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 Native American Connections
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Click here to view the 9M movie!
The idea is to allow students to experience the dynamics of the sun and its interaction with the magnetosphere of Earth.
By experiencing a mime and space science demonstration, these difficult and abstract concepts become more accessible.
Students feel on more solid ground when they eventually pick up a book or read an article about plasma, solar wind, and magnetospheres.
Personification is a literary figure of speech in which a non-human object or creature is referred to as if it were a person. If we were to say something like, the sun smiled down upon us, is a personification. The sun is not really a person smiling, yet the image conveys a sense of how we relate to the sun. The very names of the planets are personifications. When we speak of Mother Earth, we are referring to the ancient idea of Earth as a mother to all living things, personified by the ancient Greeks as the goddess Gaia. When we are trying to understand the dynamics of the streaming of plasma from the sun throughout the solar system as it comes up against the planetary magnetospheres, it is helpful to personify these invisible fields, forces, and particles in order to aid our understanding.
Solar wind
is hot plasma, ionized matter moving at half a million to a million miles per hour. The highly energetic particles carry electrical charges and the structure
of the Sun's magnetic field lines. They move out in massive waves, a constantly spiralling 3-dimensional streaming out from the dense atmosphere of the
Sun. No matter how dispersed the plasma particles become, they remain "hot" because they move so fast - and so do not dissipate their heat.
Within this oceanic environment of the solar wind are the planets, some of which have strong magnetic fields that interact strongly with the solar wind. It is as if the magnetospheres protect the planets from the full brunt of the solar wind. We are only beginning to fully understand.
Form two teams in an open area:
The Sun, with its solar wind, and Earth with its magnetosphere.
Like a sprinkler in the back yard streaming forth water, the Sun with its gravitational rotation sends highly energetic charged particles throughout the Solar System.
Place 1, 2, or 3 people in the center, arms waving energetically. Place enough other people (7-10) to surround them, backs to the center in a circle around the center of the Sun. These participants represent plasma which is hot and dense in the atmosphere of the Sun. Let the outer ring of people also undulate their arms to show the magnetic field lines. Then let them each walk out from the Sun to show how particles can remain hot with high energy, but also become less dense as they more further from the Sun.
Meanwhile, let one person be Earth. Arrange 7 or 8 others in an outer circle, each person facing toward the Sun. Let these participants undulate
their arms to represent Earth's magnetic field and its magnetosphere. Let the "solar wind" move out in waves a million mph in slow motion. The students do not collide, but stream around Earth.
Let one person stand near Earth's magnetosphere, facing the Sun with arms outstretched, representing the collisionless bow shock. The
magnetosphere acts as a shield, creating a bow shock that compresses the sunside of Earth's magnetic field, causing the solar wind to flow
around the Earth, streaming Earth's field off into a tail. Some plasma particles from the solar wind reconnect with open field lines from Earth's
polar regions. As the solar wind plasma enters the magnetosphere it creates a light show display which we demonstrate as the dance of the auroras.
CRITICAL THINKING ABOUT
Kinesthetic Variation: Explorer I
Some plasma particles from the solar wind get trapped by Earth's magnetic field lines, creating doughnut-like regions of denser energetic
particles.Have students create a performance of this great moment in science history!
When Sputnik, the first spacecraft, was launched in 1957, the American space program was anxious to respond in kindÐ not just to launch a
satellite, but also to learn something new! Fortunately, Dr. William Pickering, then Director of the Jet Propulsion Laboratory, knew just who
to call to devise an experiment with the right stuff! He called upon Dr. James Van Allen, who had been exploring the upper atmosphere with rockoons,
rocket-launched balloons that could obtain data about radiation levels. Van Allen and his team placed a Geiger counter and an altimeter
on Explorer I to take radiation readings at different altitudes. During the flight, radiation levels seemed to increase and then suddenly drop to zero
and then again, seemed to increase and then suddenly drop to zero. What was going on? How would you have approached this problem?
On later Explorer missions, the scientists recalibrated the Geiger counters and discovered that the regions appearing as zero really went off
the scale. These high-radiation regions were mapped and are now known as the Van Allen radiation belts.
Hints on re-creating this scene: Students may play the parts not only of the people involved, but the technologies as well! Invite one student to
represent Sputnik beaming its radio signal around the Earth for all to receive on their ham radios. Let the countdown begin for the launch
of Explorer I! Invent a way to show the Geiger counter on board, perhaps using wild motions of the arms to represent the readings. Or have the
students clatter drumsticks on a hard surface to represent the geiger readings.Describe how the Geiger counter became more active as
Explorer I went higherÐ and have the student move the arms more rapidly. Then describe how some regions showed readings of zeroÐ and have the student
drop the arms motionlessly. Then show how the scientists re-calibrated the Geiger counter for later flights and how they created a more accurate
picture. Or show Van Allen and his team scratching their heads at mission control, trying to interperet the incoming readings. What might have been
other explanations for the initial results?
A Mythical Magnetic Moment
Aurora is the Roman goddess of the dawn. The story goes that a young man named Tithonus fell in love with her glorious raiment, the incredible
display of colors as morning would break, and in the night sky, her diaphanous appearance like a kaleidoscopic dream of ribbons of color. She, too, fell
in love with him. Ah, but she would live eternally, and he was but a mortal. Flushed with new love, Aurora asked Jupiter to grant Tithonus immortality, which
was done! At first, they were happy because they would be able to be together in love forever. But then to their regret, they realized that Aurora forgot
to ask for Jupiter to grant Tithonus eternal youth! As Aurora rose each morning to bright the light of the dawn to all creature on Earth, Tithonus aged
more and more as the years rolled by, still in love, but no longer the handsome youth who stood on the hillside in the deep night awaiting the arrival of
the beautiful dawn, Aurora!
Mime learning Variation: Magnetic Fields
Can you feel the effect of invisible radiant energy? Try this! Rub the palms of your hands together vigorously. Now place your palms near your face. Do you feel the radiant heat created by the friction? Great!
Now let's mime a magnetic field. Stand face-to-face with a partner. Place your hands straight out in front of you touching your partner's outstretched
hands. Push gently, then gently resist your partner's pushing of your hands. Gradually add strength, so that the back & forth, push & resist motion becomes
a bit more active. Then stop, move your hands an inch apart from each other- leaving a cushion of air between your hands and your partner's hands. Now
resume the back & forth push & resist motion without touching hands. Use increasing strength. If you imagine your hands as magnets repelling like
against like, the strength of the repelling action is like the magnetic field, exerting its unseen influence.
The Solar Wind Meets the Magnetosphere
MIME & SPACE SCIENCE EXPLORATION
Form two teams in an open area:
Team 2: Forming Earth, with its Magnetosphere
Let the "solar wind" move out in waves a million mph in slow motion. The students do not collide, but stream around Earth.The magnetosphere
acts as a shield, creating a bow shock that compresses the sunside of Earth's magnetic field, causing the solar wind to flow around the Earth,
streaming Earth's field off into a tail. The person playing the bow shock, directs this activity like a traffic cop. After passing the Earth,
some plasma particles from the solar wind reconnect with open field lines from EarthÕs polar regions. As this happens, this interaction creates
a light show display which we demonstrate as the dance of the auroras.
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