1
00:00:00,000 --> 00:00:28,160
All right, hey, what's up? I'm Aaron Carter, and just to let you know, I always use a lot

2
00:00:28,160 --> 00:00:34,760
of math, science, and technology in my concerts and shows. That's why I want you to watch

3
00:00:34,760 --> 00:00:40,040
the NASA Wi-Fi. It's great. It makes learning math, science, and technology fun. So stay

4
00:00:40,040 --> 00:00:43,120
right where you are and check out the NASA Wi-Fi.

5
00:01:10,040 --> 00:01:20,800
When it comes to solving the Treehouse Detectives' latest mystery, you need to answer these key

6
00:01:20,800 --> 00:01:32,240
questions. How does light travel? How does the problem board help the Treehouse Detectives?

7
00:01:32,240 --> 00:01:44,240
What are the four parts of a wave? That's cool. That's amazing. I wish I could be Frantz

8
00:01:44,240 --> 00:01:50,240
Harari. Why? Because then I could make that bright red sun disappear. Look at the sunset.

9
00:01:50,240 --> 00:01:59,240
It's so red it looks like a ball of fire. Yeah. Ladies and gentlemen, I'm about to perform

10
00:01:59,240 --> 00:02:05,240
the most amazing trick. What's with him? I bet he thinks he's a magician. Watch closely.

11
00:02:05,240 --> 00:02:11,240
Before your very own eyes, I will make this coin disappear. Okay, Frantz, I've got to

12
00:02:11,240 --> 00:02:19,240
see this one. Abracadabra, make this coin disappear. Gone. Where did it go? It went

13
00:02:19,240 --> 00:02:25,240
up his sleeve. It did not. It's magic. Then make us disappear because that sunset is blinding.

14
00:02:25,240 --> 00:02:33,240
Yeah. But no one's here. The magician is here. Jacob. I'm starting to get this magic

15
00:02:33,240 --> 00:02:40,240
stuff down. Welcome to Kids Science News Network's morning show, Get Out of Bed. You're Going

16
00:02:40,240 --> 00:02:49,240
to be Late. I'm Ted Toon. This morning's top KSNN story, Red Skies, Warning or Delight?

17
00:02:50,240 --> 00:02:56,240
We go now to I Am Listening with a live report. Thanks, Ted. I'm here with Captain Mac Arell

18
00:02:56,240 --> 00:03:03,240
of the cargo ship Dawn's Early Light. Now, Captain, the saying goes, red skies at night,

19
00:03:03,240 --> 00:03:09,240
sailors delight. Red skies and warnings, sailors take warning. Are you delighted or worried?

20
00:03:09,240 --> 00:03:17,240
I just don't know. It's supposed to be one or the other. I'm so confused. Well, Ted,

21
00:03:17,240 --> 00:03:22,240
it looks like we may never know. Back to you. Thanks for that illuminating report,

22
00:03:22,240 --> 00:03:28,240
I Am. So far, no one has been able to explain the mystery of the red skies over the area.

23
00:03:28,240 --> 00:03:35,240
Stay tuned to KSNN for more information. Last night, we noticed that the sunset was a deep,

24
00:03:35,240 --> 00:03:41,240
deep red. I know. Maybe there's a fire around here and we're seeing a reflection in the

25
00:03:41,240 --> 00:03:47,240
sky. This looks like a case for us to solve. I can see the headlines now. The Treehouse

26
00:03:47,240 --> 00:03:54,240
detectives solved the case of the mysterious red light with magic. Jacob, give it up. Give

27
00:03:54,240 --> 00:04:00,240
what up? He's up to his magic tricks. Yeah, I saw some of them yesterday. Where can we

28
00:04:00,240 --> 00:04:05,240
start our investigation? With the NASA Wi-Fi's investigation log sheet. It's great. You should

29
00:04:05,240 --> 00:04:10,240
really use it in your investigation. Go to the NASA Wi-Fi's website, then click on the

30
00:04:10,240 --> 00:04:15,240
Treehouse, then click on the tool selection. Now click on the investigation log sheet and

31
00:04:15,240 --> 00:04:21,240
print it out. Hey, there's Dr. D. Maybe he can give us a list of experts. This is all

32
00:04:21,240 --> 00:04:29,240
part of science's inquiry. There I am. What are you doing? Just an experiment that didn't

33
00:04:29,240 --> 00:04:44,240
work very well. I'll show you an experiment that will work. Watch this. That's magic.

34
00:04:44,240 --> 00:04:49,240
No, not magic. It's just good science. If I poke the skewer through this end, where

35
00:04:49,240 --> 00:04:53,240
it's not stretched very much, and take it out through the tip, where it's also not stretched,

36
00:04:53,240 --> 00:04:59,240
it won't burst. But if I poke it in the side like this... It would pop. That's because

37
00:04:59,240 --> 00:05:04,240
it's being stretched too tight. That's great. Dr. D., have you noticed the red sunrises

38
00:05:04,240 --> 00:05:09,240
and sunsets? Yes, I have. I just watched a report on it on KSNN. We decided this is a

39
00:05:09,240 --> 00:05:13,240
case for the Treehouse Detectives. We want to know what's making the sunrises and sunsets

40
00:05:13,240 --> 00:05:17,240
so red. The Treehouse Detectives have solved a lot of problems. Think back, where do you

41
00:05:17,240 --> 00:05:22,240
usually begin? In the treehouse. Yes, that's correct. But it's a tool you always use in

42
00:05:22,240 --> 00:05:27,240
your investigations. I know it. It's a scientific method. Yes, again. Remember, this is a tool

43
00:05:27,240 --> 00:05:32,240
you can use every day. We know our problem. I wrote it down in our investigation log.

44
00:05:32,240 --> 00:05:37,240
Why are the sunrises and sunsets so red? All right, you have your problem. What comes next?

45
00:05:37,240 --> 00:05:42,240
Probably research, since we don't know much about the problem. Research means asking a

46
00:05:42,240 --> 00:05:47,240
lot of questions, making observations, and talking to a lot of experts. That's correct.

47
00:05:47,240 --> 00:05:52,240
Remember, it's a scientific method. You research the problem, form a hypothesis, and then test

48
00:05:52,240 --> 00:05:57,240
the hypothesis. It's not always easy. We knew that for a fact. In our past cases, we tested

49
00:05:57,240 --> 00:06:01,240
our hypothesis by experimenting and collecting data. I think you're ready to tackle the sunset

50
00:06:01,240 --> 00:06:09,240
problem now. Thanks, Dr. D. I'm sure we'll be back. Let's see, what would make the sunsets

51
00:06:09,240 --> 00:06:15,240
so red? Red's a color. And the sun gives the earth light. But why would the light from

52
00:06:15,240 --> 00:06:20,240
the sun be a deeper red now? I don't know, but I think we need to do research on light.

53
00:06:20,240 --> 00:06:25,240
Yeah, because I think light has colors in it. I'm doing an internet search on light.

54
00:06:25,240 --> 00:06:32,240
Maybe we can find a museum that has an exhibit on light. I'm typing the keywords science,

55
00:06:32,240 --> 00:06:40,240
museum, and light into the search engine. There are a lot of museums listed. Here's

56
00:06:40,240 --> 00:06:45,240
one in Boston. It's called the Boston Museum of Science. It looks really cool. PJ and his

57
00:06:45,240 --> 00:06:50,240
parents are in Boston. I'll send him an email and tell him to take a trip to the museum.

58
00:06:50,240 --> 00:06:54,240
I hope he remembers to take the investigation log sheet. If you go on a field trip of your

59
00:06:54,240 --> 00:06:58,240
own, this is a great worksheet to take with you to record all of your information.

60
00:07:02,240 --> 00:07:08,240
That's weird. When I look on top of the mural, I can't see anything. Then, when I look at

61
00:07:08,240 --> 00:07:11,240
the filter, I can see everything. Why is that?

62
00:07:11,240 --> 00:07:16,240
It's because of polarization. Welcome to the Boston Museum of Science. My name is Michael

63
00:07:16,240 --> 00:07:19,240
Sheese, and I'm in charge of the museum's physical science program.

64
00:07:19,240 --> 00:07:24,240
Hi, Mr. Sheese. I'm PJ. Well, you see, the TRIOS detective sent me an email, and they

65
00:07:24,240 --> 00:07:28,240
said that coming here would be a great place to learn more about light. So here I am.

66
00:07:28,240 --> 00:07:32,240
You've got a great exhibit on light and objects called Lighthouse. What exactly would you

67
00:07:32,240 --> 00:07:36,240
like to know about light? Well, I think I should understand what exactly

68
00:07:36,240 --> 00:07:40,240
is light. I've got a great place to start. Okay, great.

69
00:07:43,240 --> 00:07:47,240
All light is energy. Do you know what the main source of energy is here on Earth?

70
00:07:47,240 --> 00:07:51,240
The sun? That's exactly right. The sun is a natural

71
00:07:51,240 --> 00:07:57,240
source of energy. Light can be either artificial or natural. What might be an example of an

72
00:07:57,240 --> 00:08:00,240
artificial source? Would that be something like a light bulb?

73
00:08:00,240 --> 00:08:03,240
That's right. In fact, I happen to have one right here. Cool.

74
00:08:03,240 --> 00:08:07,240
Let's go. Okay. Is light the same whether it's artificial

75
00:08:07,240 --> 00:08:11,240
or natural? All light is made up of photons.

76
00:08:11,240 --> 00:08:15,240
We learned about photons in our electricity mystery. And did you learn about atoms, too?

77
00:08:15,240 --> 00:08:19,240
Yes, we did. There are three different parts, protons, neutrons, and electrons.

78
00:08:19,240 --> 00:08:23,240
That's right. The electrons that make up light are unstable, and from time to time, they

79
00:08:23,240 --> 00:08:27,240
absorb energy. One of the ways the atom gets rid of this energy is it releases it in a

80
00:08:27,240 --> 00:08:31,240
bundle of light called a photon. Are there different kinds of photons?

81
00:08:31,240 --> 00:08:35,240
Yes. The amount of energy that's in the photon determines what kind of light wave is

82
00:08:35,240 --> 00:08:39,240
produced. Wait a minute.

83
00:08:39,240 --> 00:08:43,240
Light is a wave? That's right. In fact, I've got a demonstration of it right here.

84
00:08:43,240 --> 00:08:47,240
I'm going to hold on to my end of the rope. I'd like you to take the other end of the rope.

85
00:08:47,240 --> 00:08:51,240
And if you could wiggle it back and forth, we can demonstrate what a light wave

86
00:08:51,240 --> 00:08:55,240
might look like. Light coming from the sun takes

87
00:08:55,240 --> 00:08:59,240
eight minutes to reach us, and that's 98 million miles away.

88
00:08:59,240 --> 00:09:03,240
Whoa, that's fast! As you can see here, light travels in a straight line

89
00:09:03,240 --> 00:09:07,240
called a ray. Yes, but then when I put the light on the prism, the light bends.

90
00:09:07,240 --> 00:09:11,240
That's right. Light won't travel in a straight line unless it hits something

91
00:09:11,240 --> 00:09:15,240
and becomes obstructed. Oh, I think I understand.

92
00:09:15,240 --> 00:09:19,240
Why don't you take some time and explore some of our other exhibits on lightenopolis?

