you've got a perfect circle out here on the far side there, on the right, and over here is more of the ellipse of the Earth's orbit and it looks very much like a circle. And the one thing, of course, I've got to say that this is not drawn to scale. At least the Sun is not drawn to scale, because every other image we've seen of the Sun is much larger. So the Sun is not that tiny.

Any other comments you guys want to make? No. Nobody want's to throw in words here? So when you were drawing this thing out, was this something you had realized was going to happen or is this something that you didn't know about before?

Student: We didn't actually know before.

Paul: So this was kind of a new discovery here?

Student: Uh-hum.

Paul: That's great. Did you guys want to throw in a question here on them or? No? Okay.

Aimee: Would you like it if the Earth had a really elliptical orbit?

Paul: Want to ask that again?

Aimee: Would you like it if the Earth had a really elliptical orbit? Would you like to live on a planet that had a really elliptical orbit or not? Yeah?

Paul: Yeah? No?

Student: Yeah.

Aimee: All right.

Paul: Why?

Student: It's more better.

Paul: It would be better? It would be different. Definitely say it would be different.

Aimee: Them maybe if it was really elliptical, our seasons would be affected by that. Maybe. Yeah?

Paul: Okay, that's great. Thank you very much, guys. And I think what, since we're pointing that way, let's take another question from the chat room.

John: I actually have a really good one here. It says hi, my name is Nassar, I'm in the 9th grade of high school science technology. Do you believe that the Sun heating up could cause global warming? And if you guys don't want to take it, I can field that one.

We can measure how hot the Sun is to a very precise amount, better than a fraction of a percent. And even though the Sun could warm up a little bit within that amount that we can measure, it wouldn't account for all the global warming we've seen so far. So the Sun could contribute to it, but it cannot be the cause of all the global warming that we've seen. Did you have anything to add? Okay. So it's not the Sun's fault, is what I'm saying.

Paul: I also want to take a moment here, maybe we can bring up another image from one of our live telescope images, or almost live telescope images and see what we have here. And maybe get one of our scientists to explain what this other image looks like.

Oh there's an interesting one.

Aimee: Wow. When was this taken? Do we know? Is it live?

Paul: Yeah.

Aimee: Well, it looks like we're looking at a group of sunspots here on the solar surface and you can see how complex they are. They look like they're interacting with each other. A couple of them look like maybe they're merging or moving apart. And you can actually see some of the structure there in those big magnetic fields that we call sunspots.

You can see the really dark part in the center which is called the [ombra] of the sunspot.

Back to the live shot of the solar surface with sun spots

And the part on the outside which is called the [penombra].

But yeah, this looks like a whole active region group, maybe two of them, and it looks like you can see here, you're looking closer to the [limb] of the Sun, so you can really see the curvature of the solar surface there.

Paul: What is the limb that you just described?

Aimee: Oh, the limb is just where the amount of light drops off so rapidly that you can see a clear distinction between what we call the surface of the Sun and what becomes the solar atmosphere. So it's the limb of the Sun is right where the image goes from light to dark.

Paul: So it's basically on the edge of the Sun?

Aimee: Oh, yeah, it's the edge of the Sun, right.

Paul: Great. I think we have another question that John was going to throw at us.

John: Yeah, this is a question for Nathan. So they ask, they didn't say their name, how does the Sun mark the Lakota calendar?

Nathan: Well, the Sun for many generations from the time of our people migrated out of the Earth, we followed the Sun. But how we knew of the Sun's path was to the buffalo. We migrated with the buffalo. And the buffalo, they took us to different places according to the Sun. And with us, everything's connected to the stars, and so the Sun for our people and for many tribes like I said, was very holy, sacred. And we have a dance once a year called the [Wiwangwa Chipi] which is the Sun dance. And our people, we've been studying the Sun, looking at the Sun.

Many of the scientists still can't believe [they've came to the sunlights] and they still can't believe that we look directly into the Sun and we pray with the Sun. And using that energy to go I guess, to find mystery questions that how and what and what's going to happen with the Sun this year, is it going to be a hotter year? And things like that, droughts happening this year.

And so we followed the buffalo a long time ago and so that's how we kept track with the Sun, because the buffalo migrated with the Sun.

Paul: Okay, thank you. We have another student up here with us who has a pretty unique looking chart. And David, maybe you can walk us through and tell us what this is and what you did and what does all this mean?

David: Well, this is a graph showing the difference between certain spots on the Earth like you have 7 degrees north on the Equator and 7 degrees south of the Equator and it shows like for 7 degrees north you have 24 hours of [three months] of nothing but daylight and in certain months and then on the exact opposite side of the, on the bottom there, you have nothing but darkness. And shows how at the bottom of the Earth and the top of the Earth, it's exactly the opposite, like for 25 degrees north at 26 degrees north and 26 degrees south.

Paul: So what we're saying is depending on what side of the Earth you're on, if it's spring up, well if it's winter up here, it'll wind up being summer south of the Equator?

David: Yeah.

