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NASA CONNECT: Data Analysis and Measurement: Having a Solar Blast!



Melissa Joan Hart

Hi! I’m Melissa Joan Hart. You might know me as Sabrina, The Teen Age Witch!

… I just made up that stuff so Morgan would leave.

Oh, I get it. No I don’t!

Sabrina, I’m no expert on magic but it looks to me like you’re under a spell.


You’re a witch, remember?

OH MY GOSH! You’re right! Hey! I never have to go shopping, again!

Although I play a student with some extra "special" abilities, I’m here to tell you that in real life there are no shortcuts to your education.

How would you like a Porsche?

I don’t drive a stick.

You do now!

Learning math, science and technology will help you work towards your dream.

In this episode of NASA CONNECT, you’ll learn how awesome our Sun really is.

You’ll observe NASA engineers and researchers using math, science, and technology to explore the Sun/Earth Connection.

In your classroom you’ll do a cool hands on activity as you chart the Sun’s solar cycles.

And, using the instructional technology activity, you will explore the web to discover even more about the Sun/Earth Connection….

So stay tuned as hosts Jennifer Pulley and Dan Geroe take you on another exciting episode of NASA CONNECT!



Dan Geroe

Hi! Welcome to NASA CONNECT. The show that connects you to math, science, technology and NASA! I’m Dan Geroe!

Jennifer Pulley

And I’m Jennifer Pulley!

Welcome to the Maryland Science Museum here in Baltimore, Maryland. Home of the Hubble Space Telescope National Visitors Center! Today’s show is about…

Jennifer Pulley and Dan Geroe


Jennifer Pulley

Did you know that it would take one million Earths to fill up the sun?

And get this - more than 99 percent of all matter in our solar system is in the Sun!

Dan Geroe

It only takes about 8 minutes for light from the Sun to reach Earth. And, as big as the Sun is, it is considered to be only an average-sized star.

Jennifer Pulley

Here’s another interesting fact: In 1989, the sun actually knocked out power in Canada


You mean, the Sun stopped electricity on the Earth?!

Dan Geroe

That’s right! We’ll tell you later how it happened!

Jennifer Pulley

In the next half-hour we hope to give you a better appreciation for how the Sun works; how it affects us here on earth;…

Dan Geroe

… and how NASA researchers study the sun!

Jennifer Pulley

But, before we continue, here are a few things you and your teacher need to know.

First, teachers… make sure you have the lesson guide for today’s program. It can be downloaded from our NASA CONNECT web site. In it, you’ll find a great math-based, hands-on activity, and a description of our instructional technology components!

Dan Geroe

Kids! You’ll want to keep your eyes on Norbert, because, every time he appears with questions, like this, have your cue cards from the lesson guide and your brain ready to answer the questions he gives you.

Jennifer Pulley

Oh… and teachers…if you are watching a taped version of this program, every time you see Norbert with a remote, that's your cue to pause the videotape and discuss the cue card questions.

And now, back to… The Sun! Uh, Dan, a little more on my right, please!

The sun is OUR nearest star. It provides us with warmth and light. We all know that the sun is important to life on Earth but few of us have been given a good description of the sun and its composition.

Dan Geroe

Our sun is an average star, similar to millions of others in the Universe — but it’s a BIG energy machine!

If you could capture the energy the Sun produces in one second — that would supply the United States with enough energy for the next 13 billion years!


Where does the sun’s power come from?

Jennifer Pulley

Good question. The basic energy source for the sun comes from nuclear fusion. This is when mass particles combine and tons of energy are released.

The core, or the inner most part of the sun, is made of hydrogen. The sun is so dense and its size is so large that light released from the core takes about 100,000 years to make its way to the surface. If the sun were to stop producing energy today, it would take 100,000 years for significant effects to be felt at the Earth! Scientists think there is enough hydrogen on the sun to continue producing energy for another 7 billion years.

Dan Geroe

For many centuries, little was known about the sun.

However, in the early 1600’s, the Italian Scientist Galileo used a telescope to take a closer look at the Sun. He found dark spots that occasionally appeared and drifted across the sun. He also noticed that the dark spots on the sun’s surface were constantly changing. These are called sunspots!


What are sun spots?

Dan Geroe

Let’s find out! NASA Goddard’s Dr. Eric Christian has some answers for us at the Naval Observatory. It’s a Blast!

Dr. Eric Christian

Thanks Dan!

The Sun is a fascinating place and a brilliant object to observe.