93
00:09:19,240 --> 00:09:23,240
Thanks. I saw some great exhibits that I want to go to. Great. Bye.

94
00:09:23,240 --> 00:09:27,240
See ya. Wow, this is so weird. I can't grab this

95
00:09:27,240 --> 00:09:31,240
ring. This is just like what I saw on the Franz Harari's magic show.

96
00:09:31,240 --> 00:09:35,240
Man!

97
00:09:35,240 --> 00:09:39,240
Am I seeing things? And for my final light exhibit, I can

98
00:09:39,240 --> 00:09:43,240
create my own picture by waving the wand.

99
00:09:43,240 --> 00:09:47,240
Wow, the sunrise this morning was even

100
00:09:47,240 --> 00:09:51,240
better than the one yesterday. I read PJ's investigation log online

101
00:09:51,240 --> 00:09:55,240
and his notes on the Boston Science Museum are great. Hey guys.

102
00:09:55,240 --> 00:09:59,240
Hi. You really missed out on a fantastic trip. Look what I brought back. It's called a prism.

103
00:09:59,240 --> 00:10:03,240
Ooh, let me see it. I learned at the Boston Museum of Science

104
00:10:03,240 --> 00:10:07,240
that light travels in waves and it's also a ray. But we learned in math

105
00:10:07,240 --> 00:10:11,240
class that a ray is a straight line. How can light travel in waves and be a

106
00:10:11,240 --> 00:10:15,240
straight line? What do we know? We know that there have been bright red

107
00:10:15,240 --> 00:10:19,240
sunsets and sunrises. We know that light travels in a

108
00:10:19,240 --> 00:10:23,240
wave. What do we need to know? We need to find out how light can

109
00:10:23,240 --> 00:10:27,240
travel in waves and a straight line. Where can we go? NASA

110
00:10:27,240 --> 00:10:31,240
Langley Research Center is probably the best place to start. I knew you'd say that, but

111
00:10:31,240 --> 00:10:35,240
it's so true. To do flight research, you have to study a lot of different things in the sky.

112
00:10:39,240 --> 00:10:43,240
Hi. My name is Clayton Turner. I'm a research engineer here at NASA Langley Research

113
00:10:43,240 --> 00:10:47,240
Center. Hi. I'm Kaylee. I'm Catherine. Nice to meet you.

114
00:10:47,240 --> 00:10:51,240
We're trying to solve a problem, and we need to know how light can travel in a wave and a

115
00:10:51,240 --> 00:10:55,240
straight line at the very same time. Perhaps I can help. I do a lot of research with

116
00:10:55,240 --> 00:10:59,240
light on this laboratory. That doesn't look like a laboratory. That looks like

117
00:10:59,240 --> 00:11:03,240
a plane. Well, this is NASA Langley's 757 Ares Research Aircraft.

118
00:11:03,240 --> 00:11:07,240
Come on board. Do you fly this

119
00:11:07,240 --> 00:11:11,240
plane? No, I don't fly the plane. We use this plane to conduct research.

120
00:11:11,240 --> 00:11:15,240
In particular, we use light to study the atmosphere. What's that?

121
00:11:15,240 --> 00:11:19,240
This is a spectrometer. Let's go in the back, and I'll tell you a little bit more about it.

122
00:11:19,240 --> 00:11:23,240
This is a spectrometer. It collects light and sorts it by wavelength.

123
00:11:23,240 --> 00:11:27,240
Can you tell us more about light as a wave and a straight line? Yes.

124
00:11:27,240 --> 00:11:31,240
Light can be thought of as particles called photons that travel in a wave-like pattern.

125
00:11:31,240 --> 00:11:35,240
But we also learned that light can travel in a ray, which is a straight line.

126
00:11:35,240 --> 00:11:39,240
Yes. A simple model of light is called a ray or a straight line.

127
00:11:39,240 --> 00:11:43,240
A ray at the end of the line shows the direction that the photon is traveling in.

128
00:11:43,240 --> 00:11:47,240
But what about a wave? Light, or electromagnetic radiation,

129
00:11:47,240 --> 00:11:51,240
is a form of energy called gradient energy that has an electric field

130
00:11:51,240 --> 00:11:55,240
and a magnetic field. If you take the simple model shown on the screen

131
00:11:55,240 --> 00:11:59,240
and add an electric field, it would look like this. That looks funny.

132
00:11:59,240 --> 00:12:03,240
Look at the ends of the electric field. It looks kind of like a

133
00:12:03,240 --> 00:12:07,240
wave. But why are the lines different heights? First, let's

134
00:12:07,240 --> 00:12:11,240
look at a model of the wave. He knows magic, too!

135
00:12:11,240 --> 00:12:15,240
The top of the wave is called a crest. The bottom of the wave is called

136
00:12:15,240 --> 00:12:19,240
a trough. The wavelength is measured from the top of one crest to the top

137
00:12:19,240 --> 00:12:23,240
of the next crest. Do different wavelengths mean different things? Yes.

138
00:12:23,240 --> 00:12:27,240
Color is typically described by the wavelength of frequency. For visible

139
00:12:27,240 --> 00:12:31,240
light, violet has the shortest wavelength and red has the longest.

140
00:12:31,240 --> 00:12:35,240
So what is frequency? Frequency is the number of times the crest of the

141
00:12:35,240 --> 00:12:39,240
wave passes a stationary point. I get it! So the shorter the wavelength,

142
00:12:39,240 --> 00:12:43,240
the more waves would pass a stationary point, and that would be high frequency.

143
00:12:43,240 --> 00:12:47,240
So violet is high frequency, and red is low frequency.

144
00:12:47,240 --> 00:12:51,240
Is there anything else we should know about a wave? Yes, amplitude.

145
00:12:51,240 --> 00:12:55,240
Why is this important? The amplitude is half the distance from the crest to the

146
00:12:55,240 --> 00:12:59,240
trough. The higher the amplitude and frequency, the higher the energy.

147
00:12:59,240 --> 00:13:03,240
Thanks for letting us go on the 757. We learned a lot.

148
00:13:03,240 --> 00:13:07,240
I really hope this information helps you solve your problem.

149
00:13:07,240 --> 00:13:11,240
So what's our hypothesis? I think it should be that there are low frequency

150
00:13:11,240 --> 00:13:15,240
waves in the sky. That makes the sky red.

151
00:13:15,240 --> 00:13:19,240
I'll write this hypothesis in our investigation log. I guess that makes sense.

152
00:13:19,240 --> 00:13:23,240
I don't know what could be causing the low frequency waves, though.

153
00:13:23,240 --> 00:13:27,240
I think we should do a little research. Remember, in our past cases, our hypothesis

154
00:13:27,240 --> 00:13:31,240
hasn't always been correct.

155
00:13:31,240 --> 00:13:35,240
What's up? Will the Treehouse Detectives find out what's causing the red sunrises

156
00:13:35,240 --> 00:13:39,240
and sunsets? Could there be something causing low frequency waves in the sky?

157
00:13:39,240 --> 00:13:43,240
Stay tuned for more of The Case of the Mysterious Red Light.

158
00:13:53,240 --> 00:13:57,240
The Treehouse Detectives still need your help.

159
00:13:57,240 --> 00:14:01,240
Find answers to the following questions to solve the mystery.

160
00:14:01,240 --> 00:14:05,240
How does light refract and reflect?

161
00:14:05,240 --> 00:14:09,240
Find examples of translucent, transparent,

162
00:14:09,240 --> 00:14:13,240
and opaque.

163
00:14:13,240 --> 00:14:17,240
Why is the sky blue?

164
00:14:17,240 --> 00:14:21,240
What's that spot on my clothes? Where'd it go? It disappeared.

165
00:14:21,240 --> 00:14:25,240
There it is on the wall. How did it get over there? With my mirror.

166
00:14:25,240 --> 00:14:29,240
When the light hits the mirror, it bounces around the room. Light can bounce?

167
00:14:29,240 --> 00:14:33,240
I'm confused. I thought we learned from Mr. Turner that light travels in a ray.

168
00:14:33,240 --> 00:14:37,240
This isn't doing that.

169
00:14:37,240 --> 00:14:41,240
We need to find out, because there could be low frequency waves bouncing around the sky.

170
00:14:41,240 --> 00:14:45,240
Where should we go? I classroomed on a field trip to the Jefferson Lab in Newport News, Virginia.

171
00:14:45,240 --> 00:14:49,240
They do a lot of research there. Let's get up and go.

172
00:14:49,240 --> 00:14:53,240
Hi.

173
00:14:53,240 --> 00:14:57,240
I'm Michelle Shin. Welcome to the Department of Energy's Jefferson Lab.

174
00:14:57,240 --> 00:15:01,240
Hi, Dr. Shin. This is a neat-looking place. What do you do here?

175
00:15:01,240 --> 00:15:05,240
Well, I'm a laser physicist. That's a scientist who studies

176
00:15:05,240 --> 00:15:09,240
and makes different kinds of lasers and uses them to hit different objects.

177
00:15:09,240 --> 00:15:13,240
Lasers? Like in Star Wars? Well, sort of like that.

178
00:15:13,240 --> 00:15:17,240
So anyway, what can I help you with today?

179
00:15:17,240 --> 00:15:21,240
I was using mirrors this morning and noticed a light bounced around the room.

180
00:15:21,240 --> 00:15:25,240
We want to know more about how light bounces.

181
00:15:25,240 --> 00:15:29,240
Well, I'd be happy to answer that for you, Bianca.

182
00:15:29,240 --> 00:15:33,240
Light that bounces off a surface is called reflective light.

183
00:15:33,240 --> 00:15:37,240
The type of surface determines the kind of reflection you get.

184
00:15:37,240 --> 00:15:41,240
A mirror is really shiny. Does that make a difference?

185
00:15:41,240 --> 00:15:45,240
It makes a big difference. If the surface is shiny, then the image you see looks just like the object.

186
00:15:45,240 --> 00:15:49,240
Does light scatter light? That's right. You catch on really fast.

187
00:15:49,240 --> 00:15:53,240
Does light only reflect? No. Light also refracts.

188
00:15:53,240 --> 00:15:57,240
What does refractive mean? Well, Bianca, I think it's easiest to show you.

189
00:15:57,240 --> 00:16:01,240
Okay, Bianca, we need to put on some gloves and goggles because you're going to work with some liquid nitrogen.

190
00:16:01,240 --> 00:16:05,240
We use these in science. Good. It helps to be safe

191
00:16:05,240 --> 00:16:09,240
when you're doing experiments. What's that stuff bubbling?

192
00:16:09,240 --> 00:16:13,240
It's liquid nitrogen. We're going to use the vapor to explore reflection and refraction.

193
00:16:13,240 --> 00:16:17,240
So, Bianca, this is a laser, and I'm going to shine it on the gelatin.

194
00:16:17,240 --> 00:16:21,240
But first, I need to have you dim the lights.

195
00:16:21,240 --> 00:16:25,240
What I'm going to do now is shine it on the gelatin. Look closely and tell me what you see.

196
00:16:25,240 --> 00:16:29,240
I see the light coming off into the gelatin. That must be reflection.

197
00:16:29,240 --> 00:16:33,240
Right. But the light is also being bent. Why is that?