Paul: Now from all of this, and from the studying that you and your classmates were doing, where would you like to live, if you had a choice to live anywhere on the planet? I mean now the Arctic and the Antarctic, going for six months of darkness throughout the year, I don't know if that's the most fun place, but if you had your choice, where would you want to be?

David: Right where I am.

Paul: Good answer.

David: Not always dark and not always light.

Paul: That's great.

David: Since the equinoxes for the spring equinox and the fall equinox, and that's like exactly 12 hours of daylight.

Paul: Okay, so you may want to point that out and hold your hand there for a little bit and point out at it.

David: Here and here. These two places right there.

Paul: Okay so those two points are

David: Spring equinox and fall equinox.

Paul: Okay and those points represent with the hours of daylight?

David: 12 hours of daylight.

Paul: Okay so that's where the hours of daylight are the same?

David: Yeah, all over

Paul: Hours of daylight, hours of daylight, and night time, throughout the day. Okay, and that happens at two times of the year and we're at the spring equinox today. And then the other one is in, when is it? September?

David: September.

Paul: Yes, September. That's right, I can read it off the chart here. Great. That's pretty cool. Thank you very much.

We've got time for another question.

John: Great.

Paul: Just before we get to the question, I think Marc wanted to add something, so if you give us a second, we'll just turn it around.

Marc: I've got a question for the audience. They're probably fearing this but I just wanted to ask, even though today is the equinox, and we'll have another equinox in September, does anybody know what the shortest and the longest days of the year are called? There's a term for that as well.

Paul: Anybody know what the shortest and the longest days of the years are called? We've got a winner.

Student: It's the solstice.

Marc: The solstice, that's right, and there's one in the summer in June and one in the winter in December, at least for the Northern Hemisphere, we call them the summer and winter solstices, respectively.

Paul: Good answer. Somebody's been paying attention. Good. Okay let's try and take a question.

John: Andrew from Mrs. Westburry's 7th-grade class asks, I was wondering what are the northern lights and how are they caused?

Aimee: The northern lights are the aurora like we discussed earlier, and there's also lights like that in the Southern Hemisphere called the southern lights, or the, I guess they're called the Aurora Borealis and the [Australis] Borealis in the Southern Hemisphere.

The northern lights are what we talked about earlier where matter from the Sun and charged particles come into the Earth's atmosphere and they stream down the magnetic field lines which are typically close to the poles, the northern and the southern poles. And so that's where you see them mostly, and they cause brilliant displays.

Paul: Have you ever seen them?

Aimee: Never seen them. I'm kind of bitter about that. I've been trying to see them. I've been hoping on long flights, sometimes if you fly to Europe, you'll be able to see them out the airplane windows. But it's one of my lifelong goals to see the northern or the southern lights. Maybe one day.

Paul: Well, I was going to put a plug in this for at the end of the show, but next year's topic is going to be on the aurora. Which will be on the northern lights.

Aimee: Can we fly somewhere to see them?

Paul: Yeah, I think we're going to have to try and convince somebody to fly all of us somewhere, right, to witness this, because I haven't seen them in a long time.

Aimee: Has anybody in the audience seen them? You have?

Paul: One hand up. Well, I saw them. I guess we have a few of us that have seen them.

I think we've got time for one more question before we move on.

John: Okay. Well, this is a short question and it's for Nathan. It says, was Nathan in "Dances with Wolves?" He looks like the character who smiles a lot.

Nathan: Yes, I played the part of Smiles a Lot in the movie Dances with Wolves. [applause]

Paul: And I think actually right now we have a video that we're actually going to show, which ties back into Nathan. And maybe we can start that one up.

Video: The Lakota People are very Sun-centric people.

And the Sun plays a very important central role in their ceremonies.

And within their songs.

And within their teachings and that they share even on a daily basis. For the Sun is the giver of life and just as the Tatanka or the buffalo.

Is a giver of life.

According to the Creation Story of Tatanka, who we call the buffalo.

But if you interpret that, it doesn't mean buffalo.

Tatanka means We Who Belong to the Large Ones, or the sacred ones, the powerful ones.

And according to our Creation Story, the buffalo was a representative of the Sun here on this Earth, for he was, like the Sun, he was a giver of life. He gave of himself so that others would live.

Paul: Back to us live over here, one of the other guests we have with us is Nathan Chasing Horse and we haven't had a chance to actually talk to him a little bit. And besides the fact that okay we all now know that you were in a particular movie, and tell us a little bit about yourself.

Nathan: Well, since Dances with Wolves, even before that, I used to get up in front of gatherings that we would have such as the Sun Dance or pow wows or other ceremonies that my grandpa, or my grandfather would have and I would get up and I would speak on how I would feel or if I had some concerns or I would talk a little bit about what I was experienced, since I was a little boy.

And since Dances with Wolves came out, I went to the audition and was blessed with the part. And since Dances with Wolves, I've been traveling throughout the country, mostly to the reservation schools throughout Native America and speaking about drugs and alcohol and family values and spirituality and all these things to follow our given ways of life.