We observe the Sun through telescopes like this one …

… here at the Naval Observatory in Washington DC.

But satellites help us, too.

To get a better understanding of the Sun, let’s look at its different parts.

The visible surface of the Sun -that which we can actually "see" with the human eye" -

is called the Photosphere. Temperatures here are around 6000 degrees Celsius.

The next two outer layers of the Sun’s atmosphere are called the chromosphere and the corona. The corona is actually hotter than the Photosphere at temperatures of one to two million degrees Celsius.

The Corona is visible to the naked eye during solar eclipses.

Remember the dark spots or sunspots that Galileo studied with his telescope?

Well, sunspots are dark cool areas of the Sun’s surface where charged particles are emitted. The sunspot only looks dark relative to the brightness of the rest of the sun but its still pretty hot — 4000 degrees Celsius hot!

The average sunspot is about the same diameter of the earth.

Sunspots generate some of the most violent storms in the solar system.

When a sunspot erupts, we call this a solar flare. Solar Flares are some of the biggest explosions in the Solar System.

When a solar flare occurs, gas heat of more than tens of thousands of degrees and energy surpassing billions of atomic bombs is hurled out from the Sun.

Another type of explosion is the CME, or, coronal mass ejection. These explosions can reach speeds of millions of kilometers per hour and can reach the Earth in just three days.

Both solar flares and CMEs can be very disruptive to human activity on earth and in space as these storms — we call them solar storms — travel to the Earth.

Jennifer Pulley

You know, Dan, just like meteorologists use satellites to predict weather here on earth, NASA uses satellites to predict solar storms.

Dan Geroe

Wait a minute. You’re saying that in the future we will be talking about "solar" storms just like we talk about storms here on the earth?

Jennifer Pulley

You got it.

Dan Geroe

Hmm. Predicting the storms of the future….


This just in America! Things are brewing up inside sunspots. There'll be a high energy burst of X-rays flowing from the Sun. For you people on the moon, spf 3000 will come in handy as the pulse should be hitting Moon-base Norbert right now!



Jennifer Pulley

Solar storms have caused disruptions in our communications and power supplies.

For instance, in 1989…

… a solar storm knocked out electric power in Quebec, Canada. Six million homes were without power for 9 hours as a result of magnetic solar storms.

Dan Geroe

Predicting solar storms has huge benefits to us here on earth. If power companies could receive earlier storm alerts, they could minimize damage and power outages.

Jennifer Pulley

So what NASA is doing to warn us about these solar storms?

Dan Geroe

And to learn more about the Sun Earth Connection and how it affects us, I’ll show you a really cool web site you can do at home or at school.

Jennifer Pulley

In the meantime, I’m going to head to NASA Goddard Space Flight Center in Greenbelt, Maryland to talk with astronomer Dr. Sten Odenwald. He runs 'Ask the Space Scientist' with NASA's IMAGE satellite program

Cue Card Questions

1. What are some forms of electromagnetic radiation?

2. How can satellites help researchers monitor the Sun?

3. Why is it important to track solar storms as they approach Earth?

Dr. Sten Odenwald

If we want to get a clearer view of what the Sun is doing, we need to get out from under the earth's atmosphere which distorts what we see.

We have to use satellites to gather the data we need to learn how the sun works.

The Sun radiates at all energy levels. Radiation is energy that travels and spreads out as it goes. There are different types of radiation, let me show you…

Visible light that comes from a lamp in your house,

or radio waves that come from a radio station are two types of radiation.

Other examples of radiation are microwaves - that cook popcorn in a few minutes,

Infrared light…which restaurants use to keep food warm,

Ultraviolet light…. which causes our skin to burn,

X-rays….which help doctors look at your bones,

and gamma rays….which are emitted from radioactive materials.

Let’s apply this information to the Sun.

As Eric stated earlier, the photosphere emits energy primarily in visible light, while the lower corona emits energy in extreme ultra violet light and the upper corona in X-rays. By zeroing in on one particular light energy, we can study the various parts of the sun and how they interact.

Jennifer Pulley

Okay Dr. Odenwald, how can satellites help us to monitor and observe the Sun?

Dr. Sten Odenwald

With satellite technology, we can look at the sun 24 hours a day!

We can put satellites outside of the Earth’s atmosphere to collect valuable data from the Sun and to act as early warning devices against solar storms.

Three important satellites that monitor the Sun and provide us with real-time data are the SOHO, ACE, and IMAGE satellites.

