Individual Lab Exercise #3.C: Solar Flares and Coronal Mass Ejections (This is a brand new lab I have devised, so please let me know if there are any serious glitches.) Instructions: Place your answers in the appropriate location on this Word Document. When you are finished with the assignment, copy and paste this document (with your answers, obviously) into the appropriate individual Lab Journal on BBLearn (i.e., Stellar Zoo #). In light of the recent and highly publicized solar activity, I have developed these exercises to allow you to investigate Solar Flares and Coronal Mass Ejections. These activities will make use of several resources provided by NASA and affiliated researchers. In working through this exercise, the following “Frequently Asked Questions” page from NASA may prove useful to you: http://www.nasa.gov/mission_pages/sunearth/spaceweather/index.html (If the destructive/disruptive nature of solar flares/ CMEs coupled with the absurd public fears of the world ending in 2012 concerns you, I suggest you view NASA’s explanation of why the Sun most certainly will not destroy Earth: http://www.nasa.gov/topics/earth/features/2012.html The following video is useful as well: http://www.nasa.gov/topics/earth/features/2012-superFlares.html ) Part 1 - Solar Observatories: Before we look at the actual solar activity, you will need to further investigate the tools used to observe solar phenomena. Watch the “Heliophysics 101” video located at the NASA Heliophysics Division’s website: http://www.nasa.gov/mission_pages/sunearth/overview/index.html Question: Briefly describe the advantages given by the 4 main NASA spacecraft used for solar observation (SDO, SOHO, & STEREO A/B): Soho is providing scientists with a comprehensive study of the Sun, the nuclear powerhouse in the center of our solar system. Its twelve experiments, developed by scientists from Europe and the United States, are investigating the Sun from its core outwards - from the very inner workings of the star, to the solar wind which blows through the solar system. It will provide a better understanding of the Sun and its importance to life on Earth. Soho has lunched to study Sun.  it is currently the main source of near-real time solar data for space weather prediction. Along with the GGS Wind and Advanced Composition Explorer (ACE), SOHO is one of three spacecraft currently in the vicinity of theEarth-SunL1 point, a point of gravitational balance located approximately 0.99 astronomical unit (AU)s from the Sun and 0.01 AU from the Earth. In addition to its scientific contributions, SOHO is distinguished by being the first three-axis-stabilized spacecraft to use its reaction wheels as a kind of virtual gyroscope; the technique was adopted after an on-board emergency in 1998 that nearly resulted in the loss of the spacecraft. Question: Why is it important to view the sun at many different wavelengths? Question: What types of light are best at detecting solar flares? Wha.

1. Individual Lab Exercise #3.C: Solar Flares and Coronal Mass
Ejections
(This is a brand new lab I have devised, so please let me know
if there are any serious glitches.)
Instructions: Place your answers in the appropriate location on
this Word Document. When you are finished with the
assignment, copy and paste this document (with your answers,
obviously) into the appropriate individual Lab Journal on
BBLearn (i.e., Stellar Zoo #).
In light of the recent and highly publicized solar activity, I have
developed these exercises to allow you to investigate Solar
Flares and Coronal Mass Ejections. These activities will make
use of several resources provided by NASA and affiliated
researchers.
In working through this exercise, the following “Frequently
Asked Questions” page from NASA may prove useful to you:
http://www.nasa.gov/mission_pages/sunearth/spaceweather/inde
x.html
(If the destructive/disruptive nature of solar flares/ CMEs
coupled with the absurd public fears of the world ending in
2012 concerns you, I suggest you view NASA’s explanation of
why the Sun most certainly will not destroy Earth:
http://www.nasa.gov/topics/earth/features/2012.html The
following video is useful as well:
http://www.nasa.gov/topics/earth/features/2012-
superFlares.html )
Part 1 - Solar Observatories:
Before we look at the actual solar activity, you will need
to further investigate the tools used to observe solar
phenomena. Watch the “Heliophysics 101” video located at the
NASA Heliophysics Division’s website:
http://www.nasa.gov/mission_pages/sunearth/overview/index.ht

2. ml
Question: Briefly describe the advantages given by the 4 main
NASA spacecraft used for solar observation (SDO, SOHO, &
STEREO A/B):
Soho is providing scientists with a comprehensive study of the
Sun, the nuclear powerhouse in the center of our solar system.
Its twelve experiments, developed by scientists from Europe and
the United States, are investigating the Sun from its core
outwards - from the very inner workings of the star, to the solar
wind which blows through the solar system. It will provide a
better understanding of the Sun and its importance to life on
Earth.
Soho has lunched to study Sun. it is currently the main source
of near-real time solar data for space weather prediction. Along
with the GGS Wind and Advanced Composition
Explorer (ACE), SOHO is one of three spacecraft currently in
the vicinity of theEarth-SunL1 point, a point of gravitational
balance located approximately 0.99 astronomical unit
(AU)s from the Sun and 0.01 AU from the Earth. In addition to
its scientific contributions, SOHO is distinguished by being the
first three-axis-stabilized spacecraft to use its reaction
wheels as a kind of virtual gyroscope; the technique was
adopted after an on-board emergency in 1998 that nearly
resulted in the loss of the spacecraft.
Question: Why is it important to view the sun at many different
wavelengths?
Question: What types of light are best at detecting solar flares?
What is the physical source of this form of light?
Question: How do these spacecraft observe Coronal Mass
Ejections?
Part 2 – Solar Flares & Coronal Mass Ejections