And I was reluctant, I was able to work with NASA for the past couple of years developing a curriculum-based on Lakota star knowledge. And a lot of our star knowledge goes according to the Sun, when the Sun are in those constellations. And we're at specific places on this Earth doing certain ceremonies, picking certain medicine.

And a lot of those ceremonies are coming back and we're yet reviving some of the ceremonies today and welcoming the [thunder beings] is one of them. Bringing the children there, making offerings and asking for a good year and being thankful for the year that they were able to come back to begin a new cycle.

And so I've been using the character Smiles a Lot and actually I'm getting ready to do another TV show called Dream Keeper and we start filming in May. And we'll film all the way until August and it will be out sometime next spring. It's called Dream Keeper for ABC.

Paul: One of the other questions I was going to ask you is what is some of the differences between your own star lore and from the Lakota tribe, versus the standard or more standard constellation type naming that us as scientists have gotten used to?

Nathan: The Greek mythology?

Paul: Um-hum.

Nathan: Some of the stories are similar how they came about, but a lot of the stories that we have were like I guess given and events that had happened thousands of years ago.

And I guess how we could say the Creator put those constellations there so that our people will be reminded and how we followed the stars for different medicines and be reminded of responsibilities that we had. And so we followed these stars and the Sun. But the thing is, with the western society, they go by what they see at night, and we don't. We go by the day, when the sun is in the constellation.

Paul: A little different.

Nathan: Yeah, a little bit different. Everything is somewhat contrary, but yet the same.

Paul: That's great. Do you have any hobbies or interests?

Nathan: Well yeah, I'm working on my new outfit, my grass dance outfit beadwork. It's one of my hobbies, I love artwork, doing things with my hands, making things and also dancing and the grass dance, traveling with different pow wows and enjoying myself that way, expressing myself through my movements. And basketball and like that.

Paul: Good stuff.

Nathan: Yeah.

Paul: Okay, I think we're going to have another video coming up here in a moment as well, so maybe we can go ahead and roll that? And then we'll come back to Nathan and find out a little bit more about it.

Video: There has been many misunderstandings, many misinterpretations of who the Lakota People were and who we are today. And a misinterpretation of many of our words, of many of our ceremonies, thus we were misunderstood as a people.

Such as the word Sun Dance. When you say [Wiwanwa chipi] in my language, it doesn't mean Sun Dance. What you're saying in my language is dancing in balance in the circle of light, looking carefully at the sun, and that's the correct interpretation for the Sun Dance ceremony.

The Sun Dance is a gathering of thousands of people that come together and they build a huge circular shape arbor with 52 poles in a circular shape.

And these poles are aligned with certain stars. And particularly with the four directions.

And after the arbor is constructed in a circular shape, this is a place where the people who come to observe the Sun Dance ceremony come and sit under the arbor in the shade. Where the participants of the Sun Dance, they are in the middle of the circle where there's no shade. They're under the direct light of the Sun.

And there was a sacred tree of life of a cottonwood tree that has the symbol of a ‘Y' that is erected at the very center of this circle, of this arbor.

And from this tree, there are four sacred colors that are hung from this tree.

At this time, the sacred Sun Dance ceremony is performed. It's a 4-day ceremony.

In which individuals who participate prepare over many years, prepare to participate in this ceremony

because it consists of fasting for four days with no food or no water.

And dancing in beat to the drums, to the singing and for four days this individual, once again, takes himself into the circle and there he dances.

And this symbolizes a time in our lives when we take from the Earth all that our body partakes and the water, the food, the medicine, the energy. There comes a time in our life when we have to give back to the Earth that which we have taken.

And so the Sun Dance is a time when we give a flesh offering, thus symbolizing that, once again, to keep the balance of life, we have to be willing to give back to the Earth that in which we have taken.

It also is a ceremony in which they train the younger men and women to stargaze, to look into the stars and to learn the Falling Star Stories, the songs and the ceremonies that come with these sacred ceremonies.

Within our Sun Dance ceremony, we have many, many different songs and some even, these songs are so ancient.

And so old that they go back to the beginning. One particular song is, when the ceremony is going to begin.

On the first day of the 4-day ceremony, there is a song that is sung while the dancers are going into the circle. And they stop four times before they enter into the circle. And the song says, "I am coming before the Sun, one to four days, I am coming before the Sun." And thus, symbolizing a force of energy,

of power that's coming from the Sun to the Earth.

And within four days of the 4-day ceremony, this power or this energy will reach the Earth.

Paul: That was really pretty cool. Nathan, maybe you can say a few more words about that or describe a little bit more about it. In particular, who is that gentleman that we're seeing here in the video?

Nathan: That's my father, Joseph Chasing Horse. That's my father, that's the man who raised me.

Paul: And can you add a little bit more about the Sun Dance and star knowledge?

Nathan: Yeah, the Sun Dance is a very sacred ceremony to our people and we're not really allowed to go into details about the ceremony. But I could talk about the teachings that I have received from the Sun Dance myself.

It began for me when I was 12 years old, and at that age, my tribe, my people, we believe that's when a young boy becomes a man, at the age of 12. And at that age a long time ago, they were already hunting buffalo. They were doing responsibilities of a man; hunting, going into I guess, battles or fights.