198
00:16:33,240 --> 00:16:37,240
Well, when light travels from one medium, such as air,

199
00:16:37,240 --> 00:16:41,240
to another medium, such as gelatin, its speed changes.

200
00:16:41,240 --> 00:16:45,240
And when the speed changes, the light bends, and we call that light refraction.

201
00:16:45,240 --> 00:16:49,240
Does the speed of light speed up or slow down when it's going through the gelatin?

202
00:16:49,240 --> 00:16:53,240
Well, because the gelatin is thicker than air, it slows down.

203
00:16:53,240 --> 00:16:57,240
I wonder if magicians create some of their magic with mirrors.

204
00:16:57,240 --> 00:17:01,240
This is a concave mirror. It curves inwards, and you can see that your image,

205
00:17:01,240 --> 00:17:05,240
if I hold it in one way, is upright, and as I get closer,

206
00:17:05,240 --> 00:17:09,240
it gets inverted. It turns upside down. That'd be an easy way to stand on your head.

207
00:17:09,240 --> 00:17:13,240
It really would. This is a convex lens.

208
00:17:13,240 --> 00:17:17,240
You can see that the surface curves outwards, and as you look at it,

209
00:17:17,240 --> 00:17:21,240
you look much smaller. And another place that uses lenses and mirrors is NASA.

210
00:17:21,240 --> 00:17:25,240
NASA needs mirrors and lenses for their big telescopes,

211
00:17:25,240 --> 00:17:29,240
space telescopes like the Hubble Telescope,

212
00:17:29,240 --> 00:17:33,240
or the Mars Global Surveyor, or the GOES weather satellites.

213
00:17:33,240 --> 00:17:37,240
That's cool. Thanks, Dr. Shin.

214
00:17:37,240 --> 00:17:41,240
Bye.

215
00:17:41,240 --> 00:17:45,240
I wonder if the illusionist, Franz Harari, uses mirrors to make things disappear.

216
00:17:45,240 --> 00:17:49,240
Maybe he uses light mirrors, like he'd ever tell us his secrets.

217
00:17:49,240 --> 00:17:53,240
I'm never telling him mine. Maybe we should go to Franz's website

218
00:17:53,240 --> 00:17:57,240
to find out more about him. Oh, look, he's doing a live chat.

219
00:17:57,240 --> 00:18:01,240
Just click here and we can talk to him. Hi, Franz.

220
00:18:01,240 --> 00:18:05,240
Oh, hey there. Who are you? We are the Treehouse Detectives,

221
00:18:05,240 --> 00:18:09,240
and we know how you make things disappear.

222
00:18:09,240 --> 00:18:13,240
Detectives? You're going to love this. I'm sitting in the cockpit of NASA 747.

223
00:18:13,240 --> 00:18:17,240
Now, check this out. This is actually the official shuttle carrier aircraft.

224
00:18:17,240 --> 00:18:21,240
It's what NASA uses to move the space shuttle from one city to the other

225
00:18:21,240 --> 00:18:25,240
when it's not in space. I mean, right now,

226
00:18:25,240 --> 00:18:29,240
we're parked at NASA Dryden Flight Research Center.

227
00:18:29,240 --> 00:18:33,240
And I was here because I was checking out this airplane they have.

228
00:18:33,240 --> 00:18:37,240
And I'm thinking I'd like to make it disappear. You can do that?

229
00:18:37,240 --> 00:18:41,240
Well, I'm not going to give you all my secrets, but if you want,

230
00:18:41,240 --> 00:18:45,240
come on out and check it out for yourself. Yeah, right. How are we going to get to NASA Dryden?

231
00:18:45,240 --> 00:18:49,240
It's easier than you think. Check out your keyboard there.

232
00:18:49,240 --> 00:18:53,240
You see that? There's one button you haven't used yet. Right over there.

233
00:18:53,240 --> 00:18:57,240
This one right here.

234
00:18:57,240 --> 00:19:01,240
Wow!

235
00:19:01,240 --> 00:19:05,240
We really made it. I can't believe he really

236
00:19:05,240 --> 00:19:09,240
got us to California. Where's Franz?

237
00:19:09,240 --> 00:19:13,240
Hey, kids. Welcome to NASA. How was your trip?

238
00:19:13,240 --> 00:19:17,240
Where is he? Look, he's up there.

239
00:19:17,240 --> 00:19:21,240
Our trip was pretty wild, but I liked it.

240
00:19:21,240 --> 00:19:25,240
Whoa. I really

241
00:19:25,240 --> 00:19:29,240
like magic stuff. How did you get down here?

242
00:19:29,240 --> 00:19:33,240
Well, you know, at NASA, anything's possible.

243
00:19:33,240 --> 00:19:37,240
Now, how can I help you guys? We're

244
00:19:37,240 --> 00:19:41,240
investigating a problem that deals with the properties of light.

245
00:19:41,240 --> 00:19:45,240
I'm a big fan of yours, and I think you use light to help things disappear.

246
00:19:45,240 --> 00:19:49,240
Well, to be honest, in my business, light is everything.

247
00:19:49,240 --> 00:19:53,240
Now, I'm not going to give you all my secrets, but come on, show me something cool.

248
00:19:53,240 --> 00:19:57,240
Alright.

249
00:19:57,240 --> 00:20:01,240
I'm sort of all set up to do a little demonstration here.

250
00:20:01,240 --> 00:20:05,240
Now, here's a little model of an SR-71 Blackbird. This is like my favorite plane.

251
00:20:05,240 --> 00:20:09,240
It's so cool. This plane, the real plane, can actually go from New York

252
00:20:09,240 --> 00:20:13,240
to Los Angeles in like an hour. It's amazing. Now, you see the model,

253
00:20:13,240 --> 00:20:17,240
but the reason that you see this model is because light is hitting the model

254
00:20:17,240 --> 00:20:21,240
and then bouncing back and hitting your eyes. And your eyes are telling

255
00:20:21,240 --> 00:20:25,240
your brain that this little airplane is actually there. Imagine this.

256
00:20:25,240 --> 00:20:29,240
Imagine that we put just a reflection of my hand in there.

257
00:20:29,240 --> 00:20:33,240
Well, we've seen that a bunch of times, but now you add another hand

258
00:20:33,240 --> 00:20:37,240
and now you go into kind of a symmetrical world, and watch this.

259
00:20:37,240 --> 00:20:41,240
Your brain almost tells you the reflection

260
00:20:41,240 --> 00:20:45,240
of the hand is the real hand. See that? Pretty cool, huh?

261
00:20:45,240 --> 00:20:49,240
That's where it gets really magical. Now, I was telling you about my little

262
00:20:49,240 --> 00:20:53,240
model here, the SR-71. Let's see if we can't do some real magic with it.

263
00:20:53,240 --> 00:20:57,240
I need some magic words. You got any magic words?

264
00:20:57,240 --> 00:21:01,240
Abracadabra. Abracadabra. That'll work perfect.

265
00:21:01,240 --> 00:21:05,240
And the reflection becomes reality.

266
00:21:05,240 --> 00:21:09,240
And there's one for you,

267
00:21:09,240 --> 00:21:13,240
and one for you. Let's try this trick one more time,

268
00:21:13,240 --> 00:21:17,240
and this time you figure out if you can see how light made it all work, alright?

269
00:21:17,240 --> 00:21:21,240
Alright. Come with me.

270
00:21:21,240 --> 00:21:25,240
I couldn't help but notice you guys both have planes, but I don't have one, but I have an idea.

271
00:21:25,240 --> 00:21:29,240
How would you feel if I borrowed your little model for just a moment?

272
00:21:29,240 --> 00:21:33,240
Cool with that? Alright, I'll tell you what. You guys stand over there.

273
00:21:33,240 --> 00:21:37,240
Don't take your eyes off what's about to happen over here,

274
00:21:37,240 --> 00:21:41,240
because that's where the real magic's about to begin, alright?

275
00:21:41,240 --> 00:21:45,240
We will hold onto this shot until after that SR-71

276
00:21:45,240 --> 00:21:49,240
has disappeared. Gentlemen, raise the tarp.

277
00:21:49,240 --> 00:21:53,240
Alright, check it out.

278
00:21:53,240 --> 00:21:57,240
Wow!

279
00:21:57,240 --> 00:22:01,240
That's it!

280
00:22:01,240 --> 00:22:05,240
How did you do that?

281
00:22:05,240 --> 00:22:09,240
That was amazing. How did you do it? How'd I do it? It's all about light.

282
00:22:09,240 --> 00:22:13,240
I need to make a phone call. Oh, sure. Go for it.

283
00:22:13,240 --> 00:22:17,240
Hi, Dr. D. Hi, guys. What's all that?

284
00:22:17,240 --> 00:22:21,240
Thought I might be able to help you with your light experiments. Where are Jacob and Bianca?

285
00:22:21,240 --> 00:22:25,240
I don't know. They were supposed to meet us here.

286
00:22:25,240 --> 00:22:29,240
Hello? Hi, Dr. D. It's Bianca. We're over at NASA Dryden.

287
00:22:29,240 --> 00:22:33,240
We're running a little late. We'll be there soon.

288
00:22:33,240 --> 00:22:37,240
Where are you? I'll be right there.

289
00:22:37,240 --> 00:22:41,240
Well, you're definitely great at what you do, but we gotta get back home.

290
00:22:41,240 --> 00:22:45,240
Um, well, I have an idea. Go ahead and assume the position.

291
00:22:45,240 --> 00:22:49,240
What? Assume the position. Oh. Yeah, there you go. Ready?

292
00:22:49,240 --> 00:22:53,240
We're sending you home. And when I say go, blink.

293
00:22:53,240 --> 00:22:57,240
You ready? Go.

294
00:22:57,240 --> 00:23:01,240
We made it!

295
00:23:01,240 --> 00:23:05,240
Where's Jacob? I don't know. Franz must have sent him back to his house.

296
00:23:05,240 --> 00:23:09,240
Wow, how did you get here so fast? Just magic. Or is this an illusion?

297
00:23:09,240 --> 00:23:13,240
That was quite a trick. We're learning all about light to try and solve this red sunset problem.

298
00:23:13,240 --> 00:23:17,240
Yeah, I went to the Boston Science Museum.

299
00:23:17,240 --> 00:23:21,240
I learned how light travels in waves and in a straight line.

300
00:23:21,240 --> 00:23:25,240
And we also learned a little bit about mirrors and lenses and about reflection and refraction.

301
00:23:25,240 --> 00:23:29,240
And a little bit of magic, too. Have you learned the difference between transparent, opaque, and translucent yet?

302
00:23:29,240 --> 00:23:33,240
Trans-what? Let me explain.

303
00:23:33,240 --> 00:23:37,240
Light can pass through a transparent object and make an object on the other side clearly visible.

304
00:23:37,240 --> 00:23:41,240
You mean like a window? Yep.

305
00:23:41,240 --> 00:23:45,240
Take a look at this light bulb. By turning the crank, can you see the filament clearly?

306
00:23:45,240 --> 00:23:49,240
Yes, look at that. What else is transparent?

307
00:23:49,240 --> 00:23:53,240
A car's windshield? Exactly. Until it gets all fogged up, and then it's called translucent.