3. For this portion of the lab, you will examine real data from
SDO, SOHO, & STEREO in your hunt for solar flares. There is
a convenient tool funded by the ESA & NASA that you will be
using for these purposes: http://helioviewer.org/
Helioviewer allows you to look at still images of the sun
from numerous spacecraft and at numerous wavelengths of
light. You will use this tool to look at specific events in many
wavelengths of light and you will create a video of the recent
solar activity.
· Open up the Helioviewer and familiarize yourself with the
interface.
· The left-most menu allows you to select the date, time, and
step increment for your observations. The “Images” section
below the “Time” control allows you to select which spacecraft,
instrument, detector, and observation wavelength
(measurement) to use. By selecting the “[Add]” option, you can
build a composite image made of many different views of the
sun at that point in time.
· The center panel is the data visualizer and its operation is
quite intuitive. If you have ever used Google Maps or similar
programs, this interface should be quite familiar to you. You
can navigate by using the zoom slider on the upper-left as well
as dragging the sun around when you are zoomed in close.
Notice the options in the upper-right corner (Link, Movie,
Screenshot, Settings.) You will be using these to make videos
of a powerful solar flares & CMEs.
Flare Exercise:
Find the X5.4 flare of March 6, 2012. That is, navigate to
March 6, 2012 with the “Time” control panel. You will need to
set the “Images” panel to use the data from the Solar Dynamics
Observatory (SDO), using the AIA instrument at a measurement
value of 171.
View the video of this flare at the following link:
http://www.nasa.gov/multimedia/videogallery/index.html?collec
tion_id=15504&media_id=135006681

4. Step through time in 1-hour increments until you are at
about 02:00 UTC. You will notice the X5.4 flare in the upper-
left side of the sun from this view. Change the time-step to 1
minute increments and compose a movie of this event.
(Basically you are replicating the video from the above link.)
In order to compose the movie, select “Movie” in the upper-
right corner of the data viewer. Choose “Full Viewport” then
select “6 hours” to begin the video rendering process. The
Helioviewer will alert you with a pop-up notifier when the
movie is ready to view.
After previewing your movie for any glitches, you will need to
select the “Get a link to the movie” button on the bottom of the
viewport. Copy and paste that link into this worksheet below.
Your link to March 6, 2012 X5.4 movie:
CME Exercise:
Now that you have some experience with Helioviewer, I want
you to find a recent Coronal Mass Ejection (CME) and compile
a movie of that event. For this movie I want the SDO imagery
taken with AIA at a measurement of 304 (mostly like the last
movie,) but I also want you to include the STEREO-B imagery
of the solar corona. That is to say, click “[Add]” and select
“STEREO-B” “SECCHI” ”COR2” ”white-light.”
You can pick any recent CME you wish, but make sure there is
both SDO & STEREO-B imagery for the same event. The time
& date stamp for each layer should be a bright green color, not
red or orange.
The following link will prove useful in your efforts:
http://helios.gsfc.nasa.gov/cme.html
Use the NASA Heliophysics website and/or Wikipedia to find
when a CME occurred and make a movie of the event. These
events are reasonably quick, so make sure your time-step value
is set to 1 minute and you compile the movie over at least a 6
hour period. Follow the same procedures to make the movie
and paste the movie’s link in the appropriate spot below. Here

5. is a link to an example I found:
http://helioviewer.org/?movieId=3CY55 . Notice the activity on
the sun itself preceding the CME seen by STEREO-B.
Time & Date of your selected CME:
Link to your CME event movie:
Describe what occurs during this event in terms of what
each of these spacecraft observed:
Current Solar Activity Exercise:
Next, I want you to look at the most recent series of solar flares
and CMEs. Using the composite few from the previous
exercise, make another movie of the SDO/STEREO-B imagery
that spans most of a month. Following the same procedures as
before, choose a 28 day period within the last two months to
observe. Here’s a link to a similar video I compiled as an
example: http://helioviewer.org/?movieId=RCY55
Paste the link to your movie in the appropriate spot below and
give a description of what is happening over this extended time
period.
Link to recent CME activity:
Description:
The previous movie shows a good picture of the recent CME
activity, but now I want you to make a final video for this
laboratory that focuses on flares. Using the same time range
and time-step, make a movie of the recent flare activity as seen
from SDO’s AIA instrument with a measurement value of 171.
Paste the link below and give a description of what has
happened over that 28 day period.
Link to recent flare activity movie:
Description:
Individual Lab Exercise #3.A: Hertzsprung-Russell Diagrams
(Adapted from Univ. Nebraska – Lincoln)

