Transcript star - Teacher Pages

Lesson 1: The Sun
What would
Earth be
like without
the sun?
How would
you
describe
the sun?
What is the
Sun?
The sun is a star.
A star is an
object that
produces its own
energy, including
heat and light.
The planets
and the other
objects in the
solar system
are not stars
because they
do not
produce their
own light.
The sun is the largest object in the
solar system.
If the sun where a hollow ball, more than a million Earths
could fit inside it.
However, if comparing the sun to
other stars, it is just average in size.
The only reason the sun looks so
much larger than the other stars
that can be seen in the night sky, is
because it is so much closer to
Earth.
The sun is 92,960,000 miles away from
Earth. To make this distance easier,
astronomers call this distance one
astronomical unit.
The next closest star to our
solar system is 271,931 AUs
away!
What is the sun?
The sun is a star (an
object that
produces is own
energy).
The sun is the largest object in our
solar system.
How does the sun produce its own
energy?
Albert Einstein discovered a
relationship between mass and energy.
He showed this
relationship in a
now-famous
equation: E = MC2
E = MC2
E -> energy
M -> mass
C -> the speed of light (671 million mph)
This formula shows that just a little
bit of mass can be turned into a whole
lot of energy.
The sun is mostly made up of the gas
hydrogen.
Hydrogen has very little mass.
However, inside the Sun, the
hydrogen particles smash together.
This
smashing
together is
called
fusion.
A little bit of mass is lost when H particles
combine to make helium. According to Einstein’s
equation, that little bit of mass is changed into
energy. We see this energy as light and heat.
So the
process of
fusion is how
the sun
produces
energy.
How does the sun
produce energy?
The sun’s hydrogen atoms
smash together and form
helium (fusion) and some
energy is released.
What are the parts of the sun?
Scientists have
divided the sun
in layers.
Most of the
energy the sun
produces is
formed in its
core. At its
core, the
temperature is
around 10-20
million degrees
Celsius.
The radiation
layer moves the
energy out
from the core
in every
direction. It
can take
millions of
years for
energy to move
out of this
layer because
it’s moving
randomly
around.
In the
convection
layer, gases
move in
circles,
similar to air
currents.
Energy moves
out of the
layer in about
a week.
The
photosphere
is the visible
surface of
the Sun. It
is not solid,
but a layer of
gases.
It’s obviously cooler here—only
10,346 degrees.
The chromosphere, or inner layer of
the sun’s atmosphere, can be seen like a
red circle around the sun.
The corona is the outermost layer of
the sun’s atmosphere. It takes on
different shapes depending on the
changes in temperature.
Solar Flares
Solar flares are bursts of heat and
energy that stretch out from the
corona into space.
Sometimes, this
energy can disrupts
satellites, interfere
with TV, radio and cell
phone communication
on Earth.
Solar flares are the causes of
displays of different colored lights in
the upper atmosphere.
These lights
are called
aurora
borealis, or
northern
lights.
They are most often seen in Alaska,
Canada, and the north US.
They’re
only seen
in the
southern
US if the
sun
releases
large
amounts
of energy.
Solar flares are also associated with sun
spots. Sun spots, or dark spots on the
sun, are sections of the sun that have a
lower temperature than the surrounding
areas.
Lesson Review
1. What is the largest object in our
solar system?
The sun
2. The sun is a star. What is a star?
An object that produces
its own energy (light and
heat).
3. Why are the planets NOT stars?
Planets do not produce their own
energy (light and heat)
4. What two gases make up most of
the Sun’s matter?
Hydrogen and helium
5. How does the Sun produce energy?
Hydrogen particles smash together
and create helium and energy, which
is called fusion.
6. How would the Earth be affected
if the sun stopped producing energy?
Without the sun’s energy,
everything alive on Earth would
die.
7. All of the following are part of our
solar system EXCEPT
A. the sun.
B. Earth.
D. The stars
C. the Moon.
The only star in our
D. the stars.
solar system is the sun!