If you’d like to learn more about the SOHO satellite, Dr. Terry Kucera, a researcher here at NASA Goddard, has all the info.

Jennifer Pulley

Thanks! Hey, Terry!

Dr. Terry Kucera

Hey, Jennifer!. SOHO or Solar Heliospheric Observatory has a dozen different instruments that keep the Sun under observation 24 hours a day without interference from the Earth’s atmosphere.

These instruments record the activity of the solar corona, the photosphere, and even study the sun’s deep interior. SOHO has a telescope on board that takes pictures of the Sun in ultraviolet light. Also, SOHO can give us a 2-3 day early warning of coming solar storms that can affect the earth’s magnetic field.

Jennifer Pulley

That’s really cool. Thanks, Terry! What’s next Sten?

Dr. Sten Odenwald

The second satellite, The ACE or Advanced Composition Explorer operates

…like an ocean buoy that measures density, temperature, magnetism, and speed of the solar wind that passes by. If a solar storm is headed our way, ACE will detect it and give us a 30-45 minute warning that a storm is about to hit Earth.

Jennifer Pulley

Cool! So how do NASA researchers analyze and interpret the data?

Dr. Sten Odenwald

One way we can analyze and interpret the data is by graphing.

This graph shows the speed of the solar wind changing as it blows by the ACE satellite. The title of this graph is Solar Wind Speed. The horizontal axis or x-axis represents the number of days in September of 2000 and the vertical axis or y-axis represents speed in km/s.

Jennifer Pulley

Okay Sten, It looks like the speed of the solar wind ranged from 350 km/s to 800 km/s during the month of September.

Dr. Sten Odenwald

You’re right Jennifer. On September 18th, the solar wind reached speeds of 800 km/s or about 1.7 million miles per hr. But most of the solar wind averaged around 450 km/s. From the analysis of this graph, we can determine how long it took the solar wind to reach Earth’s atmosphere.

Jennifer Pulley

That’s amazing Sten….. Besides SOHO and ACE,…

you mentioned a third satellite… IMAGE? Is that the one you’re working on?

Dr. Sten Odenwald

That’s right Jennifer.

IMAGE which means Imager for Magnetosphere-to-Aurora Global Exploration satellite is a satellite that orbits Earth and it measures the locations and changes in the invisible clouds of particles that surround the Earth in space. You, probably, already know one of these cloud systems, the van Allen belts.

Astronauts and satellites avoid these belts because of their radiation hazard. There is also a separate collection of particles called the Ring Current which appears and disappears whenever the Earth gets whacked by a solar storm. Another one of these clouds called the plasmasphere is actually part of our own atmosphere. It extends over 10,000 miles above the earth. The IMAGE satellite lets us watch these different families of clouds change. IMAGE helps us understand how solar storms can cause problems for our technology in space, and the health of astronauts working there too. More importantly, it helps scientists improve our ability to forecast space weather.

Jennifer Pulley

Wow. I realized the sun was critical to sustain life here on Earth, …

… but I never realized the devastating effects the Sun can have on us.

Dr. Sten Odenwald

It’s amazing Jennifer… solar storms have caused billions of dollars worth of satellite damage in the last 20 years.

They have caused blackouts,

and will always be a hazard for astronauts working in space.

Satellites like SOHO, ACE, and IMAGE and their replacements will be our only means of keeping track of when the next storm hits Earth’s magnetic field.

If students would like to learn more about how the sun works and about solar storms, they can visit the Sun Earth Day web site which was developed by the Sun Earth Connection Education Forum, in collaboration with the NASA Office of Space Science.

Jennifer Pulley

Thank you so much, Dr. Odenwald. You know, Dan, has been working on some web sites about the Sun.

Let’s go see what he’s up to!

Dan Geroe

Welcome to my domain. We've got a cool activity on our NASA CONNECT Web site to help you explore problems related to solar weather. It's a PBL, or Problem Based Learning activity,

Here's the problem you and your classmates will try to solve. You are the secretary of your club and you have used a pager and cell phone to let your committee know about the time for your next meeting. When no one responded, you made several calls the next day and found that no one got your messages. You want to find out what went wrong.

Go to Dan's Domain on the NASA CONNECT Web site to find out more about how to solve the problem.

You'll also find a link to NASA Goddard’s Sun — Earth Connection Education Forum.

Here you’ll find a lot of great resources to help you in your exploration. One of the resources is a guide to space weather. In it you’ll see images and information about such things as Sunspots, Solar Cycle, Solar Flares, Auroras and more.