308
00:23:53,240 --> 00:23:57,240
Oh, so translucent means that light can get through, but not just very much.

309
00:23:57,240 --> 00:24:01,240
You're getting very good at this. When an object is translucent, the light is diffused,

310
00:24:01,240 --> 00:24:05,240
and you can't see the object very clearly. That would make it hard to drive.

311
00:24:05,240 --> 00:24:09,240
Now, what does opaque mean? Do you know what that is?

312
00:24:09,240 --> 00:24:13,240
I think it means that no light can get through. When there are solid objects like rock or concrete, that's opaque.

313
00:24:13,240 --> 00:24:17,240
That's correct, but it's much more interesting than that.

314
00:24:17,240 --> 00:24:21,240
Step over there, please.

315
00:24:21,240 --> 00:24:25,240
Look at this example. Here I have two sheets of light-polarizing material. Can you see me clearly?

316
00:24:25,240 --> 00:24:29,240
Yes, it is a little dark, but it's clear, so it's transparent.

317
00:24:29,240 --> 00:24:33,240
And watch what happens when I rotate one of the two sheets.

318
00:24:33,240 --> 00:24:37,240
It's clear, just like magic. It became opaque and went black.

319
00:24:37,240 --> 00:24:41,240
I think I understand translucent, transparent, and opaque now.

320
00:24:41,240 --> 00:24:45,240
The sky is transparent most of the time. Clouds can make the sky opaque.

321
00:24:45,240 --> 00:24:49,240
I wonder if clouds are causing the problem. I don't think it's clouds.

322
00:24:49,240 --> 00:24:53,240
Let's go back to the treehouse and organize all this information. Bye, Dr. D.

323
00:24:53,240 --> 00:24:57,240
Bye, Dr. D. See you.

324
00:24:57,240 --> 00:25:01,240
This one is definitely transparent. And that one's translucent.

325
00:25:01,240 --> 00:25:05,240
Only a little light can shine through.

326
00:25:05,240 --> 00:25:09,240
And that one has to be opaque. There isn't any light getting through.

327
00:25:09,240 --> 00:25:13,240
Dr. D. would give us an A.

328
00:25:13,240 --> 00:25:17,240
On a clear night, the sky looks transparent, but why does it look translucent during the day?

329
00:25:17,240 --> 00:25:21,240
Yes, I wonder why the sky is blue during the day, but red at sunrises and sunsets.

330
00:25:21,240 --> 00:25:25,240
This is all so confusing. Let's go to the problem board and try to figure out what we need to learn next.

331
00:25:25,240 --> 00:25:29,240
We know the sky is still a bright red.

332
00:25:29,240 --> 00:25:33,240
And now we know that light can be refracted and reflected.

333
00:25:33,240 --> 00:25:37,240
Maybe if we knew what causes the color of the sky to be blue during the day,

334
00:25:37,240 --> 00:25:41,240
it would help us to find out why the sky is red at sunrise and sunset.

335
00:25:41,240 --> 00:25:45,240
I think the night sky is transparent and the day sky is translucent.

336
00:25:45,240 --> 00:25:49,240
That's true. What makes the sky different?

337
00:25:49,240 --> 00:25:53,240
One variable between the night sky and the sky during the day is the sun.

338
00:25:53,240 --> 00:25:57,240
I think we need to learn more about the sun.

339
00:25:57,240 --> 00:26:01,240
Let's call NASA Ames in Mountain View, California. They have an expert in the sun.

340
00:26:01,240 --> 00:26:05,240
Hi, kids. I'm Peter Poluski at NASA Ames Research Center.

341
00:26:05,240 --> 00:26:09,240
I study light in the Earth's atmosphere. What can I do for you today?

342
00:26:09,240 --> 00:26:13,240
We're trying to figure out a problem, and we need to know why the skies are blue during the day.

343
00:26:13,240 --> 00:26:17,240
Good question. Let me first talk to you about the sun.

344
00:26:17,240 --> 00:26:21,240
It's white light, which means it's really a mixture of all colors of the spectrum from blue to red.

345
00:26:21,240 --> 00:26:25,240
If the sunlight is white, then why is the sky blue?

346
00:26:25,240 --> 00:26:29,240
We learned about reflection at the Jefferson Lab.

347
00:26:29,240 --> 00:26:33,240
Could the sky be blue because it's reflecting blue off the ocean?

348
00:26:33,240 --> 00:26:37,240
No, that's a common misconception. The Earth has an atmosphere,

349
00:26:37,240 --> 00:26:41,240
which is made up of molecules such as oxygen and nitrogen.

350
00:26:41,240 --> 00:26:45,240
It's also made up of tiny little microscopic particles,

351
00:26:45,240 --> 00:26:49,240
and these tiny little microscopic particles in the atmosphere are called aerosols.

352
00:26:49,240 --> 00:26:53,240
I don't see anything in the air.

353
00:26:53,240 --> 00:26:57,240
We learned at the Boston Museum of Science that light is a wave and that it is made up of photons.

354
00:26:57,240 --> 00:27:01,240
Occasionally, the photons will actually bounce off of the molecules and particles

355
00:27:01,240 --> 00:27:05,240
and go off into different directions. That's something that we call scattering.

356
00:27:05,240 --> 00:27:09,240
Let me show you an experiment I have set up here.

357
00:27:09,240 --> 00:27:13,240
This fancy instrument is something we call a sun simulator,

358
00:27:13,240 --> 00:27:17,240
but really it's just a lamp which sort of mimics the output of the sun.

359
00:27:17,240 --> 00:27:21,240
First of all, you can see the beaker here has very little light

360
00:27:21,240 --> 00:27:25,240
scattering out of the sides of it.

361
00:27:25,240 --> 00:27:29,240
Now watch what happens when I add some milk to the beaker.

362
00:27:29,240 --> 00:27:33,240
What does the milk represent?

363
00:27:33,240 --> 00:27:37,240
Some molecules and particles in the atmosphere.

364
00:27:37,240 --> 00:27:41,240
Now we've got plenty of light scattered out the sides, and notice it's very bluish.

365
00:27:41,240 --> 00:27:45,240
When we look at the sun beam that's been transmitted through the beaker, however, that's become red.

366
00:27:45,240 --> 00:27:49,240
That's because the blue light's been removed from the beam and scattered out the sides.

367
00:27:49,240 --> 00:27:53,240
The blue light is a mixture of all colors.

368
00:27:53,240 --> 00:27:57,240
Now the blue photons will actually scatter off of the particles much more frequently than the red ones.

369
00:27:57,240 --> 00:28:01,240
That means that we get blue light scattered out and the red light gets transmitted through.

370
00:28:01,240 --> 00:28:05,240
So why do we see red skies at night and in the morning?

371
00:28:05,240 --> 00:28:09,240
Well, when the sun's near the horizon, the sun beam is traveling through a very, very thick portion of the atmosphere.

372
00:28:09,240 --> 00:28:13,240
That's also where most of the particles are concentrated

373
00:28:13,240 --> 00:28:17,240
because gravity keeps the particles near the ground.

374
00:28:17,240 --> 00:28:21,240
Any event that puts more particles near the horizon can make the sunset and sunrise even more red than it is usually.

375
00:28:21,240 --> 00:28:25,240
Now, one of those events is a pollution event.

376
00:28:25,240 --> 00:28:29,240
I'm not an expert in pollution, but I happen to know one.

377
00:28:29,240 --> 00:28:33,240
His name is Mark, and he works at the Langley Research Center.

378
00:28:33,240 --> 00:28:37,240
So why don't we give him a call?

379
00:28:37,240 --> 00:28:41,240
This is so cool. Wow, looks like we found the right place.

380
00:28:41,240 --> 00:28:45,240
Hello, Mr. Vaughn. Hey, guys.

381
00:28:45,240 --> 00:28:49,240
When we think about air pollution, we think about the things that human beings put into the air.

382
00:28:49,240 --> 00:28:53,240
We think about the emissions from factory smokestacks.

383
00:28:53,240 --> 00:28:57,240
They're thinking about the exhaust from automobiles.

384
00:28:57,240 --> 00:29:01,240
But when we actually get down to measuring the aerosol content in the air,

385
00:29:01,240 --> 00:29:05,240
we find out that human beings account for only about 10% of it.

386
00:29:05,240 --> 00:29:09,240
The other 90% comes from Mother Nature herself.

387
00:29:09,240 --> 00:29:13,240
Mother Nature? But I always thought that nature was clean and natural.

388
00:29:13,240 --> 00:29:17,240
It also spits blistering hot gases way, way, way up.

389
00:29:17,240 --> 00:29:21,240
And those gases react with water vapor to form little tiny

390
00:29:21,240 --> 00:29:25,240
sulfuric acid droplets that can hang around in the stratosphere for years.

391
00:29:25,240 --> 00:29:29,240
But think about big dust storms coming across the desert.

392
00:29:29,240 --> 00:29:33,240
How do you know how much dirt is in the air?

393
00:29:33,240 --> 00:29:37,240
Matthew, you'd be a cloud with a squirt bottle.

394
00:29:37,240 --> 00:29:41,240
PJ, you were going to be a lidar with a laser, and I'm going to stand here

395
00:29:41,240 --> 00:29:45,240
and allow her to be a dust storm.

396
00:29:45,240 --> 00:29:49,240
Wow, they look like sparkles. You bet they do.

397
00:29:49,240 --> 00:29:53,240
We use a very similar technique when we measure real aerosols in the atmosphere.

398
00:29:53,240 --> 00:29:57,240
Only there we use a machine called a lidar.

399
00:29:57,240 --> 00:30:01,240
Come on, I've got one right over here I can show you.

400
00:30:01,240 --> 00:30:05,240
Wow, that's a big machine. What does it do?

401
00:30:05,240 --> 00:30:09,240
What we do is fire pulses of laser light out of the laser

402
00:30:09,240 --> 00:30:13,240
mirror here. From there, they shoot straight up into the atmosphere.

403
00:30:13,240 --> 00:30:17,240
They beam out, and just like we saw the sparkles off of aerosols in our

404
00:30:17,240 --> 00:30:21,240
little experiment, we use our telescope to look at the sparkles

405
00:30:21,240 --> 00:30:25,240
off of real aerosols in the atmosphere. Could the aerosols from

406
00:30:25,240 --> 00:30:29,240
pollution cause the sky to turn red during sunrises and sunsets?

407
00:30:29,240 --> 00:30:33,240
Sure, sure they can. Circumstances are right.

408
00:30:33,240 --> 00:30:37,240
We learned from Dr. Poluski that aerosols scatter more blue photons and leave the red ones

409
00:30:37,240 --> 00:30:41,240
less to see. Oh, absolutely. If you increase the number of small particles

410
00:30:41,240 --> 00:30:45,240
up there, they will scatter away more blue light, and you will see more red.

411
00:30:45,240 --> 00:30:49,240
Thank you, we learned a lot. Good. Thanks.

412
00:30:49,240 --> 00:30:53,240
Good luck on your project. Bye. Bye.