6. Instructions: Place your answers in the appropriate location on
this Word Document. When you are finished with the
assignment, copy and paste this document (with your answers,
obviously) into the appropriate individual Lab Journal on
BBLearn (i.e., Stellar Zoo Lab #).
For this lab you will be using WorldWide Telescope &
Wikipedia to find the spectral characteristics of select stars and
explore Hertzsprung-Russell Diagrams using the HR Diagram
Explorer from UNL:
http://astro.unl.edu/naap/hr/animations/hr.html
In WWT, you will need to use the “Search” feature in order to
locate these stars. By using the “Finder Scope” in WWT (that
is, right-click or shift+left-click on the object) you will see a
variety of physical properties associated with that object. By
clicking on “Research” then navigating to “Information” “Look
up on Wikipedia” you will see a list of the spectral information
of that star. (This is one reasonably rare case where Wikipedia’s
information is correct; many dedicated astronomers have
contributed to vetting this class of information.)
Note: You may find it best to unselect the “View from this
location” option under the “View” menu since this turns off the
horizon which may obscure your view. This lab can be run
under whatever date/time you wish since our only concern is the
spectral characteristics.
Exercise 1: Fill out the table below to summarize the
relationship between spectral type, temperature, and color for
stars. Note that the surface temperature of the stars in the table
increases.
Star
Surface Temperature (K)
Spectral Type

7. Color
Constellation
Betelguese
M2
Arcturus
4,300
G2
Yellow
N/A
Procyon A
F5
Yellow-White
Sirius A
A1
White
Rigel A
11,000
Delta Orionis
O9

8. HR Diagram Explorer
Open the HR Diagram Explorer at
http://astro.unl.edu/naap/hr/animations/hr.html
· Begin by familiarizing yourself with the capabilities of the
Hertzsprung-Russell Diagram Explorer through
experimentation.
· An actual HR Diagram is provided in the upper right panel
with an active location indicated by a red x. This active
location can be dragged around the diagram. The options panel
allows you to control the variables plotted on the x-axis:
(temperature, BV, or spectral type) and those plotted on the y-
axis (luminosity or absolute magnitude). One can also show the
main sequence, luminosity classes, isoradius lines, or the
instability strip. The Plotted Stars panel allows you to add
various groups of stars to the diagram.
· The Cursor Properties panel has sliders for the temperature
and luminosity of the active location on the HR Diagram. These
can control the values of the active location or move in response
to the active location begin dragged. The temperature and
luminosity (in solar units) are used to solve for the radius of a
star at the active location.
· The Size Comparison panel in the upper left illustrates the
star corresponding to the active location on the HR Diagram.
Note that the size of the sun remains constant.
· Check “show luminosity classes”. This green region (dwarfs
V) is known as the main sequence and contains all stars that are
fusing hydrogen into helium as their primary energy source.
Over 90% of all stars fall in this region on the HR diagram.
Move the active cursor up and down the main sequence and
explore the different values of stellar radius.

9. Question: Describe the sizes of stars along the main sequence.
What are stars like near the top of the main sequence, the
middle, and the bottom?
Exercise 2:Finding the brightest, nearest stars
Make sure you have all four of the “show” buttons selected (e.g.
“show main sequence,” “show luminosity classes”) and click on
each of the options in the “Plotted Stars” portion of the
simulator. Notice where the nearest stars and the brightest stars
fall on the HR diagram.
Select “the overlap” in the HR Diagram Explorer to see
only the brightest, nearest stars on the HR Diagram. I want you
to use WWT and the stellar information on Wikipedia to
identify four of the five brightest, nearest stars.
Tips on finding these stars: Explore the sky view with WWT to
identify the brightest stars in the sky. By selecting each of
those stars with the “Finder Scope” you can see the apparent
magnitude of the object to verify that it is indeed a bright star;
that is to say, the magnitude should be close to or less than
zero. As we’ve seen from the text, the apparent magnitude is
really a confluence of stellar luminosity and distance so this
serves as a good indicator in your search for the bright, near
stars. You can click on each of the plotted stars in the HR
Diagram Explorer to see what luminosity & temperature you are
looking for or refer to the table below. Do note that the values
you find in the Wikipedia entries may not exactly match what is
listed on the “Cursor Properties” but they should be close.
For example, I selected the star on the HR Diagram with a

10. Temperature of 7600 K and Luminosity of 10. By searching the
sky in WWT I narrowed down the possibilities by investigating
the brightest stars first. After a few tries, I found that the star
Altair has a luminosity of 10.6 and a temperature of 6,900K to
8,500K. In addition, the distance to Altair is 16.73 light-years.
All of this together tells me that Altair is indeed one of the
brightest, closest stars.
Complete this exercise for the four remaining stars in the table
below:
Temperature (K)
Luminosity (in solar units)
Star Name
Distance from Earth (lyr)
7600
10
Altair
16.73
9600
24
6400
7
5800
1.6
5100
0.55