And our people, a long time ago, we never took each other's lives. It was more for like Olympic, like we stole each other's horses and like that, that's how it was.

And so our young boys were initiated at the age of 12 and at that age, that's when like I said, a young boy becomes a man and he gives of himself, endures that pain and gives of his body back to the Earth in symbolizing he's going to live the way of life of giving and understanding, and respecting his family, like that, this way of life.

And so the Sun Dance is very hard. It's one of our difficult ceremonies. You don't eat and you don't drink water for four days and you dance in the hot sun looking directly into the sun.

And praying. And my father, he's been doing it half of his life. I've been doing it half of my life and we still have 20/20 vision, looking into the Sun.

Paul: That's pretty amazing, because most of the time we tell everybody do not look at the Sun. That's pretty cool stuff. Thank you.

We have one last guest that we haven't had a chance to talk to and introduce a little bit. So let's have a talk here with, this is John Beck, and he's the one who's been telling us all these wonderful or sending us all these questions. And John, tell us a little bit about yourself, what do you do?

John: Well, I'm a solar astronomer at Stanford. I look at something called convection inside the Sun and you're all familiar with convection; hot air rises. And that process of heat rising to convection occurs in the outer about third of the Sun. And that's what I specialize in.

Paul: And what is so exciting about your job? What is so cool about it?

John: Well, I guess for me, the most exciting thing about doing research is having the opportunity of seeing something, understanding something and being the first one to see it.

Paul: There is actually, I just want to mention one thing about it, for those of you who may not be professional scientists yet, amateur astronomers have the opportunity to discover comets that get named for them.

Several years ago, some of you may remember comet [Haley-Bopp] that was discovered by two amateur astronomers here in North America. There's actually a comet out right now, you can see in binoculars that was discovered by two amateurs, and I just found out another comet was discovered earlier in the week by two amateur astronomers.

So one of the coolest things is to be one of the first people as you say, to see something new that nobody else has ever seen. Nobody else on this planet has ever seen. So it's kind of fun stuff, why we do all this.

Paul: Why did you choose this career?

John: Well, as a kid I always liked figuring out how things worked, what made them tick. And when I was a graduate student studying physics, I had an opportunity to work at a solar observatory. I found it was very intriguing the techniques they used to try and figure out how the Sun works. And so that's what got me hooked.

Paul: And since I've been asking everybody else these types of questions, do you have any hobbies?

John: I have a couple of hobbies that I can mention. One I like to ride motorcycles and another I do standup comedy.

Paul: Okay, well I'm not going to force you to do jokes here right now for us, but great. Thank you so much. And get back over there because we need to get another question up here from the chat room.

John: Question from the chat room. We have a question. Which is better, to get a tan by laying out in the Sun or go to a tanning salon?

Aimee: Neither is the preferred answer, because I believe, I've never been to a tanning salon because ultraviolet rays can hurt your skin. And we actually did a Web Cast, the first Webcast I was on was about ultraviolet rays and how we needed to try to avoid those to not cause skin damage. But I'm not sure, maybe someone else knows, are tanning salons trying to be more careful and does anybody know that answer?

I still think that the less amount of radiation your skin sees, the better. The healthier it will be in the long run. So even though you might think it looks good now, it's not healthy for you.

Paul: And just to add into that question, what was it like when you were living down in Australia? What was, a little bit different than up here.

Aimee: Oh right. That's a good question. Actually the Southern Hemisphere experiences harsher ultraviolet rays, so if anybody's every traveled to Chile or Australia, for example, they actually have worse ultraviolet radiation and you need more protection.

Everybody in Australia, all the kids when they go outside, they have a campaign called slip, slap, slop, which is slip in a shirt, slap on a hat and slop on some sunscreen. And you never see kids in the Sun, in the ocean without a hat on and without maybe a little shirt on to protect their skin. So the Southern Hemisphere, people take it very seriously, the ultraviolet radiation.

Paul: Did you want to run through that one again, it was slip, slap...

Aimee: Slip, slap, slop. So it's slip on a shirt, slap on a hat and slop on some sunscreen.

Paul: Can you say it real fast, too?

Aimee: Slip, slap, slop. I might embarrass myself if I try.

Paul: I think we've got time for one more to throw out there.

John: Okay, we have a question here. My name is Keeta, from Springfield, MA. What advice would you give future space scientists, in what way can they help the world? What will happen to the Earth after the Sun burns out?

Marc: Well, there's a lot there. As far as advice, I would say if you want to become a scientist, keep asking questions. I think for scientists, it's more important to ask questions than to find out the answer to things, and in many cases, once you do find the answer, that raises even more questions. John, what was the rest of that?

John: What will happen after the Sun burns out?

Marc: Well, if by burning out you mean the Sun runs out of hydrogen to fuse into helium, as I alluded to before, that will happen in about 4.5 billion years, and so you don't need to worry about it just yet. And so what will happen is the Sun will kind of puff out as our atmosphere and, in fact, engulf the Earth. So but as far as the star is concerned, it's just another phase in its evolutionary cycle.