413
00:30:53,240 --> 00:30:57,240
Well, I think we need a new hypothesis. Especially since we just learned how pollution can turn the sky

414
00:30:57,240 --> 00:31:01,240
red. I mean, our hypothesis wasn't wrong, but it didn't explain where the low frequency

415
00:31:01,240 --> 00:31:05,240
waves came from. A stronger hypothesis would be if the sky is red, then there's

416
00:31:05,240 --> 00:31:09,240
got to be pollution in it. Yes, but the hard part is going to be to figure out where the

417
00:31:09,240 --> 00:31:13,240
pollution is coming from. I know we'll figure it out.

418
00:31:13,240 --> 00:31:17,240
What's up? Is light being reflected or refracted? Can air

419
00:31:17,240 --> 00:31:21,240
pollution be causing the problem? Are there any other variables that have changed

420
00:31:21,240 --> 00:31:25,240
to make the sunsets and sunrises so red? If so, what could they

421
00:31:25,240 --> 00:31:29,240
be? Stay with us next time for the next chapter of the case of the

422
00:31:29,240 --> 00:31:33,240
mysterious red light.

423
00:31:35,240 --> 00:31:39,240
You're getting very close

424
00:31:39,240 --> 00:31:43,240
to solving the mystery. Stay sharp and look for answers to

425
00:31:43,240 --> 00:31:47,240
these questions. What does the electromagnetic

426
00:31:47,240 --> 00:31:51,240
spectrum contain? How are volcanoes

427
00:31:51,240 --> 00:31:55,240
different from one another? What is the ring

428
00:31:55,240 --> 00:31:59,240
of fire?

429
00:31:59,240 --> 00:32:03,240
That was so neat. I love all the colors in a rainbow. How many colors

430
00:32:03,240 --> 00:32:07,240
are there in a rainbow? I don't know. Let's ask Dr. D. How many colors

431
00:32:07,240 --> 00:32:11,240
do you think are in a rainbow? It's a guy's name.

432
00:32:11,240 --> 00:32:15,240
To know the colors in a rainbow, all you have to do is know the guy's name.

433
00:32:15,240 --> 00:32:19,240
That would be seven colors. Let's use PJ's present from the Boston Science

434
00:32:19,240 --> 00:32:23,240
Museum. Look at the colors of the rainbow.

435
00:32:23,240 --> 00:32:27,240
Let's count them. I see red and orange.

436
00:32:27,240 --> 00:32:31,240
And there's yellow and green. Blue is really clear, but the colors on the end are

437
00:32:31,240 --> 00:32:35,240
blended. That's purple, but what's that color next to it?

438
00:32:35,240 --> 00:32:39,240
Some people think that it's indigo, but it's really just deep blue. Scientists using advanced

439
00:32:39,240 --> 00:32:43,240
instruments have discovered that indigo is not really a color of the spectrum. Wait a minute,

440
00:32:43,240 --> 00:32:47,240
so now it's royalty blue? I'm afraid so, but I can still help you remember

441
00:32:47,240 --> 00:32:51,240
the colors in their order. I'm confused. Purple,

442
00:32:51,240 --> 00:32:55,240
it doesn't start with a V, so is it still purple? Well, it's actually for violet,

443
00:32:55,240 --> 00:32:59,240
which is another name for purple. There's another way to make a spectrum.

444
00:32:59,240 --> 00:33:03,240
This is called a diffraction grating. Grating?

445
00:33:03,240 --> 00:33:07,240
Is that like grating cheese? Because that hurts my knuckles.

446
00:33:07,240 --> 00:33:11,240
Oh, nothing like that. Here, put on these glasses with diffraction grating.

447
00:33:11,240 --> 00:33:15,240
Look at that bright light source. Honey, what you see? Wow.

448
00:33:15,240 --> 00:33:19,240
It's the same rainbow color as we saw before,

449
00:33:19,240 --> 00:33:23,240
but the rainbows are everywhere. Let's try something a little different. This is called

450
00:33:23,240 --> 00:33:27,240
a spectrum tube, and it's filled with helium gas. What do you see?

451
00:33:27,240 --> 00:33:31,240
It's really different. All the colors aren't there, only some of them.

452
00:33:31,240 --> 00:33:35,240
Well, the diffraction grating separates the colors just like the prism does, but the

453
00:33:35,240 --> 00:33:39,240
gases in the tube don't produce the complete rainbow of colors. What property

454
00:33:39,240 --> 00:33:43,240
of light allows the diffraction gratings in the prisms to separate the colors?

455
00:33:43,240 --> 00:33:47,240
I don't know. I think it's wavelengths. Mr. Turner at NASA

456
00:33:47,240 --> 00:33:51,240
told us that different colors, like blue and red, have different wavelengths.

457
00:33:51,240 --> 00:33:55,240
That's right. They are two of the colors of the visible spectrum. You might want

458
00:33:55,240 --> 00:33:59,240
to learn more about the visible spectrum. I know a NASA Langley researcher, Doreen Neal.

459
00:33:59,240 --> 00:34:03,240
She's going to be over at the Virginia Children's Museum. That sounds like our next stop.

460
00:34:07,240 --> 00:34:11,240
Look, she's blowing bubbles. That's so neat.

461
00:34:11,240 --> 00:34:15,240
Are you Mrs. Neal? Yes, I am, and you must be the treehouse detectives.

462
00:34:15,240 --> 00:34:19,240
Yes, we are. Wow, look at those bubbles. It looks like a rainbow.

463
00:34:19,240 --> 00:34:23,240
You were just talking about the colors of a rainbow. How can I help you?

464
00:34:23,240 --> 00:34:27,240
We need to know more about the visible spectrum. Tell me what you've learned so far.

465
00:34:27,240 --> 00:34:31,240
Waves have different frequencies. And different frequencies mean

466
00:34:31,240 --> 00:34:35,240
different colors. The order of the waves and the frequencies is called the

467
00:34:35,240 --> 00:34:39,240
electromagnetic spectrum. The part that our eyes can see is only a very

468
00:34:39,240 --> 00:34:43,240
small part of the electromagnetic spectrum, and that's the part we call

469
00:34:43,240 --> 00:34:47,240
visible spectrum. That makes sense. Would the other parts of the spectrum do

470
00:34:47,240 --> 00:34:51,240
anything? Oh, yes. Televisions and radios and

471
00:34:51,240 --> 00:34:55,240
microwaves and cell phones all work on the electromagnetic

472
00:34:55,240 --> 00:34:59,240
spectrum. So tell us more about the visible spectrum.

473
00:34:59,240 --> 00:35:03,240
The visible spectrum consists of all the colors our eyes can see.

474
00:35:03,240 --> 00:35:07,240
Like orange, red, and yellow. And green, blue, and violet.

475
00:35:07,240 --> 00:35:11,240
That's right. Take a look at this color wheel. We can mix

476
00:35:11,240 --> 00:35:15,240
those colors to make all the colors our eyes can see. If we mix all

477
00:35:15,240 --> 00:35:19,240
the colors with white, we get white light. How can we see the colors in white light?

478
00:35:19,240 --> 00:35:23,240
We use a spectrometer to pick out the different frequencies.

479
00:35:23,240 --> 00:35:27,240
Mr. Turner showed us one of those. Let me show you something.

480
00:35:27,240 --> 00:35:31,240
When you mix the three primary colors of pigment,

481
00:35:31,240 --> 00:35:35,240
you get black, because pigment

482
00:35:35,240 --> 00:35:39,240
absorbs all the light that hits it. That's what pigment is. But with light,

483
00:35:39,240 --> 00:35:43,240
is it different? Yes, it is. The primary colors of light are red,

484
00:35:43,240 --> 00:35:47,240
green, and blue. And when you mix those three, you get white

485
00:35:47,240 --> 00:35:51,240
light. I hope you learned a lot about the electromagnetic spectrum today.

486
00:35:51,240 --> 00:35:55,240
The museum has a room full of light and color that tracks your motions.

487
00:35:55,240 --> 00:35:59,240
I think you might want to check it out. Let's go. Thanks, Ms. Neal.

488
00:35:59,240 --> 00:36:03,240
Bye.

489
00:36:03,240 --> 00:36:07,240
What are you doing? I'm doing an experiment with colored lights.

490
00:36:07,240 --> 00:36:11,240
I wrapped each light with colored paper and foil. Okay.

491
00:36:11,240 --> 00:36:15,240
There's red, green, and blue. Why do you use the foil?

492
00:36:15,240 --> 00:36:19,240
The foil makes the light shine in one direction. What do you think would happen if I placed all the colors

493
00:36:19,240 --> 00:36:23,240
of light together? I guess you'd have a bunch of mixed up colors.

494
00:36:23,240 --> 00:36:27,240
Watch. Here. Hold that, and you hold that. Now we're going to shine this light on this board.

495
00:36:27,240 --> 00:36:31,240
Watch what happens. It makes a white light.

496
00:36:31,240 --> 00:36:35,240
That's right. White light does make all the colors of the rainbow.

497
00:36:35,240 --> 00:36:39,240
I'm Ted Toon with this KSNN special report.

498
00:36:39,240 --> 00:36:43,240
Mount Luminous, the active volcano on the western Pacific island of

499
00:36:43,240 --> 00:36:47,240
Iguapucu, has erupted yet again just this morning.

500
00:36:47,240 --> 00:36:51,240
We flew our reporter, I Am Listening, to the scene, and she brings us this live report.

501
00:36:51,240 --> 00:36:55,240
I Am? Thanks, Ted.

502
00:36:55,240 --> 00:36:59,240
Mount Luminous is really blowing its top. I Am!

503
00:36:59,240 --> 00:37:03,240
Can you tell if there are rivers of gushing red-hot lava or giant

504
00:37:03,240 --> 00:37:07,240
flaming boulders crashing down from out of the sky?

505
00:37:07,240 --> 00:37:11,240
I can't see a darn thing. We're out of here.

506
00:37:11,240 --> 00:37:15,240
Well, there you have it.

507
00:37:15,240 --> 00:37:19,240
I'm Ted Toon saying that's all there is for today. Join us tomorrow

508
00:37:19,240 --> 00:37:23,240
when we'll be sending I Am Listening out to find a really good volcano with

509
00:37:23,240 --> 00:37:27,240
lava and flaming boulders and stuff.

510
00:37:27,240 --> 00:37:31,240
I got it! Volcanoes erupt lava. What are you talking about?

511
00:37:31,240 --> 00:37:35,240
KSNN is on the scene of an active volcano. Lava's red.

512
00:37:35,240 --> 00:37:39,240
So maybe the red lava's reflecting into the sky. Oh yeah, we learned about reflection

513
00:37:39,240 --> 00:37:43,240
from the Jefferson Lab. Maybe we have a new hypothesis. If a volcano

514
00:37:43,240 --> 00:37:47,240
erupts red lava, then the sky may be red due to reflection. I think

515
00:37:47,240 --> 00:37:51,240
we need to learn more about volcanoes. I have to go study for a test. See you later.

516
00:37:51,240 --> 00:37:55,240
Alright, bye, BJ. Good luck, man. Alright, thanks. I have this book about volcanoes.

517
00:37:55,240 --> 00:37:59,240
Let's look up Mount Luminous.

518
00:37:59,240 --> 00:38:03,240
Here's Mount Luminous. It says

519
00:38:03,240 --> 00:38:07,240
it's located in the Pacific Ocean, near Japan. That book says something about

520
00:38:07,240 --> 00:38:11,240
it being in the Ring of Fire. I have that book.

