Transcript Focusing on Visible Light

Energy
the
from
Sun
Living With a Star
Sun Facts
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The Sun is rather ordinary when it comes
to stars.
In fact, there are 100 billion stars in our
galaxy that are similar to the Sun.
What makes our star unique is that it is
ours—responsible for light, heat, and life
as we know it.
Learning Objectives
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Appreciate the scale of the Sun-Earth
The sun emits a range of energies that make
up the Electromagnetic EM spectrum.
The range extends beyond the visible
spectrum in both directions, beyond the red
and beyond the violet.
ROYGBIV
The sun is a star that sheds a continuous flow
of particles (solar wind) and electromagnetic
radiation.
and there’s more folks…
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The Sun’s outer atmosphere is called the
corona.
During solar storms, huge bursts of
electromagnetic energy are emitted by
solar flares
Flares are sometimes accompanied by
Coronal Mass Ejections (CMES) –
eruptions of particles in the corona
EM energies travel at the speed of light
Some solar output is harmful
Scale Model Demonstration
What does the Earth get
from the Sun that is
essential to keep us alive?
What evidence do you have that
there is energy reaching you
from the Sun?
Focusing on Visible Light
Photons
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Light is made up of bundles of energy
called photons which travel through
space.
Each color of light is made of different
photon energies.
The energy level carried by violet light is
about twice as much as red light.
ROYGBIV
Colors in Visible Light
Electromagneti
c energies
travel at the
speed of light
Electromagnetic
Low Energy
Spectrum
Very High Energy
Particles from the Sun
Particles travel
at less than the
speed of light
Slower
particles
Faster
Particles
Photosphere
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The visible portion of the Sun.
Random Walk
For the Sun, a photon is generated at
the center and makes its way to the
surface. It may take up to a thousand
years to get to the surface, and the
form of the energy may change from Xray to visible wavelengths. When the
photon leaves the Sun, it takes eight
minutes to get to us at the speed of
light.
The 8-minute
travel time to
Earth by
sunlight hides
a thousandyear journey
that actually
began in the
core.
Sir Fredrick William Herschel
In 1800, Sir Fredrick William
Herschel split up sunlight
using a glass prism instead
of a diffraction grating.
Herschel's experiment was
important not only because
it led to the discovery of
infrared light, but also
because it was the first time
that someone showed that
there were forms of light
that we cannot see with our
eyes.
Infrared Video Clips
Colors in Visible Light
ROYGBIV
Electromagnetic
Electromagneti
c energies
travel at the
speed of light
Spectrum
Infrared
Low Energy
Very High Energy
Particles from the Sun
Particles travel
at less than the
speed of light
Slower
particles
Faster
Particles
CD ROM
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Play movie Infrared and Its Uses
Ultraviolet or UV
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Right of the violet end of the spectrum.
Invisible to humans
Bees can see it
Judging by where ultraviolet energy is
located on this spectrum, do you think it
has more or less energy than visible light?
What have you heard about UV?
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Cause sunburn
Damage our eyes
Sunscreen and
sunglasses block it
Colors in Visible Light
Electromagneti
c energies
travel at the
speed of light
ROYGBIV
Electromagnetic
Radio Waves Microwaves
Infrared
Low Energy
Spectrum
Ultraviolet
Very High Energy
Particles from the Sun
Particles travel
at less than the
speed of light
Slower
particles
Faster
Particles
CD ROM
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Looking at various wave lengths that make
up the electromagnetic spectrum.
Solar Wind Particle
Coronal Mass Ejections CME
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Occasionally, a part of the Sun’s upper
atmosphere (corona) erupts in a giant
gust of solar storm particles called a
Coronal Mass Ejection or CME
Some CMEs are ejected outward from the
Sun in the direction of Earth.
CMEs often accompany solar flares.
Colors in Visible Light
Electromagneti
c energies
travel at the
speed of light
ROYGBIV
Electromagnetic
Radio Waves Microwaves
Infrared
Low Energy
Spectrum
Ultraviolet
X-Rays
Gamma Rays
Very High Energy
Particles from the Sun
Particles travel
at less than the
speed of light
Slower
particles
Faster
Particles
The Culprit in the Mystery
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Will CME, EM and solar wind knowledge
help decide if the Sun caused the January
disruptions in Earth?
What happened to the Sun at 3:10 on
01/25?
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If the solar flare affected Earth in eight
minutes, why did many of the mysterious
events happen two days later, on 01/27?
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Do CMEs travel at the speed of light?
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Is the Sun always sending out both EM
energy and solar wind?
How fast does EM energy travel?
How fast does solar wind travel?
What happened on the Sun on 01/25?
What happened on the Earth around
3:18?
What happened on the Earth two days
later?
What do you think caused the events on
01/27?
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Knowing what you know now, do you
think the solar flare and CME caused the
mysterious events in Activity 1?