Paul: So I think part of the main point of all that one is that we should heed the words of advice from John Young and start getting back out into space, because in 4.5 billion years, we'd better find a new home.

Okay, with me up here in the front, as some of you can see, we have another group of students that are up here. And they've got a couple of charts up and, no these are blown up. These are cool drawings.

Okay, what do we have here and maybe you can describe what the activity was and what these drawings are.

Student: Okay, what we did was we started in early February and what we would do is we would pick a spot out in the front of our classroom and we would go to that same spot every day that we had class and we would look at the Sun and then we would kind of graph on these pieces of paper. And as about a month went on, the Sun just kept going higher and it started moving to the right a little bit and the left, but other than that, it just went straight up.

Paul: So you started these observations when?

Student: At about early February.

Paul: Okay so have you got a date down there? I think it says February what is it, the 5th?

Student: Yeah.

Paul: And these observations went until?

Student: They're still going.

Paul: And they're still going? Okay because I'm just looking at the last one here is what, March the -

Student: 14th.

Paul: ...14th. And that was the same one here too? Did you do this drawing here?

Student: No. What he's explaining is as it goes higher, it's getting warmer.

Paul: So our temperature outside have been also changing?

Student: Yeah, it's rising.

Paul: And the other things [you're making of] this was at the same time of day that you did these observations?

Student: Yeah, we did them at the same time every day.

Paul: Okay, so at the same time every day the Sun was getting higher in the sky?

Student: Yeah, we were in a different class, so it depends on which class you were in.

Paul: Very cool. So as we're getting from winter into spring, the Sun is getting higher in the sky. That's a good thing. And that also ties in with the number of hours of sunlight that we saw from the other classes as well. Very good stuff. Thank you very much.

And of course, another question. There's lots of questions in the chat room.

John: This one says hi, my name is [Sohailaf]. I hope I pronounced that correctly. I am Persian. I was just watching your TV station, I was very pleased. As you may know, Persians have been celebrating this day, actually the hour and minute and second of the Earth finishing yet another rotation around the Sun for thousands of years. This marks our new year. The question is according to our calculations, this event will happen at 11:16 AM Pacific Standard Time. You said it will happen at 1:15 PM Pacific Standard Time. So, who is right?

Camera shows guest panel

Aimee: I have no idea. It's pretty close together. I think that's 11:00 to 1:00 we can celebrate the whole time. [laughs] I don't know, I honestly don't know the exact time. I guess the time changes every year because all I know to do is to explain it scientifically.

Which is the reason the time, the date and the time changes every year is that the amount of time it takes for the Earth to go around the Sun isn't an exact number of days. It's 365 days and a quarter. So it changes every year, the exact time and day of the equinox.

But I don't know how to answer that question. We'd have to research it further. Does anybody have anything to say? We'll look into it and maybe e-mail you back.

John: Okay, another question. Hi, my name is Derek, I'm 14 years old, from Springfield, MA. I want to know if there are other Suns as radiant and as magnificent as ours in different galaxies?

Marc: Well, yes. And, in fact, in our own galaxy there are lots of stars as you know just by looking up at the night sky. And there's almost certainly stars similar to our Sun in other galaxies as well.

Paul: Great. Well with me up here in the front is some more students and we've got a couple more charts here. And you're going to explain to us what they are, what you did and what is this?

Student: These are graphs of how long the sunrise and sunset is in the area. We got the information from the Navy specifically for our school. The bottom line, at the bottom of the pink, on the March graph it says where it rises and when it sets.

We did this every day when we walked into the classroom.

Paul: And so this is for our location here, and this is only for the data that we saw from the previous picture of just February until March?

Student: That one's February, this one's March.

Paul: Okay. So it's pretty consistent for that month?

Student: The days seem to be getting a little bit longer every time by maybe four minutes at the most.

Student: Just by a minute or two. Or maybe three.

Paul: He keeps coming up here? I keep looking over here, it's the same guy. Okay, anything else on this one?

Student: No.

Paul: Great. Okay, thank you. I think we've got another question of course.

John: Well, actually we have an answer. I was just handed this note from someone and they said that their understanding is the equinox will occur at 11:16 Pacific Standard Time, that we were mistaken. However, I'd like to point out that the Stanford people said it was 11:16 and this note saying that we're mistaking, came from someone from Berkeley, so it may be biased.

Paul: No, I said it was at 1:16. And they're saying it's when?

John: 11:16.

John: But we do have a question. Douglas from Winston Salem, what do you use to look at the Sun and to take photographs? And are they from satellites?

Marc: There are several different scientific instruments used to observe the Sun. Well, the spacecraft that's most well known and that is currently up in orbit is called SOHO, which stands for Solar and [hemospheric] observatory I believe. And on that spacecraft, there are actually I believe 11 instruments that observe the Sun in different ways and at different wavelengths of light.

On the ground, we also have several dedicated telescopes in the United States and around the world, which observe the Sun in naturally typically sunny places such as Arizona and there's also a solar telescope around Big Bear Lake in California. And around the world, there's observatories in the Canary Islands and in Australia and in other places as well. You have anything to add?