521
00:38:11,240 --> 00:38:15,240
The Ring of Fire? If there's a ring of fire in the ocean, that could be why the sky is red.

522
00:38:15,240 --> 00:38:19,240
Let's look at the globe. Here we are

523
00:38:19,240 --> 00:38:23,240
and here's the Pacific Ocean. How far is it from us? Well, my

524
00:38:23,240 --> 00:38:27,240
spatial studies teacher said that all globes have a scale. Here it is.

525
00:38:27,240 --> 00:38:31,240
It says one centimeter is equal to 418 kilometers.

526
00:38:31,240 --> 00:38:35,240
So we need to measure how far Virginia is from Mount Luminous. Okay.

527
00:38:35,240 --> 00:38:39,240
Let's see. That would be

528
00:38:39,240 --> 00:38:43,240
27 centimeters. I'll do the math.

529
00:38:43,240 --> 00:38:47,240
One centimeter equals 418

530
00:38:47,240 --> 00:38:51,240
kilometers.

531
00:38:51,240 --> 00:38:55,240
Multiply that by 27 centimeters.

532
00:39:05,240 --> 00:39:09,240
That's about

533
00:39:09,240 --> 00:39:13,240
11,286 kilometers.

534
00:39:13,240 --> 00:39:17,240
And there's about 1.6 kilometers in a mile, so that's about 7,000 miles.

535
00:39:17,240 --> 00:39:21,240
But I don't think a reflection of red lava could be seen 7,000 miles away.

536
00:39:21,240 --> 00:39:25,240
As scientists, we need to do a little more research and experimentation

537
00:39:25,240 --> 00:39:29,240
before we jump to any conclusions. Dr. Politsky said that volcanoes can put out

538
00:39:29,240 --> 00:39:33,240
a lot of pollution in the air. Maybe pollution is causing the sunrises and sunsets to be

539
00:39:33,240 --> 00:39:37,240
so red. I don't think so. 7,000 miles is a long way to

540
00:39:37,240 --> 00:39:41,240
travel, even for pollution. But you never know. Different types of volcanoes

541
00:39:41,240 --> 00:39:45,240
could cause different types of pollution. So what do we do next?

542
00:39:45,240 --> 00:39:49,240
I think we should see if anyone in the NASA Wildfiles Kids Club has done any research on volcanoes.

543
00:39:49,240 --> 00:39:53,240
Hi, Kaylee. Hi, Kaylee. Hi, Kaylee.

544
00:39:53,240 --> 00:39:57,240
I knew I could help you guys out. I'll send the question to all our club members.

545
00:39:57,240 --> 00:40:01,240
Good, because I have to run. Bye. I wonder what makes volcanoes erupt.

546
00:40:01,240 --> 00:40:05,240
Is it like an earthquake? I don't know, but I don't want to be around for either.

547
00:40:05,240 --> 00:40:09,240
Hey, look, I'm getting a response from Mr. Thomas' class

548
00:40:09,240 --> 00:40:13,240
at Burbank Elementary in Hampton, Virginia. They've been studying volcanoes

549
00:40:13,240 --> 00:40:17,240
and have even made some models. Let's dial them up to see if we can do a teleconference

550
00:40:17,240 --> 00:40:21,240
to find out how much they know about volcanoes.

551
00:40:21,240 --> 00:40:25,240
Hi, my name is Robert Bryan,

552
00:40:25,240 --> 00:40:29,240
a fifth grade student in Mr. Thomas' class. What is your project?

553
00:40:29,240 --> 00:40:33,240
Well, we have been studying volcanoes, and we have found out that there are three basic types of volcanoes.

554
00:40:33,240 --> 00:40:37,240
What are they? Let me show you some of the models that we've made then.

555
00:40:37,240 --> 00:40:41,240
This one is a model of a composite volcano.

556
00:40:41,240 --> 00:40:45,240
Its eruptions vary between quiet and violent ones.

557
00:40:45,240 --> 00:40:49,240
When the volcano has a violent one, it throws out ash and dust, creating a temperate layer.

558
00:40:49,240 --> 00:40:53,240
Wow, that's cool. What are the quiet eruptions like?

559
00:40:53,240 --> 00:40:57,240
That is when the volcano erupts lava, like this.

560
00:40:57,240 --> 00:41:01,240
What are the other two types?

561
00:41:01,240 --> 00:41:05,240
Another volcano is a cinder cone volcano.

562
00:41:05,240 --> 00:41:09,240
This volcano only erupts ash and dust, like this.

563
00:41:09,240 --> 00:41:13,240
And there is a shield volcano.

564
00:41:13,240 --> 00:41:17,240
Shield? You mean like what knights used to defend themselves?

565
00:41:17,240 --> 00:41:21,240
Well, sort of. Take a look at our model.

566
00:41:21,240 --> 00:41:25,240
As you can see, the lava flows differently.

567
00:41:25,240 --> 00:41:29,240
That's interesting. We learned a lot. Thanks for your help.

568
00:41:29,240 --> 00:41:33,240
Bye from the NASA Wildfiles Kids Club in Manhattan, Virginia.

569
00:41:33,240 --> 00:41:37,240
See you later.

570
00:41:37,240 --> 00:41:41,240
We should build a volcano. That looks like fun.

571
00:41:41,240 --> 00:41:45,240
Let's do a little research. Let's see what Dr. Textbook has to say about volcanoes.

572
00:41:45,240 --> 00:41:49,240
And now, the History of Volcanoes with Dr. Textbook.

573
00:41:49,240 --> 00:41:53,240
Hello. Did you know that the word

574
00:41:53,240 --> 00:41:57,240
volcano comes from the Roman god of fire Vulcan,

575
00:41:57,240 --> 00:42:01,240
and that the early Hawaiians told legends of their goddess

576
00:42:01,240 --> 00:42:05,240
of fire, Pele. In the year 79 AD,

577
00:42:05,240 --> 00:42:09,240
the Romans were the first ones to write an eyewitness account of an actual

578
00:42:09,240 --> 00:42:13,240
volcanic eruption. Falling ash spewed out of Mount Vesuvius,

579
00:42:13,240 --> 00:42:17,240
and the ash and the mud flows combined to bury the nearby city of

580
00:42:17,240 --> 00:42:21,240
Pompeii, thus killing about 2,000 people. 2,000 years later,

581
00:42:21,240 --> 00:42:25,240
archaeologists actually unearthed this ancient city of Pompeii.

582
00:42:25,240 --> 00:42:29,240
In April 1902, Mount Pele, not related to the Hawaiian

583
00:42:29,240 --> 00:42:33,240
goddess of fire, in the Caribbean Sea exploded, killing 28,000

584
00:42:33,240 --> 00:42:37,240
residents in just seconds in the little town of St. Pierre.

585
00:42:37,240 --> 00:42:41,240
Closer to home, in 1980, the sleeping giant

586
00:42:41,240 --> 00:42:45,240
Mount St. Helens erupted to become the most destructive volcano

587
00:42:45,240 --> 00:42:49,240
in U.S. history. The eruption had the force of

588
00:42:49,240 --> 00:42:53,240
10 million tons of dynamite, and shook the Cascade Mountain Range in Oregon

589
00:42:53,240 --> 00:42:57,240
and the state of Washington. So, in honor of all

590
00:42:57,240 --> 00:43:01,240
the gods of fire, I will attempt to find out what really makes a volcano

591
00:43:01,240 --> 00:43:05,240
come alive!

592
00:43:09,240 --> 00:43:13,240
Not a very good idea.

593
00:43:13,240 --> 00:43:17,240
See, Dr. Textbook? He's so funny.

594
00:43:17,240 --> 00:43:21,240
Let's research Mount Luminous. I saw an article about Mount Luminous

595
00:43:21,240 --> 00:43:25,240
in the paper today. Maybe it'll have some information for us. It said that Mount Luminous

596
00:43:25,240 --> 00:43:29,240
was a cinder cone, and that its first eruption was a month ago.

597
00:43:29,240 --> 00:43:33,240
Then Mount Luminous can't be the problem, because why would all of a sudden the skies be a deep red

598
00:43:33,240 --> 00:43:37,240
if it erupted a month ago? I don't know, but I think we need to know more about

599
00:43:37,240 --> 00:43:41,240
volcanoes. Solving problems is hard work. My mom has

600
00:43:41,240 --> 00:43:45,240
to go to California on business to the NASA Dragon Research Center and the Jet Propulsion

601
00:43:45,240 --> 00:43:49,240
Laboratory. Maybe we should go with her. Okay, let's see if we can go.

602
00:43:49,240 --> 00:43:53,240
Hi, you must be the Treehouse Detectives. And you are

603
00:43:53,240 --> 00:43:57,240
Dr. Pieri? I'm afraid so. What's that plane behind you?

604
00:43:57,240 --> 00:44:01,240
I've never seen anything like that before. Well, it's an ER-2. It's a

605
00:44:01,240 --> 00:44:05,240
NASA research aircraft used at high altitude. What kind of research does NASA

606
00:44:05,240 --> 00:44:09,240
do with this plane? Well, this plane has high-powered cameras, and they can see

607
00:44:09,240 --> 00:44:13,240
a wide variety of phenomena, including hurricanes, volcanoes,

608
00:44:13,240 --> 00:44:17,240
earthquakes, and it can also monitor ozone. Do you mean you actually

609
00:44:17,240 --> 00:44:21,240
fly into a volcano when it's erupting? Oh no, it would do a lot

610
00:44:21,240 --> 00:44:25,240
of damage to an airplane like this. But how can this cause damage?

611
00:44:25,240 --> 00:44:29,240
Well, this isn't so much the problem. This lava rock gets ground up into

612
00:44:29,240 --> 00:44:33,240
fine particulate material like this. This is volcanic ash. This is the problem.

613
00:44:33,240 --> 00:44:37,240
That's really light. Where are most of the volcanoes located?

614
00:44:37,240 --> 00:44:41,240
There are active volcanoes in every ocean basin on almost every continent in the world.

615
00:44:41,240 --> 00:44:45,240
Most volcanoes are underwater and form along ridges as ocean basins spread

616
00:44:45,240 --> 00:44:49,240
away from them. Sometimes volcanoes form in the middle of continents and ocean

617
00:44:49,240 --> 00:44:53,240
basins as hot spots heat up plates. Plates?

618
00:44:53,240 --> 00:44:57,240
The Earth's crust is actually broken into pieces that we call plates. In fact, another

619
00:44:57,240 --> 00:45:01,240
place where volcanoes form is where one plate goes underneath another plate. And that happens

620
00:45:01,240 --> 00:45:05,240
in the Pacific Ocean. Are you talking about the Ring of Fire? The Ring of Fire

621
00:45:05,240 --> 00:45:09,240
is a ring of volcanoes that surround the Pacific Ocean where the continents meet the

622
00:45:09,240 --> 00:45:13,240
ocean basin. We learned that Mount Luminous is a cinder cone. Could you tell us

623
00:45:13,240 --> 00:45:17,240
more about cinder cones? Well, sure. For instance, when cinder cones form

624
00:45:17,240 --> 00:45:21,240
the magma is so sticky that the gas stays trapped inside it until the pressure

625
00:45:21,240 --> 00:45:25,240
builds so much that it just literally explodes. And when it explodes

626
00:45:25,240 --> 00:45:29,240
it forms lots of pyroclastic material which is really sharp.