Check out the link to the Eclipse Archive. It gives detailed information for all eclipses of the Sun and Moon from 2001 through 2005. And teachers — there's an excellent educator’s guide that you can download from the Web site.

This guide is designed to provide educators with a quick reference to materials and resources that are useful for understanding Sun and Earth connections.

The Web-based activity I've just talked about could be used for collaborating with other NASA CONNECT classrooms around the world.

ePALS.com has a Web site that provides a meeting place and collaborative tools that over 4 million teachers and students can use to connect with other classrooms and work on projects like this together.

All you have to do is have your teacher create a profile for your class. Make sure to include the keywords "NASA CONNECT" in your profile.

By using ePALS' search tool, your teacher can easily find other NASA CONNECT classrooms. You'll also find free teacher-monitored email for students as well as collaborative tools like moderated discussion boards and chat rooms.

That’s it for my Domain. Now, back to the Maryland Science Center!


Jennifer Pulley

Okay. Let’s review. We’ve learned about the basic parts of the sun. We’ve learned how research scientists study the sun with different types of light radiation.

Dan Geroe

We’ve also learned that satellites provide us with this information!

Jennifer Pulley

Right! But what if we could "see" the events leading up to solar storms? Dr. Michelle Larson from the University of California at Berkeley has the scoop!

Cue Card Questions

1.What is the goal of the HESSI satellite?

2. When do solar flares occur on the Sun?

3. How do solar flares have a direct effect on the Earth’s atmosphere?

Dr. Michelle Larson

Hi, I’m Michelle Larson and I’m an astrophysicist. An Astrophysicist is a researcher who studies physics in space! I’m here at Vandenburg Air Force Base in California with the HESSI satellite. Let’s take a look!

HESSI, or, High Energy Solar Spectroscopic Imager is designed to learn more about the basic physical processes that occur in solar flares.

Teams of astrophysicists and engineers work together to decide what kinds of observations HESSI will make and what kinds of scientific instrumentation will be required.

The HESSI teams will achieve their goal by taking pictures of solar flares in the x-ray and gamma ray radiation range.


What is a Solar Flare?

Dr. Michelle Larson

Well, remember when Eric told you that solar flares are the biggest explosions in the solar system?

A solar flare occurs when magnetic energy that builds up in the solar atmosphere is suddenly released.

Charged particles, such as electrons, protons, and heavier ions… travel away from the Sun along magnetic field lines. Others move towards the surface of the Sun and emit x-ray and gamma ray radiation as they slow down.

Flares produce all forms of electromagnetic radiation, from radio waves and visible light to x-rays and gamma rays.


Why study solar flares?

Dr. Michelle Larson

The biggest flares are as powerful as billions of hydrogen bombs exploding at the same time! We still don’t know what triggers them or how they release so much energy in such a short time …

…but solar flares have a direct effect on the Earth’s upper atmosphere.

For instance, long distance radio communications can be disrupted by the effect of flares on the Earth’s ionosphere that is a part of the Earth’s atmosphere.

In addition, energetic particles accelerated in solar flares that escape into interplanetary space are dangerous to astronauts outside the protection of the earth’s atmosphere and magnetic field and, also, to electronic instruments in space.


Where do solar flares occur?

Dr. Michelle Larson

Solar Flares occur in the solar atmosphere.

Inside a flare, the temperature is roughly 10 times hotter than the corona and can be as high as 100 million degrees Celsius.

The frequency of solar flares varies with the eleven-year solar cycle. At a solar minimum, very few flares occur.

As the Sun approaches the maximum part of its cycle, they occur more and more frequently. Let me show you on this graph…

Let’s look at the graph of actual solar flare data from 1990 to 2001. The title of this graph is # Solar Flares vs. Years. The horizontal axis or x-axis represents Years and the vertical axis or y-axis represents the Total Number of Flares Recorded. From the graph, we can see that we have a solar maximum in 1990 and one in 2001. We have a solar minimum at some point between 1995-1996.

This graph shows us that the Sun does have a solar cycle, which is about 11 years. From this graph we can predict when the next solar maximum and minimum will occur.


How do you study solar flares?

Dr. Michelle Larson

Well, it’s actually very difficult to study the high energy x-rays and gamma rays emitted during solar flares.

To solve this problem HESSI uses a very unique method. HESSI will obtain pictures of solar flares within the x-ray and gamma ray range by using pairs of metal grids to cast shadows onto detectors. Each grid is a bit like a fine screen, but with lines running in only one direction, like jail bars. The solid slats block radiation and the open slits allow radiation to pass through.