Aimee: No.

Paul: Unfortunately, lucky for me, I happen to have, we're going to keep this going. This little debate going all day here. I've got the Observer's Handbook: 1:16. But you can verify, maybe I did the math wrong or something like that.

It says 1916 universal, so it's okay.

Okay with me up here are some more students. See this is when it gets to be a lot more fun in the show. With me we've got some more students and you've got some props up here and some things and you're going to describe what all this is and what activity you wound up doing here.

Student: This is a display that we did for our class. What it is, is we were, we measured this so it was 2 inches off and depending on what centimeters, excuse me.

And depending on what city you had, this is Melbourne right here in Australia.

And right above me it's Singapore and if I could find it, it has Houston, and there's Nome, which is in Alaska.

Paul: So you were measuring the amount of sunlight that was, or trying to measure the angle of sunlight that was coming down from the Sun on different places on the Earth?

Student: And depending on like where the place was is the angle we tipped it. So we like drew the Sun. So this is the Sun and this is like the area that it would be pointing into.

Paul: Great. And I believe there's going to be some more charts coming up here with all of that?

Student: Yeah, uh huh.

Paul: Okay, so we're going to let you guys get those charts. Thank you very much. And let's take another quick question in-between and bring up the charts.

John: Okay, we have an interesting question here from Andrew. How can scientists determine when the equinox happens before seeing it?

Aimee: I guess it's a pattern that's recurring every single year, so it's something that we know is going to occur and we know why it occurs, which is that the, I guess the center of the Sun is passing directly over the Equator at noon on that day. And so we know it's going to occur on a certain, I don't know how we predict these things.

We just know that it's going to occur on the same, close to the same day every year. And like I said earlier, we do have a leap year, we have to add in a day every four years, so it's not exactly the same day.

But we know that we revolve around the Sun and we know when it's going to be the solstice and the equinox and they occur about the same time every year. And we know that pattern occurs. So that's how we know it.

Paul: Okay.

Aimee: Anything else?

Paul: That's fine. As you can see, we've got more students up here in the front and some more charts and maybe you can explain what are we looking at here?

Student: These are the results of the flashlight activity we did. What they show is closer to the Equator. The smaller the circle is as in Singapore,

Paul: So let's go over here to the Singapore one.

Student: 1 degree north which is right above the Equator, which means this is so close to 90 degrees, it covers less area. The sunlight covers less area and it's hotter. The bottom of the graph is the angle of the Sun on March 15th.

Paul: Okay, so just explain this for a second here. This circle here was with the flashlight at 90 degrees and then you tilted the flashlight 74 degrees, which would have been the angle of the Sun hitting Singapore on March 15th?

Student: Yes.

Paul: Okay and that's the size of the area that was covered?

Student: Yes.

Paul: Great.

Student: And in Nome, Alaska, since it was so high above the Equator, it would have taken like six or seven papers to do the entire circle with the amount of light with 60, with 22 degrees [floating].

Paul: And we chose Singapore because it's essentially on the Equator, right?

Student: Yes.

Paul: And so again, comparing what we have over here, this circle here was just the flashlight covering that area, and here was the area that was -

Student: That's why it's so cold because the sunlight is spread out so far.

Paul: You want to say that again just so we make sure we got that?

Student: That's why it's so cold, because the sunlight is spread out over a bigger area.

Paul: Great. And what about these other cities? Did you want to cover those, too?

Student: This one has a bigger circle because it's farther away from the Equator, but it's south, this is Australia. So, this would be during our winter time, I think. Yeah, so there's summer.

Paul: And one of the other things to just make note of is the fact that you've written down what the latitudes of these cities are and does anybody here know what the latitude of us is right now, where we are located here in the San Francisco Bay Area, what our latitude is? Anybody know? Got somebody over there that knows.

Student: 38 degrees.

Paul: 38 degrees or 37.5, close to that. So essentially, what city do we have up here that's almost opposite on the Earth that's close to where we are? And I think it's right down here in Melbourne. So basically Melbourne is almost like our sister city down there. So essentially when we have summer up here, they're going to have winter down there and when they have summer down there, we're getting winter up here. Do you want to explain anything about Houston?

Student: It's] about the same.

Paul: Okay, great. Thank you very much. Okay let's take another question from there? No.

Paul: Okay, we've got one more thing here.

Student: Okay, this is an analogy we thought of for this activity. If I have a box of candy bars and I give it to one friend, then that one friend will have five times the energy. If I have five friends and give them one candy bar each, then they'll get the energy that they're supposed to get. But if I have seven friends, or 35 friends, then I have to cut each bar up into seven pieces, not giving the, only giving them 1/7 of the energy.

Paul: Actually that's a great analogy, except for one slight problem, because as far as I'm concerned, you only have one friend and these are all for me. So, these are all mine. Thank you very much. I think we've got another question here.

John: Yeah, we have a good question here. It's from Shawn and he asks, how can astronomers determine the distance between the Earth and the Sun? If you like, I can field that one.