627
00:45:29,240 --> 00:45:33,240
Maybe we're getting a little closer. Thanks, Dr. Peary.

628
00:45:33,240 --> 00:45:37,240
We learned so much about volcanoes. Well, I hope this information gives you

629
00:45:37,240 --> 00:45:41,240
your answer. Thank you so much. Good luck. Bye. Bye-bye.

630
00:45:41,240 --> 00:45:45,240
We know Mount Luminous is a cinder cone

631
00:45:45,240 --> 00:45:49,240
and that means it doesn't even have lava. That means our hypothesis is wrong.

632
00:45:49,240 --> 00:45:53,240
But I don't think we have enough information yet to change our hypothesis.

633
00:45:53,240 --> 00:45:57,240
Let's go do some more research and experimentation. Let's get back to the treehouse.

634
00:45:57,240 --> 00:46:01,240
What's up? Could the volcano be causing the red sky?

635
00:46:01,240 --> 00:46:05,240
Could it be that all colors other than red are being absorbed by something?

636
00:46:05,240 --> 00:46:09,240
You missed the exciting conclusion of The Case of the Mysterious Red Light.

637
00:46:17,240 --> 00:46:21,240
You're very close now. Answer these questions

638
00:46:21,240 --> 00:46:25,240
and you will solve the treehouse detective's latest mystery.

639
00:46:25,240 --> 00:46:29,240
What do researchers do at the NASA cave?

640
00:46:29,240 --> 00:46:33,240
What are two things that affect how far wind

641
00:46:33,240 --> 00:46:37,240
and water carry particles? How does the jet stream

642
00:46:37,240 --> 00:46:41,240
help the treehouse detectives solve their problem?

643
00:46:41,240 --> 00:46:45,240
What are you doing? Magic?

644
00:46:45,240 --> 00:46:49,240
No, this is actually a science experiment. I punched a hole in this cup and poured water in.

645
00:46:49,240 --> 00:46:53,240
What happens? Turn the lights down and watch this.

646
00:46:53,240 --> 00:46:57,240
Wow, that looks like a stream of light.

647
00:46:57,240 --> 00:47:01,240
The light is bending, just like the experiment Dr. Shin told us at the Jefferson Lab.

648
00:47:01,240 --> 00:47:05,240
It's neat, but we still need to figure out why the sunrises and sunsets are so red.

649
00:47:05,240 --> 00:47:09,240
I think pollution could be the cause.

650
00:47:09,240 --> 00:47:13,240
But what's making the pollution? I don't think it's the volcanoes, because they're too far away.

651
00:47:13,240 --> 00:47:17,240
Maybe the wind's blowing it our way. Yeah, right. I don't think the wind can blow things this far.

652
00:47:17,240 --> 00:47:21,240
Not unless it had a lot of hot air, unlike someone we know.

653
00:47:21,240 --> 00:47:25,240
I know you're not talking about me. I'll go over to the problem board and try to figure out what we need to do next.

654
00:47:25,240 --> 00:47:29,240
We know the sky is still red.

655
00:47:29,240 --> 00:47:33,240
We know that there are waves and that it's also a ray, and the light we see is only a small part of the spectrum.

656
00:47:33,240 --> 00:47:37,240
And we also know that light reflects and refracts.

657
00:47:37,240 --> 00:47:41,240
Pollution can cause red skies.

658
00:47:41,240 --> 00:47:45,240
Volcanoes cause some air pollution when they erupt dust and ash.

659
00:47:45,240 --> 00:47:49,240
We need to know how far ash can travel through the air and if it can travel long distances.

660
00:47:49,240 --> 00:47:53,240
But how do we find out? We need someone who knows a lot about wind.

661
00:47:53,240 --> 00:47:57,240
Wind has to do with weather. I'm sure NASA has a weather expert.

662
00:47:57,240 --> 00:48:01,240
Wow, look. NASA has a really cool place called the cave.

663
00:48:01,240 --> 00:48:05,240
It's a computer system that we can use to look at weather in 3D.

664
00:48:05,240 --> 00:48:09,240
I'll go over there.

665
00:48:09,240 --> 00:48:13,240
This must be the cave. Hi, I'm Dr. Jennifer Olsen.

666
00:48:13,240 --> 00:48:17,240
I'm one of the treehouse detectives. We're trying to learn more about wind.

667
00:48:17,240 --> 00:48:21,240
We want to know if volcanic ash can blow all the way from the Pacific Ocean to Virginia.

668
00:48:21,240 --> 00:48:25,240
I'm looking at some data in the cave right now. Would you like to step in with me and take a look?

669
00:48:25,240 --> 00:48:29,240
I've heard of the cave. Sure, let's go.

670
00:48:29,240 --> 00:48:33,240
First, you'll need to take off your shoes and put on the glasses.

671
00:48:33,240 --> 00:48:37,240
Wow, this is neat.

672
00:48:37,240 --> 00:48:41,240
We're looking at wind vectors over the Pacific Ocean and the U.S.

673
00:48:41,240 --> 00:48:45,240
What's a wind vector? Do you see the yellow arrows?

674
00:48:45,240 --> 00:48:49,240
Yeah, lots of them. Those are wind vectors. They show which direction the wind is blowing.

675
00:48:49,240 --> 00:48:53,240
Their size tells you how fast the wind is blowing.

676
00:48:53,240 --> 00:48:57,240
What about the wind vectors way up there?

677
00:48:57,240 --> 00:49:01,240
These vectors are up at 12 miles over the Earth's surface.

678
00:49:01,240 --> 00:49:05,240
That's well above the weather.

679
00:49:05,240 --> 00:49:09,240
It looks like all those arrows are pointing in the same direction. Is that normal for high altitudes?

680
00:49:09,240 --> 00:49:13,240
Yes, it is. Notice that these arrows are mostly pointing from the west toward the east.

681
00:49:13,240 --> 00:49:17,240
That's a zonal direction in the global wind pattern.

682
00:49:17,240 --> 00:49:21,240
How fast are they blowing?

683
00:49:21,240 --> 00:49:25,240
They're blowing between 40 and 50 miles per hour.

684
00:49:25,240 --> 00:49:29,240
At these altitudes, there's also something that we call a jet stream.

685
00:49:29,240 --> 00:49:33,240
Oh, you mean the white stuff that comes out the back of a jet we see.

686
00:49:33,240 --> 00:49:37,240
Good guess, but the jet stream is a river of very fast-flowing air

687
00:49:37,240 --> 00:49:41,240
where speeds can reach several hundred miles per hour.

688
00:49:41,240 --> 00:49:45,240
That's as fast as a major tornado. Let's step outside and go to my computer lab.

689
00:49:45,240 --> 00:49:49,240
Okay. So what's the second thing that affects how far wind can transport particles?

690
00:49:49,240 --> 00:49:53,240
Particles have a tremendous amount of data available to them to study things like lifetimes of gases and particles,

691
00:49:53,240 --> 00:49:57,240
and much of that data is stored here at the Atmospheric Science Data Center.

692
00:49:57,240 --> 00:50:01,240
I didn't know particles had a life.

693
00:50:01,240 --> 00:50:05,240
Yes. Lifetime refers to how long the particle stays in the atmosphere.

694
00:50:05,240 --> 00:50:09,240
For a particle near the surface, ash and dust will be rained out of the atmosphere within a matter of days.

695
00:50:09,240 --> 00:50:13,240
So volcanic ash would not have a very long lifetime.

696
00:50:13,240 --> 00:50:17,240
Not necessarily. If the ash were injected up in the atmosphere, near the stratosphere,

697
00:50:17,240 --> 00:50:21,240
its lifetime could be very long, in the order of weeks or months.

698
00:50:21,240 --> 00:50:25,240
Would zonal winds then be able to carry the ash to Virginia?

699
00:50:25,240 --> 00:50:29,240
Yes, it could. If a volcano injected particles into the stratosphere,

700
00:50:29,240 --> 00:50:33,240
it could be transported for very long distances by the very fast wind speeds of the jet stream.

701
00:50:33,240 --> 00:50:37,240
Yeah, but the Pacific Ocean is so far away. That would take forever.

702
00:50:37,240 --> 00:50:41,240
Let's do a quick calculation. It's about 7,000 miles from here to Mount Luminous.

703
00:50:41,240 --> 00:50:45,240
If we take a typical atmospheric wind speed of about 40 miles per hour,

704
00:50:45,240 --> 00:50:49,240
what do you get?

705
00:50:49,240 --> 00:50:53,240
175 hours.

706
00:50:53,240 --> 00:50:57,240
175 hours to transport the dust to Virginia. That's about a week.

707
00:50:57,240 --> 00:51:01,240
In fact, the dust plume could be transported completely around the globe in about a month.

708
00:51:01,240 --> 00:51:05,240
The sky is so deep red. Is there anything about this eruption that is different?

709
00:51:05,240 --> 00:51:09,240
Yes, there is. I read that this volcano also injected a lot of

710
00:51:09,240 --> 00:51:13,240
sulfur dioxide and water vapor into the stratosphere.

711
00:51:13,240 --> 00:51:17,240
The particles react together to form tiny sulfuric acid particles.

712
00:51:17,240 --> 00:51:21,240
We learned from Dr. Poluski that particles scatter the blue light.

713
00:51:21,240 --> 00:51:25,240
That's right. And these particles are small enough that they act with the molecules in the atmosphere

714
00:51:25,240 --> 00:51:29,240
to scatter even more of the blue light from the sun's rays.

715
00:51:29,240 --> 00:51:33,240
Thanks, Dr. Olson. Sure. I think we now have a new hypothesis.

716
00:51:33,240 --> 00:51:37,240
Here it is. If the zonal winds brought the volcanic ash to this area,

717
00:51:37,240 --> 00:51:41,240
we would have deep red sunsets and sunrises. Smart thinking, huh?

718
00:51:43,240 --> 00:51:47,240
Matt said the cave was really cool. I wish you could have one here in the treehouse.

719
00:51:47,240 --> 00:51:51,240
I think that would be a little too high tech, even for our treehouse.

720
00:51:51,240 --> 00:51:55,240
You know what, guys? I've been thinking. Our hypothesis is incorrect.

721
00:51:55,240 --> 00:51:59,240
Why? Well, you remember when Dr. Olson

722
00:51:59,240 --> 00:52:03,240
told us that the zonal winds would bring the ash and dust to our area in about seven days?

723
00:52:03,240 --> 00:52:07,240
Yeah. Well, the really red sunsets and sunrises came

724
00:52:07,240 --> 00:52:11,240
only three days after Mount Luminous erupted.

725
00:52:11,240 --> 00:52:15,240
That's why it's called a volcano, because it happened too soon.

726
00:52:15,240 --> 00:52:19,240
But guys, you're forgetting. Dr. Olson also told us about jet streams and how they travel really fast.

727
00:52:19,240 --> 00:52:23,240
Couldn't the ash and dust have gotten here by the jet stream?

728
00:52:23,240 --> 00:52:27,240
I think we need to find out more about jet streams.

729
00:52:27,240 --> 00:52:31,240
Here comes Bianca. Are you guys talking about jet streams?