As the satellite rotates, at about 15 times per minute, the grids will allow high energy x-rays and gamma rays from different parts of the Sun to sometimes pass though and sometimes not, depending on how the slats are oriented. The HESSI detectors will measure the energies of the x-rays and gamma rays that get through and will record how things change as the satellite, and therefore the grids, rotate. This is enough information to figure out where the radiation came from on the Sun.

This information will be transmitted to the ground, where HESSI scientists will use it in their computers to make pictures of flares in X-rays and gamma rays.

It is like putting together the pieces of a puzzle to figure out what the picture is.

The special way HESSI will measure high energy radiation from the Sun, combined with the way scientists will analyze the data, will allow us to study the Sun in a way never before attempted.


Why will HESSI observe Solar Flares in the X-ray and gamma ray range?




Dr. Michelle Larson

We know that light emitted in the x-ray and gamma range show different events than that in the visible light range.

High energy X-rays and gamma rays carry the most direct information available about the energetic particle activity on the sun that occurs in solar flares.

With the help of HESSI we will be able to anticipate solar flares and HESSI will aid in understanding energetic events throughout the Universe.

Jennifer Pulley

Thanks Michelle! Say, how would you like to plot out the cycles of solar flares? Students at Hardy Middle School in Washington DC will show you how!… Check out my nose!




We’re from Hardy Middle School…


… here in Georgetown, Washington DC.


NASA CONNECT has asked us to show you this Hands On Activity!


It’s called — X-ray Candles: Solar Flares on Your Birthday.


Here are the main objectives!


· you’ll discover the solar cycle through an investigation of solar x-rays flares.

· you’ll record the total number of flares in your birth month over an eleven year period.

· you’ll compute the percentage of M — class flares that occur.

· you’ll graph your findings to help you identify the long term pattern of flare activity on

the Sun.

· and you’ll incorporate problem solving strategies in a real-life application.

The list of materials you’ll need for this activity can be downloaded from the NASA Connect Web Site.

The class will be divided into groups according to their birth month. Teachers will provide each group with solar flare data for the corresponding birth month and each student with a calculator, graph paper, and student data charts.


"Good morning class. Today your job is to plot and analyze solar flare data from a satellite and to determine the solar cycle of the Sun."


First, add the total number of flares that occurred in your birth month for each year. Record that number in the last column of each row of the solar flare data sheets.

Second, add all the numbers in the last column of the solar flare data sheets to determine the total number of flares in your birth month for each year. Record that number for each year in the box at the bottom of each page of the solar flare data sheets

Next, add the total number of M class flares in your birth month for each year. Record the total number of M class flares for each year in the box at the bottom middle of each page of the solar flare data sheets.

"What did you get for your birth month?"


Groups will need to collaborate with each other to get information on the total number of flares and M class flares for all months in each year. Record the data on the student data chart.

Record the total number of flares and M class flares for each year on the student chart.

From this data, compute the percentage of M class flares for each year by using the equation:

"M-class flares divided by total number of flares multiplied by 100."

Students will then plot the percentage of M class flares versus year.


"Okay, why is it important for researchers and scientists to know when solar maximums and solar minimums will occur?"


So they know when solar storms will hit the earth.


Anybody else? Alison?


So they can warn us if the electricity will go out in our homes.


Special thanks to the AIAA National Capital Section and the AIAA Mentors from the

University of Maryland who helped on this show!!

AIAA Mentor

Thanks! We had a great experience!

And, we encourage teachers to visit our web site to learn more about the AIAA Mentorship program in your area!

Jennifer Pulley

Well, that wraps up another episode of NASA CONNECT!

Dan Geroe

We’d like to thank everyone who helped make this program possible!

Got a comment, question or suggestion? Email them to


Or pick up a pen and mail them to


NASA's Center for Distance Learning

NASA Langley Research Center

Mail Stop 400

Hampton, VA 23681

Teachers! If you would like a video tape of this program and the accompanying lesson guide, check out the NASA CONNECT web site.

From our site, you can link to the NASA Educator Resource

Center Network. These centers provide educators free access to NASA products, like NASA CONNECT!

Or, from our site, you can link to CORE, the NASA Central Operation of Resources for Educators.

To view this and past NASA CONNECT shows on your computer, visit NASA QUEST @ quest.nasa.gov

So, until next time, stay connected to math,




See you then!



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