They actually have to use two principles, one is called Keppler's Law which tells us that the period for the planet to go around the Sun is related to how far it is away from the Sun. And from that we can get ratios like Mercury is say 40% the distance as the Earth is, and Venus is 70% the distance of the Earth. But we don't know in miles what that is.

So the other trick the astronomers use is they look for when Mercury or Venus crosses in front of the Sun for us and they send people to different parts of the Earth and look at where it crosses. And that actually, when they measure that, it's like measuring a very, very narrow, long skinny triangle. And by using that small angle, they can calculate how far it is from the Earth to the Sun. That's it.

Paul: Thanks, John. It's nice to get you to answer one occasionally, while you're sitting down there. Put all the pressure on you for a change. Well we have up here again, we've got another group, actually it's the same group of students. They just did an awful lot of work to do all this stuff. And we have a bunch of different charts, so you're going to explain to us what the charts are, what they mean and what do we have here?

Student: What we have here for Melbourne is this black line right here going down and up, is, I believe that is the angle of the Sun for Melbourne for the whole year. And these bar graphs right here, is the hours of daylight. And as you get into the middle of the year, the hours get lower. And these black lines going down here, indicate the seasons. You've got summer, fall, winter and spring.

Paul: So this was a plot from data that you had and actually taking a look at this, what we're seeing is the correlation between the number of hours of daylight and the angle of the sun and the altitude of the Sun, angle of the Sun.

Student: Yeah.

Paul: Does that sort of match here?

Student: It's telling you throughout the year how the Sun just keeps getting lower and then higher even for the hours of the Sun, too.

Paul: So yeah, so what we're seeing here is as the angle of the Sun gets lower in the sky, the number of hours of daylight is also shrinking as well. And when it gets higher back up in the sky, so does the number of hours of daylight.

Student: Yes.

Paul: Okay so the other charts here?

Student: It changes for every chart. For Houston here, the angle of the Sun keeps rising and then as it gets later into the year, the angle gets lower, and that's the same with the hours of daylight with Houston.

Student: As it gets more into the summer, it gets higher of hours of daylight.

Paul: And what about the other two here. These are different cities?

Student: This is Nome and that's Singapore. Nome here, you start off with a low angle of the Sun since it's so high up on Earth, it just keeps rising up and up until it reaches summer here, and then it starts dropping back down. And so the hours of daylight increase and decrease also.

Paul: And the interesting thing here about Nome is if we take a look at this graph here, the number of hours of daylight in the winter as in January or December, the number of hours that I can see from this graph here is like what two or three hours of daylight? That'd be horrible. Yet at the same time if you take a look what it is in summer there in June, you're getting almost, what is it 21 hours? That's almost an entire day of daylight. I like the Sun. That'd be great. And what about Singapore here? Singapore's on the Equator.

Student: Yeah, 1 degree north of the Equator. And as you can see, with the hours of daylight, it doesn't really change much throughout the year. So with the angle of the Sun, it shoots up and then goes back down in the middle of the year and then shoots back up and goes back down.

Paul: But the main thing about this is the fact that the number of hours of daylight for a city that's on the Equator basically stays the same.

Student: Yes.

Paul: It's pretty consistent if you want to live on the Equator. That's great. Thank you very much. Good job, guys, really good job. Oh, and wait, there is more. Okay you're going to explain this one?

Student: Yes.

Paul: Okay, you stand over on this side. I forgot there was more.

Student: These graphs are of the correlation between the temperature and the hours of sunlight. The more hours of sunlight there is, the warmer it is. On Houston, you can see it's a little dark and that this is the high and low of every day.

Paul: So what do we have farther down here? Here we can just walk down and take a look.

Student: Nome, it shows us that here on February 1st, there is a large correlation between the high and low and same amount of hours of daylight.

Paul: And the one thing I'm also noticing is what's the temperature like in Nome, Alaska in winter?

Student: Gets down to negative, it looks like it gets down to -20.

Aimee: That's low.

Paul: -20 Celsius is the low. That's cold. That is great. Okay and what do we have over here for Singapore?

Student: Singapore you see that there really isn't much difference, much change between the year.

Paul: So throughout the year the temperature is basically staying constant. And the number of hours of daylight are staying constant as well.

Student: Yes.

Paul: That is great. So there's a correlation here in the number of hours of daylight and with the temperature?

Student: Yes.

Paul: Very cool. Thank you. I'm going to make sure, is there any more hiding behind there? No?

F: I'd like to thank you very [inaudible]

Paul: Thank you, thank you very much. But where's the other chocolate bars? I thought I was your one friend here with all the chocolate bars. Thank you very much. Okay thanks, guys. Okay I think we've got time for another question before we get to the recap page here.

John: Okay well I have a question here that I like so I'm going to throw this one out. There are a lot of them left in the room, but this one says, hi, I'm Emily and I'm watching your show, it's great. My question is if the Sun blew up, which would happen first? Would we freeze or would we burn?

Marc: Well, if the Sun blew up, I think we'd have more things to worry about than whether you're too warm or too cold.