730
00:52:31,240 --> 00:52:35,240
Yes. The weatherman from Wavy TV Tank came to our school last week.

731
00:52:35,240 --> 00:52:39,240
He said if we had any questions, to contact him. I'll email him and see if we can meet him.

732
00:52:39,240 --> 00:52:43,240
Yes, Mr. Eco. We need to learn more about a jet stream.

733
00:52:43,240 --> 00:52:47,240
Sure. I can show you a jet stream. You have one here?

734
00:52:47,240 --> 00:52:51,240
Only on a screen. What do you guys know about jet streams?

735
00:52:51,240 --> 00:52:55,240
We know that a jet stream is like a river of wind, way up high in the atmosphere.

736
00:52:55,240 --> 00:52:59,240
And that they can travel up to a few hundred miles per hour. That's great.

737
00:52:59,240 --> 00:53:03,240
Is the jet stream always in the same place? No. Let me show you.

738
00:53:03,240 --> 00:53:07,240
Actually, guys, there are multiple jet streams. Let's take a look at a couple of them.

739
00:53:07,240 --> 00:53:11,240
We have the Southern Jet, and that is outlined in the blue.

740
00:53:11,240 --> 00:53:15,240
That's responsible for a lot of the cold air that comes down to the East Coast.

741
00:53:15,240 --> 00:53:19,240
And then we have what we call the Subtropical Jet. That is outlined in the red right here.

742
00:53:19,240 --> 00:53:23,240
And that's responsible for bringing in a lot of warm, moist air for the East Coast.

743
00:53:23,240 --> 00:53:27,240
We need to know if the jet stream was passing over our area the week that Mount Lemona surrupted.

744
00:53:27,240 --> 00:53:31,240
Sure. Let's go look at the data.

745
00:53:31,240 --> 00:53:35,240
Actually, look. Over the past five to seven days,

746
00:53:35,240 --> 00:53:39,240
the jet stream goes further and further south. And what that does is it brings in all types of systems.

747
00:53:39,240 --> 00:53:43,240
And it's basically just below us, which lets everything drain down into our region.

748
00:53:43,240 --> 00:53:47,240
So you can see as the jet stream goes further south,

749
00:53:47,240 --> 00:53:51,240
all of the clouds and all the debris comes right down on top of us.

750
00:53:51,240 --> 00:53:55,240
That has to be it, then. If the jet stream traveled at 100 miles per hour,

751
00:53:55,240 --> 00:53:59,240
and Mount Luminous is 7,000 miles away, then it would take 70 hours for the ash to reach our area.

752
00:53:59,240 --> 00:54:03,240
With 24 hours in a day, three days would be 72 hours.

753
00:54:03,240 --> 00:54:07,240
What does that mean so the jet stream could cause the sunrises and sunsets to be red?

754
00:54:07,240 --> 00:54:09,240
I think you guys have solved the mystery.

755
00:54:09,240 --> 00:54:11,240
Thanks, Mr. Ika. We really appreciate your help.

756
00:54:11,240 --> 00:54:15,240
Any time for the treehouse detectives.

757
00:54:17,240 --> 00:54:19,240
I'm so glad that we finally solved our mystery.

758
00:54:19,240 --> 00:54:21,240
But I still think there's one last thing we need to do.

759
00:54:21,240 --> 00:54:25,240
Let's email our kids club members and ask them if they've been seeing redder sunrises and sunsets.

760
00:54:25,240 --> 00:54:29,240
That's a good idea. That way we'll know it's not just happening in our area.

761
00:54:29,240 --> 00:54:31,240
Great. Also ask them when they first notice the change.

762
00:54:31,240 --> 00:54:33,240
Okay.

763
00:54:38,240 --> 00:54:41,240
We're getting a lot of emails from all over the U.S.

764
00:54:41,240 --> 00:54:45,240
A lot of our kids club members are saying that they are seeing redder sunrises and sunsets.

765
00:54:45,240 --> 00:54:49,240
Let's organize the emails by states and see when everyone first saw the unusual skies.

766
00:54:49,240 --> 00:54:52,240
Wow, there's a pattern with the states of the West Coast.

767
00:54:52,240 --> 00:54:56,240
This email says they saw redder skies only two days after Mount Luminous erupted.

768
00:54:56,240 --> 00:55:00,240
The center of the U.S. saw the unusual skies about three days after the eruption.

769
00:55:00,240 --> 00:55:02,240
Except for the school in Dallas.

770
00:55:02,240 --> 00:55:05,240
Their email says they saw the redder skies just two days after the eruption.

771
00:55:05,240 --> 00:55:06,240
That's strange.

772
00:55:06,240 --> 00:55:10,240
Well, remember, the jet stream did travel down into their area before it came up to us in Virginia.

773
00:55:10,240 --> 00:55:15,240
You're right. I think if these emails remove all doubt that it was the eruption of Mount Luminous

774
00:55:15,240 --> 00:55:18,240
that caused the unusual red sunrises and sunsets.

775
00:55:18,240 --> 00:55:20,240
Hi, Dr. D.

776
00:55:20,240 --> 00:55:23,240
Hi. Did you find a solution to your red sky problem yet?

777
00:55:23,240 --> 00:55:24,240
We're pretty sure that we have.

778
00:55:24,240 --> 00:55:27,240
And we did it together with the help of the scientific method.

779
00:55:27,240 --> 00:55:29,240
And we learned a lot about light along the way.

780
00:55:29,240 --> 00:55:31,240
We learned the way light travels.

781
00:55:31,240 --> 00:55:33,240
We learned a lot about frequency and wavelengths.

782
00:55:33,240 --> 00:55:37,240
Our first hypothesis was that there was a lot of low frequency waves in the sky.

783
00:55:37,240 --> 00:55:39,240
There was really nothing wrong with our statement.

784
00:55:39,240 --> 00:55:41,240
It just didn't explain why the sky was red.

785
00:55:41,240 --> 00:55:45,240
At first we thought that the explanation might be that light was bouncing around in the sky.

786
00:55:45,240 --> 00:55:47,240
But that was just a wild guess.

787
00:55:47,240 --> 00:55:50,240
You then told us about transparent, translucent, and opaque.

788
00:55:50,240 --> 00:55:52,240
We thought that clouds might be the solution.

789
00:55:52,240 --> 00:55:54,240
And then we thought about pollution.

790
00:55:54,240 --> 00:55:56,240
But what could be causing the pollution?

791
00:55:56,240 --> 00:55:58,240
Then we really got sidetracked.

792
00:55:58,240 --> 00:56:01,240
We heard a report about a volcano called Mount Luminous that was erupting.

793
00:56:01,240 --> 00:56:04,240
We decided that the red could somehow be connected to the red lava.

794
00:56:04,240 --> 00:56:09,240
But we weren't listening to the report very carefully because it clearly stated that there was dust everywhere.

795
00:56:09,240 --> 00:56:11,240
And then we missed the big clue.

796
00:56:11,240 --> 00:56:15,240
I mean, we thought that since the volcano was so far away that it had nothing to do with our problem.

797
00:56:15,240 --> 00:56:19,240
Even though our idea about volcanoes was way off, we decided to study them.

798
00:56:20,240 --> 00:56:25,240
Then we were taught about volcanic ash and how it could stay in the air for months at a time and travel thousands of miles.

799
00:56:25,240 --> 00:56:27,240
And we began to get back in the right direction.

800
00:56:27,240 --> 00:56:29,240
So we didn't give up.

801
00:56:29,240 --> 00:56:35,240
We went back to our hypothesis of pollution and tried to see if it was the volcano that was giving off pollution or aerosols.

802
00:56:35,240 --> 00:56:40,240
We investigated wind and wind patterns and found that aerosols can be transported long distances.

803
00:56:40,240 --> 00:56:45,240
We learned that the higher up in the atmosphere aerosols are, the longer they can stay up there.

804
00:56:45,240 --> 00:56:53,240
Most importantly, we learned from Dr. Olson that it was possible for the aerosols to be scattered from the volcano all the way to Virginia, about 7,000 miles away.

805
00:56:53,240 --> 00:56:58,240
And don't forget, the jet stream helped to draw the aerosols to us even quicker.

806
00:56:58,240 --> 00:57:05,240
And the fact that Mount Luminous gave off a sulfur dioxide gas also helped explain why the sunrises and sunsets were such a deep red.

807
00:57:05,240 --> 00:57:14,240
That's great. You kept on track, researched carefully, kept an open mind, revised your hypothesis, and finally came up with a possible explanation.

808
00:57:14,240 --> 00:57:19,240
It was fun and a lot of hard work. There just wasn't some magical solution, that's for sure.

809
00:57:19,240 --> 00:57:25,240
It was a lot of hard work, but I believe you finally have come up with the most likely solution to the Red Sky Problem. Congratulations!

810
00:57:25,240 --> 00:57:31,240
Thank you. And now, for my final magic act, I'm going to make us all disappear.

811
00:57:31,240 --> 00:57:34,240
Are you still at that? Give it up.

812
00:57:34,240 --> 00:57:38,240
Abracadabra! Send them back to their homes!

813
00:57:40,240 --> 00:57:43,240
Hey, I think I did it! This is great!

814
00:57:43,240 --> 00:57:45,240
Jacob, we're still here!

815
00:57:46,240 --> 00:57:50,240
You made us disappear, but we're still stuck in the treehouse.

816
00:57:50,240 --> 00:57:52,240
Try it again, please!

817
00:57:53,240 --> 00:57:54,240
Psst, come here.

818
00:57:55,240 --> 00:57:59,240
Is this magic or just an illusion? See you next time.

819
00:58:04,240 --> 00:58:05,240
Yes, look at that.

820
00:58:08,240 --> 00:58:11,240
I didn't mess it up earlier. I don't know why I'm not getting it now.

821
00:58:12,240 --> 00:58:14,240
Six. Oh, yeah!

822
00:58:14,240 --> 00:58:16,240
Alright, bye PJ. Good luck, man.

823
00:58:16,240 --> 00:58:17,240
Alright, thanks.

824
00:58:21,240 --> 00:58:22,240
Don't laugh at me.

825
00:58:22,240 --> 00:58:23,240
Couldn't you hold it?

826
00:58:23,240 --> 00:58:25,240
I was holding it the whole time I was talking.

827
00:58:26,240 --> 00:58:27,240
Alright, alright.

828
00:58:30,240 --> 00:58:32,240
Let's see what Dr. Technique's got.

829
00:58:32,240 --> 00:58:33,240
Dr. D.

830
00:58:33,240 --> 00:58:34,240
Dr. Dial.

831
00:58:37,240 --> 00:58:40,240
You took this picture for my dad, and he's like, what?

832
00:58:40,240 --> 00:58:42,240
Okay, Carolyn, get over here and get your picture taken.

833
00:58:45,240 --> 00:58:47,240
So you want me to be like, holding it on the plane?

834
00:58:47,240 --> 00:58:48,240
Alright, alright.

835
00:58:48,240 --> 00:58:53,240
The NASA Y-Files is made possible through the generous support of Bush Gardens, SeaWorld,

836
00:58:53,240 --> 00:58:58,240
and NASA Langley Research Center's Aerospace Vehicle Systems Technology Office.