Solar Storms and You!
Activity 5: Solar Activity and Coronal Mass Ejections
The Sun constantly emits matter into space in the form of a more or less
steady solar wind. From time to time the Sun also ejects individual clouds
of gas in an event called a Coronal Mass Ejection, or CME. CMEs can cause
storms in the environment of the Earth that can have harmful impacts on
humans working in space, on communication satellites, and many other aspects
of our technology dependent society. For this reason, scientists look for
many clues as to how and when the next one may happen to provide us with
Students will construct a graph to compare the sunspot cycle with Coronal
Mass Ejections (CMEs).
Teacher notes on the graphing calculator, Part 1
and Part 2.
Students will use the graphing calculator to create the graphs
for the sunspots and the CMEs. Students will graph the sunspots and the
CMEs on graph paper. Note: Using different colors to depict each
graph will allow for ease when comparing the two graphs.
Students compare the two graphs. Location of the maximums, the
minimums, and the time frames are the key components. Have the students
determine if there is a correlation.
Discuss the possible relationships that the students locate. Among
the things to consider are: - How well does the CME activity follow the
sunspot cycle?- Do the maximums and the minimums happen at about the same
Solar Wind: A flow of matter from the surface of the Sun which passes
through interplanetary space.
CMEs: Coronal Mass Ejections are sudden ejections of matter
from the Sun's outer layers.
Cme activity should follow rather closely the sunspot cycle, but the correlation
in exact counts may not be precise. This is probably because CMEs happen
in layers of the Sun that are much higher above the solar surface than
the sunspots. The CME curve seems to have a longer, flatter minimum than
the sunspot curve and its center is offset from the sunspot minimum by
2-3 years earlier. CME activity may decline to a minimum faster than sunspots
after sunspot maximum.
Related Web Resources
Loa Solar Observatory has an archive of MPEG movies of major CMEs during
the last 10 years. At the end of the main page is a link to their deep archive
of solar storms dating from 1980.
Geophysical Data Center has an archive of sunspot data ( daily, monthly,
yearly averages) that goes all the way back to the 1600s. Click on 'Sunspot Numbers' in their list and the FTP session will start.
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This activity was developed by the NASA, IMAGE/POETRY
Teacher and Student Consortium.
For more information, and a list of other resources, visit