Paul: Say it again.

John: We would burn first and then we'd freeze.

Paul: I think we can just grab one more quick question.

John: Well, this is a good one. It's a little more serious. Hi, Mrs. Wall's class and that is that as soon as they came outside, they saw a change in their ultraviolet bracelets. Bracelets that measure ultraviolet light even though it's cloudy and rainy. Does the cloudiness decrease the ultraviolet rays of the sun?

Marc: It does but there are some rays that still get through, even though it's cloudy. And as a result, ultraviolet bracelets will light up even when it's cloudy.

Paul: So there's still some that's getting through, even on cloudy days too?

Marc: That's right.

Paul: This was actually an experiment that we did last year.

Marc: Right. Which was a lot of fun.

Paul: Okay, what I'd like to do is actually get through a little bit of recap of the show and maybe we can squeeze in a last question sometime a little bit later.

But what I'd like to do here is get our guest experts to sort of recap and throw one interesting point out that we sort of want everybody to kind of remember about the Sun-Earth and Sun-Earth Day and how this all fits. So one of you can go.

Marc: Okay, I'll start since I'm holding the microphone. Well we've seen a lot of interesting charts and graphs here today which just demonstrate basically why we have seasons, and how the seasons are different, depending on where on Earth you live. And I don't know if we've said this explicitly, but the reason we do have seasons is because the rotation axis of the Earth is tilted a little bit, from the plane of the Earth's orbit around the Sun. And if that were not the case, then we would not have seasons.

I don't know if you've ever thought about how life would be different if we didn't have seasons. Do you have anything to add to that, Aimee?

Aimee: Well there have been a lot of good points that everybody's made out there. One being that our seasons don't come from being closer or further away from the Sun. But I think a lot of the show with the ceremonial aspects that we've seen on the video, I think it's always nice. It's fun to do all the science and look at the numbers and try to get things right, but not to lose sort of the awe of we live in this amazing physical environment that allows us to have seasons and the planet Earth is an incredible place to be and not to sort of lose the magic of what we live in. And honoring the equinox and the solstice are part of that.

Paul: Yeah it's kind of interesting because in our modern culture, the way I know college students try and celebrate the equinox, they have a different name for it. It's called spring break. [laughs]

So it's kind of fun to take the time to celebrate the equinox in a more, I would say in a better fashion. Nathan?

Nathan: I'd just like to encourage the students to the questions that you have. Maybe some of the professionals in this field wouldn't be able to answer for you, so maybe those are goals that you can answer yourself. Go out there and find that knowledge, because that's like what my father always told me and we always tell the youth throughout the country that a long time ago my people, we used to hunt the buffalo to survive.

We used the buffalo for medicine, everything. They were our tools, our food, our homes, our clothing, they were everything, our fuel. And that's all we needed to survive. But now we're in a different time now and so even with the Native American students, in order to survive in this world now, you have to hunt that knowledge in order to survive.

And so I just want to encourage those students back home, [Erwin Shar Fish] the Wounded Knee School, the sixth-graders there and as well as all the schools back home on the reservations that might be watching this, try your best in school and some of the questions like a lot of the students have online and some of those questions you might be able to answer for yourself. I encourage you that way. Thank you.

Paul: John?

John: Well, my only comment, actually it fits in really well with what Nathan was saying about pursuing knowledge. I want to point out that all of these tests, these experiments these kids did to test whether hours of sunlight and the angle that sunlight comes down onto the Earth, whether these things affect the seasons. They didn't need million-dollar instruments to do these. They could look up the hours of daylight, they could look up the numbers and they could measure the height of the Sun using a stick in the ground.

Using very simple tools, you can actually answer a lot of scientific questions. You don't need to have million-dollar observatories and these things. So it's good for everyone to go out and be inspired to pursue knowledge with whatever tools you have. That's my point.

Paul: Thank you. Well, as we're trying to recap the show here, and say a few last words, I'm trying to get everybody to come down here as well. And just want to mention a few quick things before we go out.

I'd like to, first of all, I'd like to thank all the students that came here today, so give yourselves a nice big round of applause.

Of course I'd like to also thank all our guests here, our guest experts for coming today and sharing their knowledge with us. [applause] And I'd also like to thank the teachers and the parents that drove some of the students in here today. Thank you for bringing them in. [applause]

And also the telescopes that were out there online helping us out and to all you students that were out there asking us questions and all the classrooms around the country asking the questions. And to all the other NASA centers that were connected and took the time and the effort to go ahead and go out and educate some of the teachers who went out and helped us with all of the students.

A few other things. I'd like to thank the Maryland Science Center and Ray Lopez's group at Insight. And also coming up, next year is going to be, we're going to have another Sun-Earth Day, of course. It's going to be live from the Aurora. We're going to talk about the northern lights and also coming up on PBS on March 28th is going to be a show called Have a Solar Blast that NASA also produced. And next year's show is going to be on March 18th, so come back and stay tuned and everybody out there.

This is goodbye from NASA-Ames Research Center in Mountain View, California. And happy equinox everybody!