Transcript Unit 2 The Earth in Space - lperleyPhysicalGeography110

History of Beliefs
Geocentricity Theory
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Greek Ptolemy’s theory
The idea that the sun revolves around the
earth
Supported by the Church
Heliocentric Theory
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Earth revolves around the sun
Considered by the Christian Church as heresy
until Copernicus (1543) and Galilei (1632)
The Sun
The Center of Our Solar System
The Sun – Our Star Attraction
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(18 minutes)
Quiz at the end
Facts about the Sun
Age
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4.6 billion years old (half way through its life)
Distance from Earth
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149,597,900 km
Mass
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332,900 times Earth’s mass
Volume
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1.3 million times the Earth’s volume
Rotation Rate
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25.38 Earth days (equator)
Diameter
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109 time Earth’s diameter
1,391,000 km
Characteristics of the Sun
The sun is about 72% hydrogen, 22% helium
and 1% of other elements
At the core: Nuclear fusion
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Every second, 600 million tons of hydrogen fuse
to form 596 million tons of helium.
The remaining 4 million tons of hydrogen is converted
into energy that makes the Sun shine
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It takes a million years for this energy to reach the
Sun’s surface. Much of the energy is converted
from harmful gamma and x-rays in the form of
visible light.
This light energy takes 8 minutes to reach
the Earth
Anatomy of the Sun
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Core
Radiative Zone
Convection
Zone
Photosphere
Sunspot
Solar
Prominence
Chromosphere
Corona
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Core
The Sun’s nuclear furnace, where fusion reactions initially
combine hydrogen atoms to produce helium yielding
energy in the process
Temperatures reach 15 million oC and pressure is
enormous
Radiative Zone (moving gases)
Energy moves through a surrounding envelope of gas
Convection Zone
Big bubbles of hot gas transport energy to the surface
Photosphere
The Sun’s visible surface. Due to its high temperature, it
glows yellow.
It is made up of churning gases, it is not a solid surface
5. Sunspot (Active Region)
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A magnetic storm on the Sun’s surface that is generally cooler then
the photosphere around them
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Sunspots always occur in pairs
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Sunspots are intense magnetic fields that break the Sun’s surface
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These field lines break through one sunspot and reenter into another
These are 1000 to 20,000 km in diameter
These frequently generate solar flares
Solar Flare:
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A solar flare is an eruption of hot gases from the inner atmosphere
of the Sun’s surface.
It travels very quickly and last for only minutes.
“Fountains of hot gases” that travel outward from the chromosphere
through the corona
The charged particles from a solar flare affect us in two main ways:
They produce the beautiful auroras (the particles / energy interact
with the Earth’s poles), and they cause problems in communication
systems.
Note: The number of sunspots and solar flares peaks every 11 years when
the magnetic field of Sun flips over.
http://www.space.com/27834-monstersunspot-solar-flares-video.html
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Solar Prominence
A solar prominence is a burst of a huge sheet of gases,
also from the inner atmosphere. It is much larger than a
flare and may last for days or even weeks.
The huge sheet of gases lines itself up along the
magnetic field created between the pairs of sunspots
They can go as far as 50,000 km or more above the
Sun’s surface
Chromosphere
The inner atmosphere
Corona
The Sun’s outer atmosphere where gas temperatures
reach over 1 million oC
Sun’s Rotation
The Sun rotates on an axis
The Sun’s interior rotates at a different rate then
than outer surface
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The interior (the core and radiative zone) are believed to
rotate as a solid
The outer parts (the convective zone and out) are believed
to rotate at different rates that vary with latitude
The result: The outer surface does not rotate at the same
rate. As latitude increases, the rate of rotation slows
down.
At the equator (middle) – rotation rate is 28 (25) days
At the poles – rotation rate is 37 (36) days
Sunspots are a great way to see the movement
Activity 1 and 2
Complete each of the following activities
on the Solar graph paper provided.
Answer questions in complete sentences
at the bottom of the solar graph paper (3).
Activity 1: Plotting Sunspots
Plotting Sunspots Activity
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Using the Solar Graph paper, plot the points
given in the table. Each represent a sunspot
location
Label each plot with the corresponding
number
Question 1:
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Where do sunspots appear to be occurring on
the Sun? Give the value in degrees.
Activity 2: Tracking an Active Region
Tracking a Sunspot
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Using the Solar Graph paper, plot the points given in
the table.
Label each plot with the corresponding date
Question 2:
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What pattern does the movement of AR7220 have?
How far does it move each day?
Question 3:
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The first day AR7216 was seen it was located at
N13E75. After 12 days, where would you expect it
be?
Activity 3: Historical Data Sunspot Location
Using the data provided, graph the
number of sunspots from the 1700’s to
2001. Look for patterns – does it match
the research?
Hand-in
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Properly labeled graph.
Questions answered in full sentences.
Sunspots of Our Sun
Approximately 11 year cycle
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Discovered in 1843 by Samuel Heinrich Schwabe
Solar maximum
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peak in number of sunspots
Often high number of solar flares during this
time
Solar minimum
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low number of sunspots
Fate of Our Sun
https://www.windows.ucar.edu/tour/link=/s
un/fate.html
Eventually our Sun will …
Deplete its supply of hydrogen
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the core will shrink
temperatures will climb
And it will begin to burn helium which in turn will form heavier elements
Form a red giant as the surface will puff up like a balloon, growing
cooler, redder
It will eat up all of the inner planets
Not be able to release enough energy to form new elements and
hence, fusion will stop
Shed its outer layers, surrounding itself with a planetary nebula (a
colorful gas bubble)
This nebula will dissipate distributing various gases – carbon,
oxygen, etc.. - throughout the solar system
Only have a collapsed core = 60 percent of the Sun’s mass (the size
of earth)
Be a dead remnant, White dwarf, that will eventually cool and fade
from sight
Note that not all stars die this way
The fate of a star is dependent on its mass
Average stars end as the Sun will
Larger stars will end in a massive
explosion – a supernova
Massive stars (10 times that of the Sun),
simply collapse into their inner core
forming a black hole
Crab Nebula
5 minutes
Videos\The_Formation_and_Destruction_
of_Stars.asf